Food and nutrition
How many new compounds were discovered in maple syrup?
Maple syrup
The basic ingredient in maple syrup is the sap from the xylem of sugar maple or various other species of maple trees. It consists primarily of sucrose and water, with small amounts of the monosaccharides glucose and fructose from the invert sugar created in the boiling process. Organic acids, the most notable one being malic acid, make the syrup slightly acidic. Maple syrup has a relatively low mineral content, consisting largely of potassium and calcium, but also contains nutritionally significant amounts of zinc and manganese. Maple syrup also contains trace amounts of amino acids, which may contribute to the "buddy" flavour of syrup produced late in the season, as the amino acid content of sap increases at this time. Additionally, maple syrup contains a wide variety of volatile organic compounds, including vanillin, hydroxybutanone, and propionaldehyde. It is not yet known exactly what compounds are responsible for maple syrup's distinctive flavour, however its primary flavour contributing compounds are maple furanone, strawberry furanone, and maltol. Maple syrup is similar to sugar with respect to calorie content, but is a source of manganese, with 13 grams containing about 0.44 milligrams, or 22 percent of the US Food and Drug Administration Daily Value (DV%) of 2 milligrams. It is also a source of zinc with 13 grams containing 0.55 milligrams or 3.7 percent of the DV% of 15 milligrams. Compared to honey, maple syrup has 15 times more calcium and 1/10 as much sodium. Scientists have found that maple syrup's natural phenols – potentially beneficial antioxidant compounds – inhibit two carbohydrate-hydrolyzing enzymes that are relevant to type 2 diabetes. In the study, 34 new compounds were discovered in pure maple syrup, five of which have never before been seen in nature. Among the five new compounds is quebecol, a phenolic compound created when the maple sap is boiled to create syrup. British culinary expert Delia Smith described maple syrup as "a unique ingredient, smooth- and silky-textured, with a sweet, distinctive flavour – hints of caramel with overtones of toffee will not do – and a rare colour, amber set alight. Maple flavour is, well, maple flavour, uniquely different from any other." Agriculture Canada has developed a "flavour wheel" that details 91 unique flavours that can be present in maple syrup. These flavours are divided into 13 families: vanilla, empyreumatic (burnt), milky, fruity, floral, spicy, foreign deterioration or environment, maple, confectionery, plants forest-humus-cereals, herbaceous, or ligneous. These flavours are evaluated using a procedure similar to wine tasting. Other culinary experts praise its unique flavour. Maple syrup and its various artificial imitations are widely used as toppings for pancakes, waffles, and French toast in North America. They can also be used to flavour a variety of foods, including fritters, ice cream, hot cereal, fresh fruit, and sausages. It is also used as sweetener for granola, applesauce, baked beans, candied sweet potatoes, winter squash, cakes, pies, breads, tea, coffee, and hot toddies. Maple syrup can also be used as a replacement for honey in wine (mead).