question: Why does microwaving bread (namely French Bread) make it rubbery, as opposed to toasting it?
comment: [Startch gelatinization]( URL_0 ) is the process by which the starch in flour absorbs water and attains the structural composition found in bread. This process is triggered by heat. Microwaved bread has already gone through this process once (during the initial baking) so it contains less water. The gelatinization still occurs, but the lack of available water results in the starch essentially being boiled. The starch dries and hardens slightly once the bread is out of the microwave, leading to chewiness. You can avoid chewy bread by laying a damp paper towel over whatever you’re microwaving. The same reaction happens in the toaster, but it’s more extreme and more localized. A crispy piece of toast has also lost a lot of water, but the heat has been applied mainly to the exterior - hence why the crust and face of toast are always crispy, but an underdone piece of toast might still be “bread-y” on the inside.
passages: Freeze-tolerant solar water-heating panels exploit the elasticity of silicone to repeatedly accommodate the expansion of water on freezing, while its extreme temperature tolerance maintain a lack of brittleness below freezing and excellent tolerance of temperatures in excess of . Its property of not having a carbon backbone, but a chemically robust silicon backbone instead, reduces its potential as a food source for dangerous waterborne bacteria such as Legionella.
   Section::::Curing.:Condensation cure system.
   Chemically, silicone rubber is a family of thermoset elastomers that have a backbone of alternating silicon and oxygen atoms and methyl or vinyl side groups. Silicone rubbers constitute about 30% of the silicone family, making them the largest group of that family. Silicone rubbers maintain their mechanical properties over a wide range of temperatures and the presence of methyl-groups in silicone rubbers makes these materials extremely hydrophobic, making them suitable for electrical surface insulations.
   "Condensation curing" systems can be "one-part" or "two-part" systems. In one-part or "RTV" (room-temperature vulcanizing) system, a cross-linker exposed to ambient humidity (i.e., water) experiences a hydrolysis step and is left with a hydroxyl or silanol group. The silanol condenses further with another hydrolyzable group on the polymer or cross-linker and continues until the system is fully cured. Such a system will cure on its own at room temperature and (unlike the platinum-based addition cure system) is not easily inhibited by contact with other chemicals, though the process may be affected by contact with some plastics or metals and may not take place at all if placed in contact with already-cured silicone compounds. The crosslinkers used in condensation cure systems are typically alkoxy, acetoxy, ester, enoxy or oxime silanes such as methyl trimethoxy silane for alkoxy-curing systems and methyl triacetoxysilane for acetoxy-curing systems. In many cases an additional condensation catalyst is added to fully cure the RTV system and achieve a tack-free surface. Organotitanate catalysts such as tetraalkoxy titanates or chelated titanates are used in alkoxy-cured systems. Tin catalysts such as dibutyl tin dilaurate (DBTDL) can be used in oxime and acetoxy-cured systems. Acetoxy tin condensation is one of the oldest cure chemistries used for curing silicone rubber, and is the one used in household bathroom caulk. Depending on the type of detached molecule, it is possible to classify silicone systems as acidic, neutral or alkaline. 
   The problem can be partially solved by replacing Cb with silica, because it enables the production of "green" tires that display both improved wet grip properties as well as a smaller rolling resistance.
   Bread toasted in a conventional toaster can "sweat" when it is served (i.e. water collects on the surface of the cooled toast). This occurs because moisture in the bread becomes steam while being toasted due to heat and when cooled the steam condenses into water droplets on the surface of the bread.
   Toasted bread slices may contain Benzo["a"]pyrene and high levels of acrylamide, a carcinogen generated during the browning process. High acrylamide levels can also be found in other heated carbohydrate-rich foods. The darker the surface colour of the toast, the higher its concentration of acrylamide. That is why, according to the recommendations made by the British Food Standards Agency, bread should be toasted to the lightest colour acceptable.
  
  Section::::Cultural references.
   Section::::Description.
   BULLET::::- Strong adhesion to matrix
  
  BULLET::::- Similar viscosity to matrix at processing temperature
  
  Cyclic olefin copolymer, an optically transparent plastic with low moisture uptake and solvent resistance among other useful properties, can be toughened effectively with a styrene-butadiene-styrene rubber with the above properties. The Notched-Izod strength more than doubled from 21 J/m to 57 J/m with an optical haze of 5%.
  
  Section::::Sample Applications of Rubber Toughening.:Improving polystyrene.
   More than two layers of material can be welded at once. The materials to be welded experience similar vibrations to those in plunge welding but shorter in time. Hold force to the newly welded region is provided by previously welded section that has come out of the tooling and cooled down.
   In general, treating indefinitely with concentrations below 110°Tw (64%) only swells and shrinks the fabric, while higher concentrations produce the stiff, translucent parchment-like effect in a few seconds, with some loss of tensile strength.
   Section::::Toughening Mechanisms.:Cavitation.
   Around 200 °C in oxygen-containing atmosphere, PDMS releases traces of formaldehyde (but less than other common materials such as polyethylene ). At 200 °C, silicones were found to have lower formaldehyde generation than mineral oil and plastics (less than 3 to 48 µg CHO/(g·hr) for a high consistency silicone rubber, versus around 400 µg CHO/(g·hr) for plastics and mineral oil). By 250 °C, copious amounts of formaldehyde have been found to be produced for all silicones (1,200 to 4,600 µg CHO/(g·hr)).
  
  Section::::See also.
  
  BULLET::::- Injection molding of liquid silicone rubber
  
  Section::::External links.
  
  BULLET::::- Science of Silicone Polymers (Silicone Science On-line, Centre Européen des Silicones – CES)
   That is, the patent described a sandwich with a layer of filling in between two pieces of bread which are crimped shut and have their crust removed. The other nine claims of the patent elaborate the idea further, including the coating of two sides of the bread with peanut butter first before putting the jelly in the middle, so that the jelly would not seep into the bread—the layers of filling "are engaged to one another to form a reservoir for retaining the second filling in between".
   Section::::Polymerization of butadiene.
   Once mixed and coloured, silicone rubber can be extruded into tubes, strips, solid cord or custom profiles according to the size specifications of the manufacturer. Cord can be joined to make O-rings and extruded profiles can be joined to make seals. Silicone rubber can be moulded into custom shapes and designs. Manufacturers work to set industry tolerances when extruding, cutting or joining silicone rubber profiles. In the UK this is BS 3734, for extrusions the tightest level is E1 and the widest is E3.
   BULLET::::2. They are not subject to shrinkage and microleakage, as the bonding mechanism is an acid-base reaction and not a polymerization reaction.(GICs do not undergo great dimensional changes in a moist environment in response to heat or cold and it appears heating results only in water movement within the structure of the material. These exhibit shrinkage in a dry environment at temperature higher than 50C, which is similar to the behavior of dentin.
   BULLET::::- Silicone: Silicone bakeware is light, flexible and able to withstand sustained temperatures of 360 °C (675 °F). It melts around 500 °C (930 °F), depending upon the fillers used. Its flexibility is advantageous in removing baked goods from the pan. This rubbery material should not to be confused with the silicone resin used to make hard, shatterproof children's dishware, which is not suitable for baking.
  
  Section::::Types of cookware and bakeware.
   Section::::Characteristics of the continuous phase relevant to toughening theory.:Glass Transition Temperature.
   In addition, conventional rubber undergoes a glass transition (often called a "rubber-glass transition"). E.g. The Space Shuttle "Challenger" disaster was caused by rubber O-rings that were being used well below their glass transition temperature on an unusually cold Florida morning, and thus could not flex adequately to form proper seals between sections of the two solid-fuel rocket boosters.
  
  Section::::Applications.:Materials science.:Sol-gel.
   In Marcel Proust's novel "In Search of Lost Time", one of the narrator's childhood memories sets in while tasting a madeleine dunked in tea. The soft, spongy consistency of the madeleine could seem like an odd choice as dunking is more common with crisp baked products, such as biscuits. In fact, draft versions of Proust's manuscript reveal that the author initially had the narrator dunk a piece of toasted bread.
   A piece where the singer speaks fondly to a sister that has come back from a trip to English Canada. Singer Karl Tremblay famously likes to make a humorous political statement on stage by replacing the verse "Promise me that this time, you're staying home for good" by "Promise me that you didn't turn into a federalist, little dammit!" (listen)
  
  Section::::Songfacts.:"La Manifestation".
  
  It comically chronicles a public protest, led by "a guy that thought he was Castro", that ends up being a major disappointment and disillusionment. (listen)
  
  Section::::Songfacts.:"L'Hiver Approche".
   BULLET::::- Rubber: Biodiesel also affects types of natural rubbers found in some older engine components. Studies have also found that fluorinated elastomers (FKM) cured with peroxide and base-metal oxides can be degraded when biodiesel loses its stability caused by oxidation. Commonly used synthetic rubbers FKM- GBL-S and FKM- GF-S found in modern vehicles were found to handle biodiesel in all conditions.
  
  Section::::Technical standards.
  
  Biodiesel has a number of standards for its quality including European standard EN 14214, ASTM International D6751, and others.
  
  Section::::Low temperature gelling.
   BULLET::::6. Quenching - The reaction is quickly quenched at 0 °C, and followed by the addition of the same polymerase mix. The MALBAC primers efficiently bind to both semi-amplicons and genomic DNA template.
  
  BULLET::::7. Extension - "Bst" DNA Polymerase (Large Fragment) extends the primers at 65 °C for 2 mins. At this step, full-amplicons are made for those that used semi-amplicons as templates, and also semi-amplicons are made for those that used the genomic DNA template as templates.
  
  BULLET::::8. Melting – The reaction is heated to 94 °C to separate the amplicons from the template.
   In response to the new prior art cited, Smucker's narrowed the wording of their claims to only cover a very specific version of their sealed crustless sandwich. The more narrow claims, for example, only cover sealed crustless peanut butter and jelly sandwiches where the jelly is held between two layers of peanut butter. Nonetheless, in December 2003, the patent examiner rejected the narrowed claims in light of the new prior art.
  
presuppositions: Bread reacts differently to a microwave and toaster. 
corrections: Bread reacts the same to both toaster and microwave, however this reaction is more extreme and localized from a toaster. 
raw_presuppositions: Bread reacts differently to a microwave and toaster.  Microwaves should heat up the bread and toast it.
raw_corrections: Bread reacts the same to both toaster and microwave, however this reaction is more extreme and localized from a toaster.  Bread lacks a lot of water, so the starch in the bread is boiled when it is microwaved, resulting in chewy bread.