How can I know when a thick simple syrup is done cooking? When making a thick simple syrup (1 part water, 1 part white sugar), how can I know when I've cooked the sugar for long enough?  Is it possible to overcook this?

You aren't actually trying to cook anything. When you heat a solution, it makes dissolving a solid in to that solution much easier. So you can dissolve more sugar in to hot water than cold water. With a 1:1 ratio, you wouldn't be able to get all the sugar in to solution with cold water. So, you heat the water to allow more sugar to become part of the solution. So the answer is, as soon as there is no visible sugar in the water, you are done.

If you were to cook it for longer, you would reduce the syrup, increasing the concentration of sugar in the solution. You'd have to reduce it an awful lot before you burnt this. However, if you reduce it too much, then the liquid will become solid when it is cooled. Both of those would probably qualify as "over cooked".

Here's a nice science description of sugar solubility. Interestingly, they say that sugar has such high solubility in water that you can get 1800g in to 1L. Using this volume to weight conversion site, that's approximately 7.5 cups of sugar in 1L of water. 1L = 4.2 cups, so you can get ~1.8 Cups of sugar in to 1 cup of water (under ideal circumstances). So, if you are actually interested in cooking your water off to get a more sugary syrup, you can't reduce the water to less than 1 / 1.8 = or 55% of the original volume. However, if you do want a ratio higher that 1:1, then I would suggest introducing the appropriate amount of sugar in the first place and stopping when the sugar is dissolved rather than using less sugar and cooking the liquid down, as the first approach is much more precise.

(for purposes of this answer, I have ignored the possibility of super saturating the syrup, as that would be essentially useless for cooking....although it would be funny)


Food safe airbrushing I've been hand painting colored cocoa butter into chocolates molds for a while now, but I'd like to try airbrushing the molds instead, since I've seen some impressive results. I can't figure out a food safe way to do this, though.

The most obvious way seems to be buying an oil-free compressor and a fancy air brush. That seems to be $200 and up, though, which is more than I'm interested in spending.

Another common approach is to use something like the Badget 250 and a can of compressed air. The Badget 250 is only around $15, making it a lot more viable. Apparently, even Norman Love does this:

"Another technique [Norman Love] showed us was airbrushing color into his molds. He uses "Mini Spray Gun Set 250-4" made by Badger company. It's the cheapest air brush out there. He hooked up to a can of air instead of a compressor. This cheap air brush lets you spray thick liquids (chocolate) and has easy clean up and no cloging. He mentioned plumpers use this type of brush... Oh, the can of air gets very cold while using and can freeze up. So he places it in a warm pot of h2o to prevent that from slowing him down. It also can be hooked up to a compressor, of course."

http://www.cheftalk.com/forum/thread/8093/chocolate-demo-by-norman-love

That's great, except that all the compressed air I can find contains a propellant which is highly unlikely to be food safe. Can you buy food safe compressed air? If not, how do you do food-safe airbrushing without spending hundreds of dollars?

Thanks!

Both CO2 and N2O should be sold as "food safe". N2O is commonly used for whipped cream. I can't vouch for mechanical compatibility, though.


Why are there no nutrition facts on this US bottle of vinegar? I recently noticed that a bottle of Heinz white vinegar that I purchased a while back has no nutrition facts label on it despite the fact that it's intended to be used with food. Is there a reason why the label wasn't required?

It may depend on the size of the label on the bottle - there are exceptions for small label area. Looking at a gallon bottle (different brand) that has the label, the numbers are all 0 anyway, which offers another option. If you happened to purchase it from a restaurant supply, that offers yet another exception.

  (j) The following foods are exempt from this section or are subject to special labeling requirements:

  (4) Foods that contain insignificant amounts of all of the nutrients and food components required to be included in the declaration of nutrition information under paragraph (c) of this section, Provided, That the food bears no nutrition claims or other nutrition information in any context on the label or in labeling or advertising. Claims or other nutrition information subject the food to the provisions of this section. An insignificant amount of a nutrient or food component shall be that amount that allows a declaration of zero in nutrition labeling, except that for total carbohydrate, dietary fiber, and protein, it shall be an amount that allows a declaration of “less than 1 gram.” Examples of foods that are exempt under this paragraph include coffee beans (whole or ground), tea leaves, plain unsweetened instant coffee and tea, condiment-type dehydrated vegetables, flavor extracts, and food colors.

  (13)(i) Foods in small packages that have a total surface area available to bear labeling of less than 12 square inches, Provided, That the labels for these foods bear no nutrition claims or other nutrition information in any context on the label or in labeling or advertising. Claims or other nutrition information subject the food to the provisions of this section. Foods in packages subject to requirements of paragraphs (j)(13)(ii)(A)(1) and (2) of this section do not require the information in paragraphs (d)(9) and (f)(5) related to the footnote, however the abbreviated footnote statement “% DV = % Daily Value” may be used.

Legalese from : http://www.ecfr.gov/cgi-bin/retrieveECFR?gp=1&SID=4bf49f997b04dcacdfbd637db9aa5839&ty=HTML&h=L&mc=true&n=pt21.2.101&r=PART#se21.2.101_19


My bone broth dehydrated in slow cooker overnight My bone broth dehydrated overnight to the point where the meat and veggies were brown and dry on top. I've added water back in, but was wondering if it is any good.  Perhaps I'll have a batch that tastes different.

The temperature will have been high enough to be safe, so don't worry.

What you'll get is a darker, quite tasty stock. It's not suitable for everything (it's likely to be cloudy as well as dark) but can be very good. When I first got my new slow cooker it tended to do this, because it runs a little hotter than my old one. Running it on low instead of high (starting with boiling liquid) solved that.

You can also use the concentrated stock you've made, just remember to use much less than you would of normal stock.


Why exactly do leafy vegetables turn to mush when frozen uncoooked? I've heard 2 explanations: because of enzymes that get destroyed when cooking (which is chemical) and because plant cells expand when the water inside freezes, and then the cells burst (which is mechanical). Which one is it really? Or both?

On that note, why does cooking (blanching/sautéing) preserve their texture after freezing and thawing? The fact that it does seems to be an argument against the 'burst cells' explanation, since the cells are still full of water after freezing.

In freezing, it is mostly the bursting of the cell walls as the ice crystals expand.

Much like a water balloon holds its shape when it is intact, but becomes flaccid when punctured, so to the cell walls comprising the vegetable.

See related, for why a similar thing happens when you cook spinach:
Why does spinach lose its texture when cooked?

Cooked vegetables are already soft and their metaphorical balloons partially deflated.  It is not going to get a lot worse for the freezing.  The par cooking is mostly disable enzymes which would change the color of the vegetable to dull olive drab, or negatively affect the flavor.

See: Why blanche vegetables before freezing?


What is the pho "original" chile? Every Vietnamese restaurant I've eaten in (in the US) uses jalapeno peppers in their pho.  I assume that's an American adaptation to the dish.  Is that correct?  If so, what kind of peppers are used in Vietnam?

I'd go with Bird's Eyes, or as they're sometimes called, 'finger' chillies.
I'd define it as skinny, thin skin, lots of seeds - finger tend to be larger, green; bird's eye smaller, red.
The trouble with chillies is that they can all look a bit alike & trying to buy one very specific type is really not easy. Is it a jalapeño, is it a fresno or a serrano… what's the real difference? Can you tell just by looking, or even tasting?
You can easily tell the difference between a scotch bonnet & a jalapeño, of course, not only do they look completely different, they taste & smell completely different, but a lot of the others come in much finer distinctions.
Finger chillies & bird's eyes are close to being the same thing. They're not identical, but to the consumer it's really tough to tell them apart. Supermarkets tend to call the larger ones finger & the smaller ones bird's eye - they taste the same. See https://www.sainsburysmagazine.co.uk/lifestyle/food/a-guide-to-chillies for how the supermarkets very, very broadly differentiate.
BTW, I can tell the difference between a jalapeño & a fresno… but not if the ones the supermarket is selling this week look like something half-way between the two.
Late thought - cayenne looks like a 'finger' variety too; All I can think is they call them finger if they're green & cayenne if they're red. They never really tell you exactly what they are.


Presto multi cooker sous vide- clarification? I read Marc-André LaFortune's post about using the Presto multi cooker as a secondary sous vide machine.

I'm interested in doing this but it would appear to me that the machine is not accurate enough without modification to hold the pot to +/- .7 F.
Do you do this by monitoring temperature with a thermometer and switching it on and off, or with a PID controller like others have used?

The standard hack is to use a PID controller.  IF you google, you will find many articles detailing exactly how, such as this detailed one from Over Engineered.

There are now also a couple of vendors of moderately low cost circulators intended specifically for this application such as Sansair that you insert into a pot or cooler.  They are new to the market, so there are some early adopter issues being reported, but the idea is quite elegant.


What are the benefits of Ceylon cinnamon over Chinese cinnamon? I have read that Ceylon cinnamon is sweeter. It is also 3X the price. Is it really worth it?

They both have a similar flavour but Ceylon cinnamon but your right that it can be slightly sweeter. It also has a different texture (more crumbly) which you may prefer for use in recipes. Chinese cinnamon does have a stronger flavour but some people actually prefer this so it's really just a matter of taste so it's difficult to say whether it's 'worth it'. It can be difficult to get hold of hence it being so expensive. If you're a huge cinnamon fan perhaps purchase yourself a small amount so that you can compare?


Achieving perfection via manual drip-brew coffee method Every time I make coffee it seems to taste different, and I've found there is a lot more room for error with the manual drip-brew method than using a Moka coffee maker or an automatic drip-brewer.

There are too many variables to list, but I'll try:

Type/color/brand of filter
Amount of coffee
Wetting the filter
Wetting the grounds
Amount of time between wetting the grounds and pouring the rest of the water
Plastic / ceramic / glass cone
Coarseness of the grounds
Rate of water flow
Temperature of water
Height from which to pour water
Trickling water or constant pour
Clockwise / counterclockwise / or straight-on pouring
Whether to fill it up to the brim and let it seep down or be patient and pour a little at a time
And many more.

But what are the most important factors (either from this list or anything I might have missed) that I need to do every time to ensure that the cup is a most excellent brew?  How do those factors actually affect the brew and why?

Please include only factors specific to, or of particular import to this method of coffee brewing.

Background
The manual drip technique (AKA "filtercone brewing") and an automatic drip-brewer are very similar; both involve pouring water through a conical filter into a vessel.  The difference is that an automatic drip-brewer maintains consistent and hopefully ideal conditions, so when you drip-brew manually, you are essentially trying to recreate the environment inside an automatic drip-brewer.
Much of the following is derived from sweetmarias.com - my constant source for coffee information.
Customizing your coffee
The most important variables in terms of how much they affect the end result also happen to be easily isolated variables that you can control simply with tools.  They are:

Temperature of the water
The best temperature is when the water is just coming to a boil, around 200° F or 93.3° C.  An automatic drip-brewer will generally maintain a temperature of between 195° F and 205° F.
Water that is too cold won't extract enough of the oils and will give you flat, flavorless coffee.  Water that is too hot will extract a lot of the proteins and give you very bitter coffee.
This is simple to control for; just use a thermometer, or learn how to recognize when the water is just about to boil.

Coarseness of the coffee
The grind (obviously, a fresh grind especially) is important here, as it is with any distillation method. What you need to remember is that you are matching the temperature and pressure of extraction.
For high pressure extraction (espresso), uniformly fine grind is preferred to ensure that the water does not shoot past the puck too quickly. For lower pressure methods (i.e. manual drip), you want a medium grind to ensure that the water passes easily but not too quickly.
Again, this is simple to control for; just use a good, reliable coffee grinder.

Ratio of water to coffee grounds
This is mainly a matter of personal preference.  Figure out what you like, but ensure that this is the final variable you are isolating. Use a measuring spoon, start at 8 grams (about 1 rounded tablespoon) per 5 oz water, and start experimenting from there.

Improving your consistency
Once you've dealt with the obvious factors above, proper technique becomes essential to improving on the consistency of your brewing process.  You'll want to watch out for:

Steady heat during the pour
Depending on the material your filter cone is made of, it may take a while to heat up, which means that initially the water will lose heat to the cone and become too cold before it passes through the coffee.
You can compensate for this by pre-heating the cone.  Use hot water for this; don't use the microwave, especially if it's a plastic cone.
Ceramic cones are more heat-stable than plastic, but will take longer to heat up, so it's more important to pre-heat them.  You probably don't need this stability because the water shouldn't be in the cone for too long - unless you're brewing a full pot. Most pour-overs should really only be for about 20 ounces of coffee.

Pour Time
The best automatic coffee makers have a sprinkle head and pour out over a deliberately extended period of time, as opposed to shoving the coffee through in a rush. This is because you are trying to extract flavor as thoroughly as possible, and quick is not thorough.
Maintain a slow, steady pour.  Trickling is less effective since it will cause an uneven leaching from the grinds, so be wary of this.  Submerging is even less effective because you will lose heat from your water as it sits there.  This is probably the most important part of a good brewing technique.
It should take 4-5 minutes, pouring evenly over all the grinds, to extract a full 10 cup pot. Hopefully your arm is strong or you're only doing 1 cup.
More practically, you will want to refer to this chart on specific infusion times: For example, for a #4 filter, and 20 ounces of coffee, you will want to spend 2 minutes and 30 seconds on the infusion (they recommend 32g or ~4 rounded Tbsp of coffee).

Wetting the filter
This applies when your filter falls down (as wetting it keeps it up) - not a big problem with conical filters. That said, in some cases rinsing off your filter is preferred in the event that your filter gives an off-flavor. I personally have never encountered this with unbleached filters.

Wetting the grounds
There are two schools of thought on this.  Some say to do it, others say not to do it because it locks up the oils or stales the coffee when done too far in advance.
In the case of a straight pour over filter, non-vacuum, sweetmarias.com recommends "blooming the coffee 15-30 seconds" by sprinkling with a pre-pour. (I assume that's what 'wetting the grounds' meant. In my experience, premature moisture is less of a problem for beans with more sugar, i.e. lighter roasts.)
As for time between wetting filter/grounds, you should minimize wetness of coffee in the interest of freshness by thermal conservation, or refrain from either step.

Height of pour
This matters mainly because you don't want to splash water or grinds everywhere, but more importantly you don't want the water to lose heat on its way down by pouring too far.

Rotation of pour
Pick one, do it evenly across all grinds.  The important thing here is consistency.

Miscellaneous tips and tricks

According to sweetmarias on the quantity of coffee:

Simply using more coffee grinds cannot fix other brew problems: If you use 20 grams coffee and 350 ML of water and 4 minutes steep time to achieve 20% extraction (it should), using 40 grams coffee with a contact time of 1 minute to compensate will not result in a better cup.

Consider removing the drip before the final drops go through.  According to Voilley et al., Eval., 287:

Perceived coffee bitterness is lower when coffee is brewed hot than when cooler water is used. This is hypothesized to be due to the heightened aromatics released in hot coffee, which counteract the bitterness.

So watch out for those last few drops, because they will tend to have lost some heat and will thus leach more solids with fewer aromatics, resulting in more bitterness.

Now go enjoy some hand cranked coffee consistently.


Why might I have trouble making butter from Crème Fraîche? I tried making cultured butter today from a supermarket variety crème fraîche. For some reason the butter hasn't split from the whey although I've "churned" it with the hand mixer for 20 minutes or more.

This recipe for cultured butter suggests that about 2 to 5 minutes is needed with a food processor, and my previous experience with the hand mixer is about 10 minutes for sweet butter.

I checked the ingredients list of the crème fraîche and I don't see anything unusual: cream* and an unspecified culture. That's it. No artificial thickeners for example.

What could be the problem?

Update:

I'll just note one avenue I've already explored: temperature. I've tried varying the temperature during churning from just above freezing to around room temperature.

* The cream is "högpastöriserad" which is Swedish for a pasteurization process where the cream is held at 80°C for 5 seconds. I'm not sure this term translates directly to a common English term.

If you were using supermarket cream, the reason would be very clear: it is not only pasteurized, but also homogenized. This means that it has been mechanically emulsified to prevent the butter from separating.

I don't know if the cream for creme fraiche is homogenized too before creme fraiche is made, but with your result, I'd suspect homogenization too. It won't show up on the label as an ingredient, as it is done by forcing the cream through microfilters.


How can I adjust oven temperature correctly I recently bought an oven but it was just yesterday that I saw that the knob for the temperature does not indicate any temperature. Only hi and lo. How can I adjust the temperature correctly?

It sounds like you need to buy an oven thermometer.  Put it on the same rack you'll be using for baking, and it will tell you what "hi," "lo," and in between (if available) settings really mean.


How do I make Udon noodles fat? When I get Udon at a restaurant, they're these massively thick noodles. When I cook them they look like linguine. What am I doing wrong?

Many of the dried noodles that are marketed as "udon"—at least in my experience in the USA—are actually mislabeled, thinner noodles like Hiyamugi or even Sōmen.  I would suggest buying the semi-dried variety that are usually packaged in vacuum sealed plastic.  This variety is shelf stable, but it can often be found in the refrigerated section of Asian mega-marts.  The noodles will already be almost full size before cooking.


Homemade butter not softening properly Recently made butter in my stand mixer.  Squeezed it dry and rinsed it before kneading in sea salt.  However, when left out the butter is not softening as store bought butter would to make it spreadable.

So I'm wondering which part of the process might affect this.  Did I over-drain it? Or is the salt keeping it solid at warmer temps? Or something else?

Over churning is my guess. You want to churn the butter until it starts to setup but no more.


How do I make the beef in my beef stroganoff more tender? Tonight I prepared some beef stroganoff with a recipe from allrecipes.com as a rough guide.  It came out really well, except that the meat was very tough.

I bought the meat pre-cut as "stew meat," as recommended by the guy at the meat counter at the supermarket, and thus not specifically chuck roast. I bought it last weekend, expecting to prepare it that day, but plans changed, so I didn't prepare it until now.

I covered the meat (~1 lbs, cut up) with some white flour, then browned it until it was maybe 70% brown (a little red still visible), prepared the rest of the sauce, then let the sauce and meat simmer for an hour.

Did I brown the meat too fast?  Did letting it sit in the fridge for a couple days make it more tough?

Supermarket 'stew beef' is notoriously unreliable.  Its often just scraps of beef that the butcher or market can't sell otherwise.  My stews were hit and miss for years while I tried to tweak cooking time and such. But then one day I watched a movie on rouxbe.com (paywall, sorry) and they talked about not using 'stew beef' - its often too lean and doesn't have the 'stuff' to produce tender, but juicy bits.  They strongly recommended cutting up your own from a chuck....and they were so, so, so right.

In short, cutting up your own chuck is by far the better route - if you're looking for 'stew beef'.


What is the best recipe for Chocolate Mousse: with butter or cream? All the recipes I've got for chocolate mousse say among the ingredients: heavy cream or heavy whipping cream. I would like to know the difference if it exists.

I'm from Venezuela; what other ingredient can replace these for this recipe or any recipe that  needs this cream?

The percentage of milk-fat determines the name.  It is different from region to region.

In the US, heavy whipping Cream is above %36 fat.  You can see this chart for the naming convention and fat content.  For a chocolate mousse you're generally looking for cream with fat contents between %30 and %40.  Otherwise you can get a phase-inversion in your mousse emulsion (it break or collapses).

There are Chocolate mousse recipes using butter instead of cream.  It makes for a slightly different tasting chocolate mousse, but hey, it's chocolate mousse.
You may be able to cheat using an emulsifier such as soy lecithin to keep the emulsion stable.  Gelatin does thicken things, but you're likely to lose the air bubbles in the mousse and get a denser mix.


Ice Cream Bar Wrapping Machine Suggestions? I have been making some ice bars recently, and was wondering what the most cost-effective way would be to package them.

I am not talking about Haagen-Daaz level of production capacity but more like a mom-and-pop store kind of capacity, which will be done by hand ;)

Is there an affordable machine/tool that can zip/seal my ice cream bars? I thought about one of those vacuum sealers but I don't think they won't look that good.

I did some research on the types of wrappers and noticed that there is a smooth-end version (picture 1) and a sawtooth-end version (picture 2). I personally prefer the smooth-end version because it looks more elegant.

Or, if such machines are too expensive, are there any other good options that can yield the same results? Maybe custom ordering a pre-sealed package with one end open and has an adhesive on it so I can just slip the bar in and simply zip it that way?

Again, it doesn't have to be of high-capacity. I'd really appreciate your input on this! ;)

Just use lightweight "zip-loc" style bags. They are available in all sorts of sizes. It only has to be freezer safe, not 100% vacuum packed

Many packaging printers can "screen print" plastic bags


How can I "cheat" on dough maturation? I found a good balance between leavening and maturation while using my favourite flour, my oven and my sourdough starter, the only problem is that the whole process, from mixing the ingredients and producing a baked dough/focaccia requires more than 24h, about 1 day and a half.

I know at least 2 ways of "cheating" on the leavening, with some fructose/easy to digest sugar or a warmer temperature, but maturation is harder, it looks like there is no real answer or shortcut to that.

My main problem here is to shorten the amount of time required while getting the same or a really similar result.

The easiest method, and most common in a commercial setting, would be to add a small amount of yeast in addition to the sourdough starter. You will probably have to reformulate a bit, as the dough will mature faster leaving the starter less time to develop flavor. This is usually overcome by also increasing the proportion of starter (and adjusting the final dough's hydration based on the hydration of your starter).

For instance, if your original recipe included 30% starter (in baker's math), the faster version might have 40% starter and .5% yeast. If you use a liquid starter, you may then cut the water by 5% or so, and if you use a solid starter no further adjustment may be needed.


Yorkshire Puddings with Fish in Sauce What is the reason that Yorkshire Puddings are considered to only be served with roast beef / or perhaps as the batter for Toad-in-the-hole? (NB For non-UK residents, this is a baked dish consisting of sausages enrobed in Yorkshire Pudding batter.)
Background: I'm considering using a single large Yorkshire Pudding as the vessel to contain fish fillets in a creamy, buttery sauce.  Should I be dissuaded?  If so, for what reason(s)?
I await your answers with battered breath.

This has made me so hungry I came back down to write!
1:  Yes!  But I would not use roast drippings or suet as shortening for fear of overwhelming the fish with beef.  Anything else.  Duck fat would be lovely.  Lard or vegetable shortening or butter ok.  It might not be as stiff with butter.
2:  Have sauce added by diner on top right before eating or it will sog out the pudding.
3:  What deserves to be in with the fish?  Leek or carrot or parsley all very precious and would be visually spectacular.  But thinking @bob1 deconstructed fish and chips... what do you put on fish and chips?  Vinegar.  What wont soak the pudding but is vinegary and has some veg crunch.  A pickle!  A pickle spear in there with the fish would be perfect!
I was thinking also some of those crunchy premade onions like Frenchs makes for salad and hot dish but that is my belly talking.  You could have those on the side for the Americans to sprinkle on.


I followed the instructions, but my food still stuck to the wok I bought a very expensive Stainless Steel Baccarat Wok only last week. I followed instructions as told by the shop assistant (to wipe with a small amount of oil before I started to cook), but when I started to cook my wok had gone all brown like burnt and all my food was destroyed. Where have I gone wrong? Is there any way to keep this problem from happening again?

Stainless steel woks burn and stick very easily and are expensive and can't really be seasoned however they last forever. They are only used for foods that would attack a normal carbon steel wok and give the food a metallic taste, e.g. acidic foods.

Carbon steel woks are used by Chinese chefs and after proper seasoning they are like non stick but able to handle extremely high temperatures that Teflon can't.


Ideal coffee grind for a French Press? I recently picked up this Bodum "French Press" style coffee maker and so far, I'm really enjoying it for its simplicity. But I'm curious how I should be grinding my coffee.

When I bought it, I grabbed a bag of pre-ground coffee at the grocery store and this worked well. But recently, I bought a can of beans and put it thru the coffee grinder at the store and I may have chose too coarse a grind as I seem to be getting very weak cups of coffee now.

The manual said pick a "coarse" grind, so it turned the dial all the way to the left labeled "coarse". I'm thinking it should have been somewhere in the middle, like "Percolate".

Any advice on the optimal grind?

EDIT: Also, What ratio of Tbsp to oz of water? (or grams to ml, if you prefer metric.)

You do want a coarse grind for french press coffee. The key is letting the coffee steep for long enough to make a strong brew. I have good results with a 5 minute steep time. Be sure to use a timer, and compare different times to find the optimal brew. As a general rule, if you are at altitude, then you need to add time because boiling water is cooler. (Note that I am at 5000ft, so 5 minutes may be too long for you.)

Below is a picture of the coffee chunks in a coarse grind on top of a US 5 cent coin (21.21 mm in diameter).

The picture is from this article.

EDIT: The reason to use a coarse grind for a french press is that finer grinds will get stuck in the filter and/or push their way through. This has three potential problems: 1) it will be harder to press down the filter, possibly leading to spillage or breakage; 2) your coffee will have grinds in it; 3) the coffee may become bitter, as the finer grinds that passed through the filter remain in contact with the coffee for too long.


Preservation of baked goods with eggs When you bake (cookies etc) commercially with egg in your recipe, do you have to add any preservatives and if so, what?

The short answer: no. I cooked/baked commercially for years, and never used any sort of preservative/stabilizer. The cooking (baking) process is what stabilizes the product. The egg only goes 'bad' from a raw state, not cooked.


What's the Procedure for This Pie? What would be the procedure for this pie recipe from a 50 year-old cookbook?

1 1/2 c. mashed, cooked pumpkin
1/2 c. sugar
1/2 t. salt
1 1/4 t. cinnamon
1 t. ginger
1/2 t. nutmeg
1/2 t. cloves
3 slightly beaten eggs
1 1/4 c. milk
1 6oz can evaporated milk

This appears to be a standard custard-type pumpkin pie filling.

I would recommend, as the method:

Blind bake your crust approximately 10 minutes, using rice or pie weights to keep it from bubbling up.
Mix all of the filling ingredients together well.
Pour filling into the shell, and put in a 400 to 425 F for about 15 minutes, then lower the temperature to 350 F oven until done, about approximately 45-50 minutes.

You will know it is done when the filling is barely jiggly in the center, but set at the edges when you shake the pan, or when it registers 180 F on an instant-read thermometer.

If the crust starts to over brown, line the edges with aluminum foil or a pie protector.

There doesn't seem to be anything special about this recipe, so using a more modern recipe which is accompanied by more precise instructions should not sacrifice anything.


Is there a big difference between Yellow and Yukon Gold potatoes? After moving to Canada six months ago, I still haven't found Yukon Gold potatoes at the grocery stores. Instead I find Yellow potatoes and was curious as to whether or not they are considered to be the same or if they are completely different. I find that the texture is a little bit "harder" than the Yukon Gold potatoes but overall seem pretty similar. So, are Yellow potatoes the same as Yukon Gold and can they be used interchangeably?

They are often used interchangeably.  The truth is, yukon gold potatoes are a type of yellow potato.  They were developed in Canada.  You will definitely see them on store shelves here in Canada, but it can be seasonal, depending on your location.  I am in Winnipeg, and I find YG about six months of the year.


Why do some recipes call for sugar in a brine? In making a brine for my chicken, I came across a lot of recipes that call for sugar in the brine.  I understand the general idea behind brining, but don't understand what benefit the sugar provides.

In this answer, @papin links to a PDF that states the following (emphasis mine):

  The law of diffusion states that the salt and sugar will naturally flow from the area of greater concentration (the brine) to lesser concentration (the cells). There is also a greater concentration of water, so to speak, outside of the turkey than inside. Here, too, the water will naturally flow from the area of greater concentration (the brine) to lesser concentration (the cells). When water moves in this fashion, the process is called osmosis. Once inside the cells, the salt and, to a lesser extent, the sugar cause the cell proteins to unravel, or denature. As the individual proteins unravel, they become more likely to interact with one another. This interaction results in the formation of a sticky matrix that captures and holds moisture.

This makes it sound like sugar isn't really an important part of the osmosis process.

Is there a chemical/molecular reason to add the sugar, or is it just to add some flavor to the chicken breast?

The sugar is simply used for flavoring; the fact that it helps brine to a lesser extent is just an added bonus. The sugar also aids in browning via the Maillard reaction, though this can also result in burning in a high heat application.

I suggest brining two boneless skinless chicken breasts -- one in a salt-only brine and the other with the salt & sugar brine suggested by Cook's Illustrated. You should notice a difference in both flavor and appearance.


Lasagna in a sandwich maker I have some lasagna sheets that I would like to use, and our oven is rather unreliable.
Is it possible to prepare lasagna using only a sandwich maker? How could I go about doing this?

Why not; it can be a fun project.
It will need a lot of experimentation to make it work and it will not be a lasagna.
I'd completely cook the noodles, spread them on the sandwich maker, put a little bit of sauce and cheese in the middle, put another layer of noodles on top and press it down.
Depending on the size of your sandwich maker, you could even try multiple layers.
But it will be a kind of a pizza pocket.


Can we use white sugar, instead of brown sugar? I want to bake a cake but I don't have light brown sugar. Can I replace it with white sugar?

You can substitute white sugar for light brown sugar with no problem, in my experience.

Make sure you substitute by weight (grams/oz), and not by volume(cups/spoons). This is because brown sugar is slightly more dense, so you get more sugar in a cup than you do with light brown.


Can I replace baking soda with bread flour in a cake recipe that already has baking powder? Can I replace baking soda with bread flour in a cake recipe that already has baking powder?

Google was no help and I really need to make this birthday cake today. Buying baking soda just isn’t a good use of my time or money, and I don’t have the time anyways.

No. Not at all.

Baking soda is a leavening agent. Together with baking powder it gives your cake lift and airiness. Bread flour is just flour with a higher protein content. If anything, it will make your cake more dense (though not in such small quantities as you would have for baking soda). If a recipe calls for both baking soda and baking powder, the recipe is balanced to rely on both and omitting one will cause the recipe to fail (to some degree). How it will fail will depend on the recipe, which you haven't included.

If you already have baking powder, and don't have the time to find baking soda, I recommend that you instead find a different cake recipe that uses ingredients you already have at home - specifically one that does not require baking soda at all. Many cake recipes use only baking powder, so this should not be overly difficult.

You may be able to replace the baking soda with baking powder at a powder to soda ratio of something between 2-1 and 4-1 depending on who you ask (e.g. two teaspoons of baking powder for one teaspoon of baking soda). Depending on the type of cake this may create off flavors in your final product. This and other possible substitutions for baking soda in cakes are discussed on this site in the related question: Replacements for baking soda in a cake?

Note, while these options are available to you, I still recommend finding a different recipe, particularly if you're not set on this specific one you're already using.

Also, since you mention bread flour, I hope you're not using bread flour for your cake instead of all purpose flour or cake flour. These three flours are quite different and will cause different outcomes if you use one when the recipe calls for another.


How to cut beef tenderloin into Filet Mignon I bought a chunk of tenderloin and made several Filet Mignon out of it. I had a hard time cutting the filet into parallel shape with relatively smooth surface, like those we found in fine restaurant.

Because the tenderloin is just so tender and soft, the meat deformed as I applied the knife pressure, and even further as I cut through it.

Are there some techniques, or specific tools to cut steak out of tenderloin or tender piece of meant in general?

You should apply as little knife pressure as possible in order to keep the meat from moving as you slice. I can offer a few suggestions towards that end.

First you need to take the translucent white stuff off. That silverskin is much tougher than muscle and is probably making you use too much force as you cut through it. You also don't want it on your medallions, and it's much easier to take it off the whole tenderloin than the smaller portions.

Get your filet/boning knife and use its tip to get under one end of the silverskin, then lift up the flap and slice just under it, keeping your knife more or less flat and parallel to the table. The silverskin will tend to come off in strips -- it's made up of long lengthwise fibers. It is fairly strongly attached to the meat, so don't try to tear it off; use your knife to separate them.

At one end, it'll dive into/merge with the muscle -- you can see this in the large piece to the left in your photo. You'll probably end up with a little divot there; don't worry about it. The silverskin is waste -- it doesn't have any flavor and is impossible to chew -- so just toss it.

Next, you should use the sharpest, narrowest, and longest blade that you have (those are in order of importance, so if your chef's knife is way sharper than your slicer, use it). Your knife should be sharp enough that you don't really have to press down at all in order to cut the meat -- the weight of the blade should be providing enough force. The cuts you make will be the same as if you were slicing a roast. Use the longest possible stroke, smoothly moving the entire length of your blade through the cut. Generally, cutting by starting at the base of the blade and pulling towards you will allow the smoothest movement. If you don't make it all the way through in one stroke, restart the cut from the base of the blade as many times as you need to, rather than following with a push cut. (On the last little bit, to completely separate the portion, you can get away with it, though.)

Finally, there are two possibilities for the position of the tenderloin and your hands relative to each other. You should try them both to see which produces better results for you. You can portion either from the right or left end of the meat. (Assuming a right-handed knife wielder,) portioning from the left involves pressing your free hand against the cut face of the meat (where you separated the last medallion), supporting it. This is the way that sashimi is cut, and I find that it makes it easier to get evenly-thick and consistently-sized slices.

If that doesn't work for you, and you're still having trouble getting smooth faces to the medallions, you can cut from the right end, and use your free hand to squeeze or compress the meat (not too hard, though -- you don't want to damage it) to hold it still while you cut. In this case, grab the tenderloin just past where you're going to make the cut.

Ultimately, though, don't worry too much about the face of the cuts. Any unevenness less than about 3/16 of an inch won't even be noticeable once you've put a nice sear on it.


Thickening Eggs with Cornstarch Recently I stumbled across a recipe that uses corn starch to thicken scrambled eggs and was wondering if there was any advice on tweaking the recipe to try and keep the calorie count down.

3 Large eggs
1 1/2 tbs whole milk (I use 2%) - 1/2 tbsp per egg
1 3/4 tsp potato starch or cornstarch (I use cornstarch) -- 5/8 tsp per egg
3 tbs unsalted butter (I use half that) -- 1 tbs per egg

Not in the recipe but I also add 1/2 tps of garlic when making it

This ends up being a quick way to make some good eggs but want to make it more healthy if possible.

Let's look at the estimated calories in that recipe:

Eggs: 270
Milk: 12
Cornstarch: 15
Butter: 306

So, given that the single largest source of calories in that recipe is the butter -- more than the eggs! -- if you're looking to reduce calorie count cutting back on the butter to 1 Tbs is the way to go.   Of course, that will affect the flavor as well.  The cornstarch isn't significant in those quantities.

(calorie counts are via Google, but are consistent with what I've seen elsewhere)

My personal perspective is: if you're looking to reduce calories, simply eat less. Compromising flavor in order to save calories is pointless; just make delicious foods in very small quantities.


Cooking Chemistry: lemon juice/soymilk buttermilk substitute turning bitter and 'rising' I made a soup recipe the other night (mainly potato, spinach, and veggie broth) that called for buttermilk.  I substituted soymilk and lemon juice, reading online that that was a good substitution for buttermilk.

Now, about 48h of refrigeration later, the leftovers are bitter and a little bit bubbly - it's as if they are 'rising' like a baked good would (I imagine my buttermilk substitute was intended for baking).

What can I put in to stop this chemistry and, for bonus points, nullify the bitterness? It's to the point where it's physically difficult to eat - I'm having trouble keeping the few bites I forced myself through down - but I abhor the idea of wasting food.

(I tagged this baking thinking that people who frequent that tag may have a better than average understanding of the chemistry behind this)

Soy milk is bitter. Enzymes in the beans (lipoxygenase) combine with fats in the presence of water to produce what is usually described as a "beany flavor"; bitter and grassy.

The solution to this problem, although not done in many traditional soy milk preparations, is to cook the soy milk long enough to destroy the enzyme. Many, but not all, soy milk manufacturers will cook the milk as well as add a lot of flavorings to mask the bean flavor.

When enough lemon juice is added to soy milk it will coagulate but in my experience it does not produce flavors more bitter than the milk itself. I have, however, found that, regardless of coagulant, soy milk declines in quality very quickly and, even when I thoroughly boil it to deactivate enzymes and "beany" compounds, it will go from sweet to bitter in just a few days. I have also had homemade soy milk start to turn after a relatively short amount of time developing rancid flavors or activity that implied fermentation such as independently souring or clabbering.

I don't have any proof but based on my own experience I suspect that the lemon is not the culprit. If your milk has become so bitter as to be inedible then I think your soy milk may have spoiled.

As for the foaming- in your comment below you mentioned that the soymilk in question was Silk. Silk is one of the most modified soymilks- they definitely err on the side of flavor rather than simplicity and have a lot of additives for flavor and texture.

One of the additives is Calcium Carbonate. Calcium Carbonate gently coagulates soymilk and is sometimes used for making silken tofu. In Silk it is no doubt used to make the product more creamy.

The existence of Calcium Carbonate in your milk could explain your foaming as it can form CO2 in the presence of acids.

Notes

Soy milk does not coagulate well with lemon juice. It requires a lot of acid to coagulate and so is overly sour and it abruptly produces a very fragile curd. I agree that the advice that you read must have been for baking. If you can't use real buttermilk then in such a dish I would recommend silken tofu for the creaminess and don't worry about the acidity.
In general the way to temper bitterness is to add salt.
As a rule of thumb food that is bitter is often poisonous. I don't imply that that is the case here but you should trust your tongue better and not feel forced to eat questionable food.


How to preserve the green colour of mint when doing spherification? I was recently making some mint spheres using reverse spherification, as a bit of background here was my process: I blended around 15g of mint leaves with 250ml of boiling water and left to steep for an hour. I strained the infusion through a 50 micron filter and then added some sugar, lemon juice and 3.5% calcium gluconolacte before thickening with 0.4% of xanthan gum. The spherification went fine but the colour of the liquid went an unappetising shade of brown and what I would like to know is there a way, aside from adding food colouring, to preserve the mint's green colour?

Plants are green due to the presence of chlorophyll. When chlorophyll is exposed to acids, alkalis, heat or enzymes, it first loses its long hydrocarbon tail, becoming water-soluble instead of fat-soluble. Then, hydrogen ions replace the magnesium atom in the center of the chlorophyll molecule, turning it to pheophythin, which has a dull green-yellow-grey color.

If you insist on continuing the heat treatment, you will lose a lot of the chlorophyll color. You can reduce your loses by using an alkali environment and by adding metal ions. The metal ions part can be as simple as boiling the tea in a copper pot. For alkali, use baking soda. It will turn the leaves into mush (so it is preferable not to use it for vegetables, even though it keeps the color), but it will help with retaining the green. I think that the changed pH shouldn't be a problem, as Lersch's Hydrocolloids says that reverse spherification works at pH levels 2.8-10, but is inhibited by pH below 4. Also, I don't see why you steeped for an hour; normal mint tea is steeped for 5 minutes. If you want stronger tea, use more mint, not longer steeping times.

If you insist on a color coming from mint, but are not particular about steeping, I would suggest getting a mint taste in another way. Juicing the mint will be best, but will require heaps of plant matter, so probably not practicable unless you have access to a mint meadow. It would be much better to rupture the cell walls by freezing, and then leech the mint taste and color in some solvent - water will be OK, alcohol will probably give you a stronger extract. Just steep the defrosted mint for a long time in the water (or alcohol, or mix of both), and then use without adding acids or heating. Again, adding a bit of baking soda may help with the color. But pay attention, if your final product has too high a pH, its taste will be perceived as soapy.

And the easiest solution is, of course, to use food coloring. While some people may consider it unnatural, I don't think it does any bad, especially considering that you are already doing some highly unusual things to your food. It gives you a much easier time with the other aspects of preparation (head and acids).


Why can applesauce be used in place of oil? In many recipes, mostly desserts, it is suggested that you can substitute oil with applesauce to reduce the fat content. But why applesauce?

Is there something special about applesauce or are there other ingredients than can be used?

Fundamentally, the reason for this substitution is that applesauce contains pectin.

In baking, the role of oil is to coat the flour, preventing it from combining with the water (or other wet ingredients) and developing gluten.  Gluten is what causes dough to rise, and also gives elasticity to the final product - what most people think of as "chewiness."

When you're baking, for example, a cake, or even a pie crust, you want to limit the amount of gluten that develops.  A cake or pie crust should be moist, light, and fluffy, not tough and chewy.  When you bite into a cake and find it very dry and bread-like, that is because it has developed a lot of gluten.  A good amount of oil or other fat leads to a lighter, moister, less-glutinous result.

The pectin in applesauce can also, to a certain extent, help to inhibit gluten formation in a dough, but the similarities end there.  I cannot stress this point enough, and I've seen many other online resources get this dead wrong: Pectin (applesauce) is not a straightforward or foolproof substitute for fat.

The mechanisms by which pectin and oil work in this context are completely different:

Oil is a lipid.  Lipids bind to starch (including the ~75% starch in flour) and are hydrophobic - the traditional example of this is dew drops forming on the surface of grass or plants (the latter being the hydrophobe).  In a sense, oil forms a protective "shield" around the flour molecules.
Pectin, on the other hand, is a gelling agent, and specifically a polysaccharide.  Pectin is not hydrophobic and does not actually protect the flour molecules.  In fact, pectin is of the same family as starches, which are also polysaccharides.  What's really happening here is that the pectin competes with the flour for water.  That means less water overall reaches the starch and gluten-forming proteins (giladin and glutenin) in the flour, and because of this, it is not able to develop as much gluten or gelatinize much of the other starch.

What does all of this actually mean for you, the baker?  Quite simply, it means you have to be very careful with this substitution:

Too much pectin can turn your recipe into a jelly-like consistency.
Too little pectin will fail to prevent glutenization (in other words, you'll get bread).
Pectin has the property of syneresis - meaning that once it starts to gel, it also starts to expel liquid, and your dessert will dry out or deflate over time.
Pectin is actually water-soluble at high temperatures (technically, it forms a colloid), it just happens to absorb a lot of water along the way.  Baking for too long, or at too high a temperature, will cause the pectin to break down and dissolve completely, making it useless.

There are also several other problems (or at least "gotchas") when making the apple sauce substitution:

Applesauce is not just pectin.  It has a good deal of water and various proteins and acids, and even a certain amount of lipids.  The exact quantities, however, depend on how the applesauce was made, so it is very hard to get precise control over the amount of pectin, and the textbook 1:1 substitution ratio is almost never correct.
Another thing that applesauce contains is sugar - even unsweetened applesauce.  You will almost certainly need to reduce the amount of sugar elsewhere in your recipe.  This may be difficult, especially if the bulk of the sugar is used as a dry ingredient.
Applesauce behaves somewhat similarly to oil, but do not even try using it as a substitute for any other fat.  Butter, in particular, contains milk proteins which act as natural emulsifiers; pectin does have certain stabilizing properties but is a rather poor emulsifier compared to butter[citation needed].  And it goes without saying that the flavour is substantially different from that of applesauce; oil is "OK" to substitute for because it has very little flavour of its own.

If you plan on using applesauce as a substitute for oil in a recipe that does not specifically explain how to use it as a substitute, then I strongly suggest you do two things:

Don't substitute the entire quantity.  Use 1/2 oil, 1/2 applesauce, or maybe 1/4 oil and 3/4 applesauce.  You will likely also have to lower the total quantity of oil/applesauce to approximately half of what it originally was (give or take 1/4).
If you can, try this substitution on a small scale first, and experiment with the quantities of oil, sugar, and applesauce, before going all-out and putting it into the oven while your guests arrive.  It's very likely that on the first few attempts, you'll end up with something that's palatable, but nowhere near the quality of the oil-based recipe.

Ignore these disclaimers at your own risk!


What do to with cans that you just dented? I just dented ten cans, moderately. Would it be safe to put them straight into the refrigerator or do I have to remove the food from the can and store it some other way?

Background:

I had around 35 cans in one of my side bags on my bicycle. However, I leaned my bicycle against the wall and it fell. The end result was dented cans. What should I do? They still seem good.

If you just damaged previously unharmed cans and they don’t show signs of leakage, the cans should be perfectly safe, even if you store them at room temperature.

The US Department of Agriculture Food Safety and Inspection Service writes:

  If a can containing food has a small dent, but is otherwise in good shape, the food should be safe to eat. Discard deeply dented cans. A deep dent is one that you can lay your finger into. Deep dents often have sharp points. A sharp dent on either the top or side seam can damage the seam and allow bacteria to enter the can. Discard any can with a deep dent on any seam.

So if you inspected the cans and found them ok, I would recommend you

Store them at room temperature, not in the fridge, and
Use them in the near future, not keep them for months or years.

Apart from that, I would probably check the inside of the can when open them, in case the inner lining was damaged and especially acidic foods (think canned tomatoes) caused oxidation or corrosion. I would probably discard them, not because of food safety issues, but because it may cause an unpleasant taste.

For cans with significant damage, the rules for opened cans apply: Don’t store the food in open cans, but empty the content in suitable containers and refrigerate.

——-

Edit, as I had a dented can at hand:

Under normal circumstances, I would probably have left this can at the store. But thanks to the recent wave of panic buying, a family member decided a dented can was better than none.

You can see that the edge of the dent doesn’t affect the seams, so no problem with leakage, and no subsequent food safety issues:

Also, the inner lining is intact, so no risk of the acidic content (tomatoes, in this case) corroding the metal. No problem either:

Still, this was the can I decided to pull first from the pantry, only a week or so after it was bought. I don’t know when the damage happened, though. If I had noticed anything beyond a shape change, I would have discarded the whole can and used another.


Why is my brioche dry? Patient: Brioche. Dry like a croissant. Huge air bubbles.

120 g all purpose flour
96 g heavy cream
1 egg
10g yeast
salt
10 g sugar

Mixed ingredients with lumps, 16h in the fridge, 5h in room temp, into the warm oven meanwhile.

So, how do you think, what did I do wrong?

As per Stephie's comment, I'm adding this as an answer, even though it has to be largely conjectural.

10g of yeast is a lot of yeast for this amount of dough. With a five hour proof at room temperature, I think it is very likely that your dough is overproofed. This means the gluten structure over-develops and then becomes exhausted. So rather than a matrix of small bubbles you get a few big cavities in an otherwise heavy loaf.


Is allspice traditional in the Levant? From the Wikipedia entry for allspice:

  Allspice is also indispensable in Middle Eastern cuisine, particularly in the Levant, where it is used to flavour a variety of stews and meat dishes.

I am confused by this because I thought allspice was a Central American spice. Is this spice an American commodity that has been widely adopted in the Middle East (after the age of exploration), or is there a source of allspice that is native to the Levant?

Allspice is, indeed, the only commonly used spice* native to North America.  It is also very commonly used in various Arabic, Central Asian and Middle Eastern cuisines.  It is a standard part of the cuisine-defining North African spice mixes baharat and ras al hanout.  The vast majority of global Allspice is still grown in Central America.

You ask a good question, because I can't find any information about how it got to North Africa and the Middle East.  Allspice was original brought back to Europe by the Spanish and Portuguese as "Jamaican Pepper" or "myrtle pepper", back when they were still claiming that North America was China/India.

Given this, I have two theories about its introduction into those areas:

Allspice was traded to North African slave traders as part of the slave trade into the Americas in the 17th century.  From there, it spread through the Arabic-speaking world.
Allspice was traded to Indians (who also use it) in exchange for black pepper (just as capsicum peppers were) by the Portuguese.  From India, it spread through the Arabian trade routes of the Indian Ocean.

I don't have any documentary evidence towards either of those theories; my books on the history of spices largely omit allspice.

References:

https://iwp.uiowa.edu/silkroutes/allspice-jamaica-pepper
https://www.britannica.com/plant/allspice
http://theepicentre.com/spice/allspice-2/

(* spice, as opposed to herb or fruit)


Why is a grilled lamb chop tougher than stir fried beef strips or lamb stew? Why does a grilled lamb chop feel more tough compared to say stir fried beef strips or lamb stew?

There are many variables that determine the final texture of cooked meat.  Some of them include how and what the animal was fed, which muscle and how much fat and collagen are present, treatment before cooking, cooking method, length of cooking time and temperature.  The list goes on.  Let's just take your chop vs. stew example.  A lamb chop is relatively lean and cooks quickly.  Stew meat, taken from a different muscle, is relatively fatty and has collagen that is broken down by a slow and lower temperature cook.  The latter is usually more tender because of those variables. (Also see your other question about stir fry).


Non-dairy substitute for cheese on baked potatoes One of the combinations I've missed since becoming dairy-free is grated cheese on baked potatoes. Is there any good substitution for this topping that would provide the salty-tangy counterpoint to the potatoes that I'm looking for?

We've used Daiya dairy-free cheese to make pizza and it's pretty close to the real thing.
http://us.daiyafoods.com/


What Sampling Bread to use for Pulled Pork, open faced? I'm making a bacon based chili with smoked pulled pork (orange juice marinade by injection, smoked dried pusilla/ancho/guajillo rub) where I reserve all the liquid at the end of the process, roux it up into a gravy and fold it back in.

I am entering this stuff into a bacon recipe comp and am looking for a good bread suggestion. I am considering a monterey sourdough loaf wedge for each of the six judges bowl-plates (i.e. heel up and out for effective scooping).

The texture and fit of the bread is great and it is very available, I
am somewhat concerned about the flavor though. For my palette it is
great, but I am looking for additional suggestions on what style of
bread might have that bite of sourdough but maybe match the other
dominant flavors more effectively.
Also, should I back off of the sour, or push it even further?

Additional dominant flavors will include mustard, honey, brown sugar, jalapeno, tien tsin pepper, chocolate, coffee, malty beer, carrot puree and shreds.

It may be a little soft for that compared to most sourdough (but I like a softer bread for something like pulled pork, it competes less for texture), but I'd try a potato based bread.  It's a classic flavor pairing with many of those other flavors (especially bacon!).


Why is it hard to ferment fennel? Fennel seemed like a natural for lacto-fermentation.

There are many recipes with fennel as an ingredient (especially in cabbage kraut), but no one seemed to talk about just fermenting up a big ol' batch of fennel.

So I gave it a spin using my standard brine: 3T kosher salt per quart plus bay leaves, peppercorns, and corriander. I ran one batch with two mason jars of fennel, and a second batch with three.

Of the five jars, three turned out delicious but took a weirdly long time. I left the other two jars running for 5-6 weeks but they didn't show the active bubbling I expect and they never really came together. They were somewhat tart, but their pH was up around 5 instead of down in the 4's where it should have been.

Is there some reason fennel doesn't want to ferment?

After dumping out a couple of jars of failed not-quite-fermented fennel I wondered, "Could fennel have antimicrobial properties?"

<< facepalm >>

Why, yes. Yes it could:

An article on PubMed
Another on PubMed
One on Science Direct
One on Research Gate

Granted, these are about the essential oil and not the whole plant. So I can't be sure this is the problem, but it seems very likely.

Maybe a little fennel mixed in with something else won't muck up the fermentation process, whereas a whole jar of fennel can.

And though it's hard to know, I suppose there could be a safety concern. Lacto fermentation protects us through (1) salt, (2) oxygen depletion, and (3) acid production. Based on what I saw with the failed batches, (2) and (3) may have been below normal. If salt-tolerant critters were to survive... that could be bad.


Open Fire Paella - do I need to fry rice? I often cook a paella outside. I use chicken and prawns. Usually, I fry chicken for 30 mins to brown and cook first - then I remove it. Fry the prawns and remove them, then fry the sofrito. Once that is done I add the rice to fry it a little. Then everything goes back in plus the water.

My question is does frying the rice like this make much difference?

I notice that in "Paella Valencia" all ingredients are kept in the pan, water is added and boiled for a while to ensure chicken is cooked - then rice is added direct to the hot liquid(without frying first) in the pan.

Do you think you get as good a result - it's certainly much easier and uses less dishes!

Do you think you get as good a result

There are lots of different techniques for preparing rice, and all are equally valid. They do lead to different results, but it is up to you do decide which one you prefer. There is not one "right" way we can recommend over the other.

does frying the rice like this make much difference

Yes, there is a noticeable difference. Rice pre-fried in fat has a different texture. It is less fluffy, and can be even slightly slimy if cooked in too much water. It does not dry out as quickly as rice cooked in watery liquid only. It also has a slightly different taste, especially if you use a non-neutral oil. But this difference in aroma may be too subtle to notice if your paella is heavily seasoned, it is most pronounced when the rice is cooked on its own and served as a side.


I have some mesquite smoked brisket and would like to minimize the smoke flavor I have some mesquite smoked beef brisket that is pretty smokey. Is there anything I can do to neutralize that strong flavor?

Smoke flavor is challenging to work with, but I would think an appropriate barbecue sauce would fit the bill.  I wouldn't get anything too salty as I suspect that would worsen the perceived smokiness; but not too sweet because that will just clash with it.

I think a vinegar sauce would be probably best; acidity and bite would help cut through that smokiness.  A mustard sauce also could be a good fit for a similar reason.  (See the Serious Eats guide to barbecue sauces for more details.)


Juice from chicken sous vide Regarding storage of sous vide chicken breasts. Should I store the cooked chicken with its juices (olive oil and chicken juices), or should I remove the breasts from the zip bag, wrap it in film, and store it that way?

Storage is refrigeration.

You can do it either way, but I typically go for convenience.  Remove protein from water bath. Leave in bag. Allow to rest on counter for 15 - 20 minutes. Chill in ice bath.  Refrigerate or freeze. I deal with the contents of the bag at the end.


Israeli soda type drink Recently I had this amazing drink in a "Israeli style bistro" in St Petersburg, Russia. I can't remember the exact name, something beginning with 'J', like Jollo, Jalla or something. It had a really interesting flavour with hints of spices and citrus and it was topped with pistachios, sultanas and pine kernels. It had a delightfully golden brown hue and it was carbonated. Could it be based on an actual traditional Israeli drink? I want to try to make it at home! I already contacted the restaurant but they wouldn't disclose anything about the drink.

What you're describing sounds like jallab. From Will Travel For Food:

  Jallab is a very popular drink in the Middle East. It’s made by diluting the syrup made of grape molasses, dates and rose water with water and serving it in a tall glass with crushed ice. It’s always topped with nuts, most of the time pine nuts and golden raisins, because a jallab without nuts is not really a jallab.

There is also a recipe on the linked page.

Also, from Wikipedia:

  Jallab (Arabic: جلاب / ALA-LC: jallāb) is a type of fruit syrup popular in the Middle East made from carob, dates, grape molasses and rose water.[1] Jallab is very popular in Jordan, Syria, Palestine and Lebanon. It is made mainly of grape molasses, grenadine syrup, and rose water, then smoked with Arabic incense. It is usually sold with crushed ice and floating pine nuts and raisins.

Jallab, the syrup used to make this drink seems to be quite easy to find on the internet. It is also sold in Middle Eastern grocery markets.


Do the herbs which promote relaxation in certain herb teas have more efficiency when theyre warm/hot as opposed to cool/cold? I had made Celestial Seasoning Sleepy Bear tea and left out too long and it got cool, and it just didn't quite have the same affect on me as when I normally drink it.

We're hard-wired to relax with warm drinks, right from our very first hours with mom, so of course, warm beverages tend to be more relaxing than cold ones.

Now for the physics of it all: Heat is an indication of the energy in any given substance. The energy determines how active (and reactive) it is. That is why sugar dissolves more quickly and completely into a hot liquid than into a cold one. When we smell any odor, it is actually molecules of the substance escaping into the air, coming into contact with our nasal sensory apparatus, and being translated by our brains. The hotter the beverage, the more molecules escape into the surrounding air. The more molecules escape the beverage and make contact with our sensory cells, the stronger the smell will be. The more aromatic the tea and the more reactive it is, the greater effect it will have.


Does cooking food destroy BPA? These days, stocking up on and eating canned food to reduce grocery shopping trips is tempting but reports have found possibly BPA can be an issue with eating certain levels of those foods [1]. Aside from if you believe BPA is possibly harmful or not, can cooking food (e.g., from a can) in a non-BPA container help destroy any BPA in the food? If so, what level and type of cooking may be needed, boiling in water on the stove or simply the standard microwave directions on cans?

Reference:
[1] https://www.womenshealthmag.com/food/a19993318/canned-food-safety/

I found some publications about the decomposition of Bisphenols A and E in high-temperature water (BPA: https://doi.org/10.1039/B313509H, BPE: https://doi.org/10.1021/ie060888l). But "high temperature" in their context means 250°C - 300°C (at correspondingly high pressures), while at lower temperatures the reaction rate was practically zero.

Since the reactions described rely on water, dry heating is probably even less successful (and besides, most foods contain water anyway). And I would at least not take it for granted that the decomposition products in either case are less harmful than BPA itself.

So, for household purposes, the answer is clear: No, heating food is not a viable option to destroy BPA.


Boiling peeled peanuts Recently I became interested in making some boiled peanuts for myself, as I have gathered that it is a very cheap, tasty (I like peanuts) and healthy food. However, every recipe that I find involves peanuts in shells. And in my local stores I can only find the raw peanuts without the shell , I will have to spend more effort to get the plain uncooked peanuts with shell.

So, the question is - what is the recipe for boiling peanuts without the shell? (if this is even meaningful to cook them this way).

UPDATE Sorry english is not my native language, so I reworded the question to be clearer.

I have to admit that I have never heard of boiling shelled peanuts, but apparently it's not uncommon.  From ZimboKitchen.com :

Quick Instructions

Get your main ingredient ready – 400 g shelled peanuts. Run them quickly through some water to remove dust and other particles.

Put your peanuts in a medium size pot and add your first 1 ltr of water. Add 1 tsp salt and partially cover your pot and bring to the boil. Add another 1 ltr of water when your initial water is finished.

After an average of 1 1/2 hrs (90min) your peanuts should be boiled and tender to enjoy. If not continue boiling until desired tenderness is achieved.

You may serve your snack and go work or play!

Notes:

You do need raw peanuts.

Other sites use pretty much the same recipe (salt & water), but called for longer cooking time. Some said several hours. I would suggest tasting as you go along and adjust salt and cooking time to your liking.


Cooking beef goulash in a slow cooker with a temperature controller, what temperature? I bought a slow cooker:

and connected it to a temperature controller:

Usually precise temperature control is employed in sous-vide, but I don't want to cook food in plastic bags, only I want to adopt to precise temperature control for making the perfect tender goulash out of cheap goulash beef meat (which can be almost any part of beef which is not nice enough to be sold as a prime part).

I am not going to sear the meat, because of AGEs concern.

So I am cutting the meat into pieces, putting in the slow cooker with vegetables (little or no liquid, the meat and vegetables is gonna give off plenty of its own), and then sticking the temperature controller probe into a piece of meat through a small hole in the lid.

Now I am wondering what temperature and time would be ideal for this exercise? I know I will need to experiment myself, but maybe someone already did this, and if not, at least what values to start experimenting not to have to many failed dinners, and also not have to wait unnecessarily long.

I can probably set it to 65°C (150°F) and wait 3 days, but is it likely to produce a better goulash then some higher temperature at which it will be done in 8 hours? There is probably some point in decreasing temperature and increasing time at which the improvement is infinitesimal or even negative.

Bear in mind in there there are also vegetables like carrots, celery root, parsley root, leeks, radish, swede/rutabaga, and I would prefer them not to be completely unrecognizable.

Here's an older answer to a similar question that is potentially quite relevant. I won't reproduce the text in full, just pull out some of the salient points.

Goulash being a stew, traditionally cooked with tougher cuts much higher in collagen, your ultimate goal is to break down that collagen into gelatin.  Traditional wisdom holds that this breakdown doesn't really begin until about 70°C/160°F, but modernist resources suggest that the actual reaction starts as low as 50°C/122°F and increases exponentially with temperature.  If you're able to maintain a sous vide style temperature using the controller, you should be able to take advantage of similar results.

From @Stefan's linked answer:

  The answer to the question, "how low can you go and still get collagen break-down" I would answer 55°C/130°F or even a bit lower. That is NOT a realistic temperature for cooking a stew, especially not if you will put veggies in it, but as far as collagen breakdown goes that is the lowest temperature for 'stewing meat'.

This also notes the challenge with cooking at such a low temperature: the vegetables won't respond to such a low temperature in the same way as the meat.  They need higher heat and more moisture to break down. You probably need to consider cooking them separately for optimal results:

  I think you must cook the veggies at much higher temperature (80°C-95°C) so you would have to separate the two. If the end result is worth the effort I do not know, I have wanted to try doing a 'stew' with meat cooked sous vide at 55°C - 60°C for 24h+, with the veggies done on the side at 80°C-95°C, normal stew style, to see if it would be better [...]

This is good guidance in my opinion; I'd let the meat go for about 24 hours to start (you could experiement with longer if you like and have the patience to do so) and quickly cook the vegetables on the stove for maybe an hour before you're ready to serve with just as much liquid as necessary.

The only thing you might miss out on with this method is the well-known phenomenon of stews tasting better the day after they're made. If you're going to experiment, consider reserving a portion of the combined result, letting it chill overnight, and then (gently) reheating the next day to see if you get the same "marriage" of flavors.


Why caramel crystallize after adding butter? This weekend I tried making salted caramel following a recipe from Bon Appetit's Test Kitchen (The caramel part from https://www.bonappetit.com/recipe/salted-caramel-chocolate-tart).

I noticed a little foam during the caramel formation but it did not give me much trouble at the moment, but later, when I added the butter, everything has gone awfully bad.

I took it off the stove to add the butter but it started to gain a sandy texture and a light yellow color. I put it on the stove again and kept adding butter hoping to solve it but it did not help.

In the end, I resolved by using half a glass of water, that lowered the temperature and melted everything back to a smooth deep amber sauce. After adding the cream and trying to reduce it to remove the added water, it went ok.

What did I do wrong? What happened?

P.S. In the recipe it asks for cream of tartar but I did not have it so I did not use it, is it the cause? I've seen other recipes without it, so I thought it was ok.

Acids, such as cream of tartar, can interfere with the formation of crystals by inverting sugars. Without it, you need to be more careful/lucky...

To quote Cooks Illustrated [It's for simple syrup but point still holds]:

  Simple syrup crystallizes when enough of the sugar molecules stick to one another that they become insoluble in the water... To find a more effective solution, we had to understand why these additives helped. The cream of tartar and lemon juice are both acids that are able to break down sugar molecules into glucose and fructose in a process called inversion. So not only were fewer sugar molecules available to cluster together in our doctored syrups but the newly present glucose and fructose were physically blocking the remaining sugar molecules from one another.


Risks of allergen cross-contamination (and how to avoid) Is there any evidence regarding the risks of allergen cross-contamination in a typical residential kitchen environment?

Specifically, I'm wondering about situations like:

1) If a seasoned cast-iron skillet comes into contact with an allergen (e.g. gluten, soy), does a risk of cross-contamination still exist after washing/rinsing it? (it seems like it would be unavoidable that some residue gets incorporated into the pan's seasoning layer?)

2) A typical dishwasher may only use a few gallons of water and only perform 2 rinses in a cycle. Is it possible that some low concentration of allergen get "distributed" onto all the dishes and remains after the cycle is complete?

3) For non-porous surfaces (stainless steel, plastic cutting boards), is there any risk of allergens still being present after soap/water cleaning?

4) What about for porous surfaces (wooden cutting boards, wooden stir spoons)?

Ultimately, I'm trying to decide if a food allergy requires that my kitchen be completely devoid of the allergens (or anything that has ever come into contact with them), or if methods like soap+water washing are known to be sufficient to reduce allergen concentration to a safe level.

If you do need indeed an allergen free kitchen, you have to ban the allergen in question from the kitchen. Cross contamination will happen in all situations you describe. Even for non-porous surfaces, your allergens will live on in your dishsponge and get redeposited. The other option beside outright banning is to keep a second set of utensils, dish sponges, towels, etc. which never come in contact with the allergen, and wipe down surfaces and so on before cooking for the allergic person - which is rarely practicable.

The other question is whether you actually need the kitchen to be allergen-free. In typical allergy cases, there is a tollerable daily intake which will not trigger the allergy. It differs by allergen - for example, if you live with a celiac patient, the tolerable bound is so low you will always exceed it if you don't keep the kitchen free of flour. In fact, the flour particles left in the air after baking are sufficient to trigger a celiac episode. But for many other allergens, the person can eat from a contaminated pan, and as long as they are not actively biting into the allergen, it won't cause a reaction.

So, speak to the person you need to protect, and ask what level of cleanliness is needed. You cannot rely on the average tolerable limits per allergen, since some patients react to smaller amounts. They are likely to have been in this situation before and can tell you whether the cross contamination from washed utensils matters to them or not.


How do I feed a sourdough starter? The cookbook I'm using tells me how to make a sourdough starter, but not how to feed it after I take out what I need for the bread. What do I do with the starter once I've used some? I don't think I'll use all of it at once.

When I've made and used starters in the past I've generally fed it 1/2 cup water and 1/2 cup flour every other day.  The challenge with sourdough starters is that you need to be using them regularly as the volume obviously grows if you're just feeding it and not using it regularly.  Of course a friend, family member, or neighbor might be thrilled for you to share it with them but then again...it's kind of like having a pet - you have to keep it fed!


Can I use a flavored liqueur to make vanilla extract? Is it possible to make the extract with Crème De Cacao instead of vodka? I ask because I have some Crème De Cacao that I used in making a Grasshopper pie, but it is only "17.5"% (35 proof)" I don't know if this will be strong enough to do a good job, or should I half it with vodka?

One of the first things you'll need to consider is that the creme de cacao is already chocolate-flavored. Vodka is very clean and neutrally flavored, so if you use it to make an extract you'll get a very pure flavor extraction from whatever you're infusing. If you use something that's flavored already, the end result will obviously contain those flavors too. Basically, extracting vanilla flavor with creme de cacao will not give you a straight "vanilla" extract - it will be "chocolate-vanilla". That's not necessarily a problem, just be sure that you have the right expectation going in.

I do a fair amount of infusion at home (usually for cocktail use rather than baking, but the principles are similar) and have found that flavors tend to be best extracted in spirits that are at least 100 proof (50% alcohol by volume or ABV). Additionally, sugar can inhibit the flavor extraction. This makes your creme de cacao problematic because it's both not strong enough and contains quite a bit of sugar. I don't think you'd get a good extraction by using it on its own.

Simply blending with vodka might help, but only marginally. Most vodka is sold at around 80 proof (40% ABV) so if you did a half-and-half mix, you'd wind up with a solution at around 55 proof (the calculation of ABV isn't purely additive, so calculating the exact ABV would take some math that I'll attempt to add in later once I can track down the formulas). That's not enough of an increase in proof to make much of a difference - might as well just use the vodka at that point.

You could do better by using a stronger spirit. Some brands sell 100-proof vodka which would bring your half-and-half blend up to around 65 proof. It's possible to find some rums and grain spirits sold at 151 proof; blending with those would get you up to around 90 proof. You may even be able to find 190-proof grain alcohol under the Everclear label (though this is illegal in many jurisdictions) which if blended would bring you all the way up to 110 proof, which should be enough for a good extraction even given the sugar content in the mixture.

Of course, if you're going to seek out these specialty products, you could just use them on their own and get a much better, cleaner extract. If you're dead set on using the creme de cacao (or in the general case, any liqueur) you could probably find a way to make it work, but on balance I'd recommend finding a different use for it.


What's the difference between hollandaise, mayonnaise, and aïoli? I was following a recipe by Gordon Ramsay, that included a hollandaise.
However while making it I couldn't help but think I was making a warm mayonnaise.

This brings me to my question: What's the difference between mayonnaise, hollandaise, and aïoli?

(Gordon Ramsay did say he was making a "modern version" of hollandaise using olive oil instead of butter, so I expect what he did isn't a hollandaise in the usual sense?)

Mayo, at its most basic, is egg yolk and oil, with a little vinegar, whipped into an emulsion.

Aioli starts with oil and garlic, and sometimes vinegar or lemon.  Some versions (French-Provençal, apparently) add egg yolk for an end result close to mayonnaise, but the yolk is not required.

Hollandaise is a cooked sauce made from egg yolk and butter, sometimes flavored with lemon and pepper.  I think it must have a much larger ratio of egg yolk to other ingredients in it, since it remains brightly yellow and thick.

Bearnaise is a variation of hollandaise, which uses white wine vinegar to emulsify the egg yolks and butter, and flavors the resulting sauce with shallot, chervil, and tarragon.  Like an aioli, it is not defined by the emulsion but by the flavoring agents.  Adding terragon and capers, or tarragon and shallots, to a hollandaise (or other egg-yolk emulsion sauce) will produce a 'faux-bearnaise'.

The garlic defines the aioli, which is also the only one that can be made without egg yolk. The choice of butter rather than oil makes a hollandaise, and it is cooked as a sauce to set the yolks (which neither of the others require). The yolk and oil combination itself is the central concept of mayonnaise, while it can be flavored, it doesn't have to be.

The sauces are quite similar, though, and an emulsion of egg yolk with seasonings might be called by any name.  The difference between a garlic mayo and a french-style aioli are likely to be pretty subtle.  Likewise, a mayo flavored with lemon and pepper will be hard to distinguish from a hollandaise which uses oil - although hollandaise is usually cooked to set it, so the texture may be different.  And a aioli with butter will be very similar to a hollandaise with garlic.  Adding tarragon and shallot to any of them is likely to produce a bearnaise type sauce.

All three recipes are very loose and broadly defined, since they can be tweaked a lot depending on preferences - so it makes it hard to pin down other factors like ingredient ratios that might distinguish the recipes.  The sauces that add flavorings or substitute ingredients will tend to be named one or the other based more on recipe origin, familiarity, and marketing rather than any clearly defined difference.


What is the biggest safe container for soup? What is the biggest safe container for soup?  The soup comes out of the slow cooker at a high temperature (not measured), but I need to refrigerate it for storage, and that means that it needs to be cooled down rapidly.  That means small containers.

How small should the containers be?  They are standard plastic — I don't have anything fancy.

Currently, I put them into containers and place them in the fridge, but that is all.  Should I cool them in water?

You said the containers are plastic so you have already determined the size of the container. If the containers are clean and sanitary then they are safe. The only important part is cooling the soup down fast enough so it stays out of the "danger zone"; that is, above 40F for more than two hours. So however long that takes will take experimentation or applied physics knowledge or experience.

You can gain experience by heating some water to a simmer as you would for soup (I think). Then see how long it takes you to cool it to 40F. If you can do that in less than two hours, you're cool and safe.


Sourdough bread keeps cracking underneath. What could be the reason? We have been facing this problem as you can see in the image. This dough is 75% hydrated and it is always cooked in a ventilated oven over a baking stone, the temperature of baking is 220° Celsius / 428° Fahrenheit, while it bakes we create steam inside the oven by sprinkling water inside it.
In the beginning of the baking process the oven spring happens accordingly, after a while the oven spring stops upwards and the bread beggins to crack underneath, creating in some cases huge cracks. What can we do to prevent it? What could we having being doing wrong? Thanks in advance

Cracks around the bottom are said to be caused by cold baking sheets. Something about the temperature gradient needs to change. Try baking on a preheated pizza stone.


how to correct a problem with my sourdough starter My boss gave me a sourdough starter that I've had on my counter for a week. I"ve fed it with just equal parts of flour and water without wasting the starter in order to increase the amount. it has increased in the amount, but have I made the starter less effective? My starter does have bubbles and it also has some fluid on top. how can i get what i have ready to use?

When there’s liquid on top your starter it past the really active stage (or you put too much water). If the liquid smells alcoholic, even more so but don’t worry, these beasties are practically indestructible.

You can rejuvenate it by adding a couple of tablespoons of the starter (after discarding the liquid) to equal weights(not volumes) flour and water. I tend to go 40g starter to 80g flour+80g water which I then use to make poolish every 3-4 days or so (which I then use to bake 2 loaves using ~500g of flour). Once I make the poolish, I remove ~40g of flour and the cycle goes on. Remember, no salt goes in the poolish(or starter for that matter)!

If you bake less frequently than every few days go slightly drier: 100g flour/60 water to 40g starter - your starter will stay active for longer but it will also taste more sour as you leave it. If you bake really rarely, like once a month, you can keep it in the fridge and rejuvenate as above a 2ple of days ahead of baking, discarding what remains of 40g.

Finally, if you are wanting to keep a starter with rye, disregard the above- rye tends to mould more easily so you have to be vigilant with your feeds (although you can just give your starter a rye feed every once in a while to no ill effects in my experience)


Why doesn't my Lemon Posset thicken? What am I most likely doing wrong? I've have once succesfully made this Gordon Ramsay's Lemon Posset, but on the last two tries attempts I've not managed to thicken it.

After it has bubbled and kept bubbling for approx. 3 mins, I pour in the lemon juice while stirring, but the substance just doesn't thicken.

What are the most likely things I'm doing wrong? Not stirring strongly enough? Overboiling or underboiling? It did work fine the frist time (sigh)...

It sounds like your problem is most likely lack of acid. The acid is what causes possets to thicken. That could happen because the lemons aren't acidic enough (maybe the ones you had the first time were more sour). Re-reading your recipe, I notice that there's a second, simpler potential cause: your recipe simply asks for the juice of 1-2 lemons, and you might just have smaller lemons, or drier ones without as much juice.

For comparison, I've successfully made this lime and lemon posset, which uses 5 tablespoons of lemon and lime juice for 2.25 cups of cream. That'd scale to 42 mL of lemon/lime juice for your recipe. If you think you simply didn't have as much juice as before, or that the volume was less than that, I'd start by simply using more lemon juice.

If that's not the problem, and your lemons are for some reason less acidic, then the main option is still to use more lemon juice. Ideally you'd concentrate it, though, so that you don't end up with a smaller fraction of cream in the recipe. You can juice more lemons, then reduce the juice on the stove down to the original volume. (An easier option would be to add extra citric acid to your lemon juice, if you happen to have it.)

(Much of this was said in the comments, but I went ahead and made it an answer - please don't accept it unless you verify it though!)


Does adding water back into an over-reduced sauce lose flavour? If I over-reduce a sauce (e.g. a tomato sauce for pasta), so that it is too thick, I'll sometimes add some water in to thin it out again & bring it back to the desired consistency.

Would the resulting sauce be the same in the end as if I reduced it the correct amount originally? Or is there some flavour lost by adding in fresh water later on?

Intuitively, it feels like adding water in would be diluting the sauce, but as I understand it physically, the only thing I've lost by over-reducing is steam, which is pure water? (e.g. if I've made it on stock, any flavour that this has brought has been retained)

What we perceive as "flavor" often comes from a lot of aromatic and volatile components that we smell.  We smell them because they are volatile, which means that they tend to evaporate off food (if they are small molecules) or tend to be carried off of food (for larger molecules).  Aside from the basic  sweet, sour, bitter, salt, and umami notes, the rest of the complexity of flavor comes from smell and volatile flavor molecules.

If the only thing that evaporated when reducing a sauce was "pure water" in the form of steam, you wouldn't be able to smell it.  Yet, when you cook a stock or sauce for a long time, the whole kitchen and house often smells with great aromas.

More aromas in your house means more flavor lost from the sauce.  So, if you do add water back into a sauce, your sauce will often taste somewhat more diluted.  Or, more likely, it will taste "unbalanced," since the smaller flavor molecules tend to escape faster and easier in evaporation.  When we cook down a sauce and concentrate it, we're used to the way the flavors change.  But when you dilute it again, the flavors may not have the same proportion as the original.

All of that said, the magnitude of this effect varies a lot depending on the sauce and types of flavors in it.  If you over-reduce slightly and just add a bit of water back in, it's not likely to make a huge difference.  But if you took a giant pot of flavorful meat stock (which tastes fine as-is), then reduced it down to a demiglace, and then added water back in to try to re-create the original stock, it definitely would taste very different and many flavor notes would be significantly weaker or lost altogether.

As Harold McGee notes in On Food and Cooking (pp. 600-601):

  Slowly simmered until it's reduced to a tenth its original volume,
  stock becomes glace de viande, literally "meat ice" or "meat glass,"
  which cools to a stiff, clear jelly.  Glace has a thick, syrupy,
  sticky consistency thanks to its high gelatin content, about 25%, an
  intensely savory taste thanks to the concentrated amino acids [large,
  non-volatile molecules], and a rounded, mellow, but somewhat flat
  aroma thanks to the long hours during which volatile molecules have
  been boiled off or reacted with each other. ... Intermediate between
  stock and glace is demi-glace or "half-glace" which is stock
  simmered down to 25-40% of its original volume. ... [I]t also has
  the advantage of sparing some of the stock's flavor from being boiled
  off. ... Demi-glace is the base for many classic French brown
  sauces.

Or, listen to James Peterson, author of Sauces: Classical and Contemporary Sauce Making (3rd ed., p. 91):

  Do not overreduce.  Stocks are often reduced to concentrate their
  flavor and to give them an appetizing, light, syrupy texture.
  Although reduction is an almost essential technique for converting
  stocks into sauces, much of the delicacy and flavor of meats is lost
  if reduced too long.  Many of the flavors contained in stock are
  aromatic and evaporate when simmered over a prolonged period, leaving
  a flat taste.

In a later chapter (p. 112), he adds: "Stocks and sauces that have been overly reduced often have a flat, cooked taste that must be offset with more assertive flavors."  As Escoce's answer points out, when you reduce a sauce significantly, it may "overcook" the flavors.  Some of that may be due to browning (Maillard) reactions, but prolonged cooking will also break down some large flavor molecules, again lessening certain flavor notes and altering the balance.  In tomato sauce in particular, you may also break down thickening components (specifically pectin) by overcooking, which will make your sauce more watery.  For vegetable-based sauces, this can often be prevented by boiling the sauce briefly to deactivate enzymes before simmering to reduce.

Because of the flavor changes and loss during reduction, many cuisines around the world have a tradition of adding some "fresh" ingredients near the end of cooking and/or when serving, such as fresh herbs, a spritz of fresh juice, or some chopped fresher vegetables.  The flavors we associate with "fresh" are often the most volatile ones, given off early when a food is first cut or cooked.  Adding them at the end can give a depth of flavor that wouldn't be preserved in a long-cooked reduced sauce.

If you do end up with an overreduced sauce, the flavor is often best salvaged by adding some flavorful new ingredients (as in the Peterson quotation above) or at least adding some more of the "base" back in, such as more stock in a reduced stock or more tomatoes/tomato paste in a tomato sauce rather than plain water.

So, how do you minimize flavor loss when reducing?  It's tough, but it depends on whether more problems are created in flavor loss through evaporation or through chemical changes in the remaining liquid (like flavor molecules breaking down).  In most cases, the evaporation is actually a greater concern when making a sauce, so simmering slowly in a tall pot can help.  The more violent the surface of the liquid is, the more the larger flavor molecules are thrown off and can escape: thus cooking down a sauce at a full boil is usually never good for flavor.  (See above link for more details.)  A taller pot will allow more condensation to occur before the steam leaves the pot, making it more likely that bigger flavor molecules will not have sufficient kinetic energy to escape the pot and/or will be caught in the sort of "rain shower" of condensation and be returned to the liquid.  (This is the same process used in fractional distillation.)  Of course, these also slow down the reduction process, so it's a trade-off in flavor vs. time.


How to reduce the eggs from over burnt at the sides in a wok? I usually throw 3 eggs in a bowl and stir (also known as scrambled eggs) until it become a mixture, then I throw into a wok and fry it. However, I always get the sides (the perimeter or the edges) burnt.

So, how do I prevent the sides from getting over cooked?

I want to cook like the picture below:

I don't want to over fried the edge (or the sides or the perimeter or the outer circle) as shown in the following picture:

You didnt mention what temperature the flame is under your wok. Low, Medium or High. Also Powerburner on some cooktops. Maybe turn the flame down some.