Flavor maple syrup

It takes 20 to 40 L of sap to yield one liter of maple syrup. To remove the water, you could freeze the sap, as the Native Americans did 300 years ago. The ice that forms is pure water by discarding it, you increase the concentration of sugar in the remaining solution. Large-scale operators today use reverse osmosis to remove about half of the water. The remainder must be boiled off. The characteristic flavor of maple syrup is caused by compounds formed on heating, such as... 

Classify the following as element, compound, or mixture, and justify your classifications salt, stainless steel, tap water, sugar, vanilla extract, butter, maple syrup, aluminum, ice, milk, cherry-flavored cough drops. 

Salt, sodium chloride classification compound. Stainless steel, mix of iron and carbon classification mixture. Tap water, dihydrogen oxide plus impurities classification mixture. Sugar, chemical name sucrose classification compound. Vanilla extract, natural product classification mixture. Butter, natural product classification mixture. Maple syrup, natural product classification mixture. Aluminum, metal classification in pure form—element (sold commercially as a mixture of mostly aluminum with trace metals, such as magnesium). Ice, dihydrogen oxide classification in pure form—compound when made from impure tap water—mixture. Milk, natural product classification mixture. Cherry-flavored cough drops, pharmaceutical classification mixture. 

Maple Svrup. The typical flavor of maple syrup which originates during the heat concentration of maple sap in the presence of air has also been extensively investigated (70-80). Important sugar-based degradation products present in maple syrup include 3-methylcyclopentane-l,2-dione and 2,5-dimethyl-4-hydroxy-3(2H)-furanone. 

It should also be noted that maple syrup contains high molecular weight polysaccharides (80) which probably are also partially degraded during processing and thus can serve as sources for additional flavor compounds. 

Light-colored syrups are generally more difficult to produce, and are very useful in blending of maple syrup to achieve a good color and flavor balance. Lighter syrups therefore generally command a higher price than darker syrups. 

Overall, dozens of compounds are involved in the development of the characteristic flavors found in maple syrup. The number of compounds, the different sap to syrup processing involved, the wide range of maple syrup flavor and intensity, and somewhat frequent off-flavors all complicate the understanding of the flavor of maple syrup. 

There has been some recent research investigating the "Terroir" of maple. Preliminary work has shown that the underlying bedrock composition may influence the chemistry of the sap and resulting syrup (Corbett and Munroe, 2006), but the effects on maple syrup flavor are not as clear (Costanza-Robinson et ah, 2007). 

Maple syrup and maple sugar are often used as flavoring agents in commercial and retail cooking. When added as an ingredient, typically a dark and strong tasting syrup will be used. Maple can add a distinctive flavor to foods, and is also often used as a humectant in some recipes. 

Akochi, K. E., Alii, I., Kermasha, S., Yaylayan, V., and Dumont, J. (1994). Quantitation of alkylpyrazines in maple syrup, maple flavors and non-maple syrups. Food Res. Int. 27,... 

Alii, I., Akochi, K. E., and Kermasha, S. (1992). "Flavor Compounds in Maple Syrup. Developments in Food Science" Vol. 29, pp. 131-140. Elsevier, Amsterdam. 

Belford, A. L., Lindsay, R. C., and Ridley, S. C. (1991). Contributions of selected flavor compounds to the sensory properties of maple syrup.. Sens. Stud. 6,101-118. 

Caramel is unintentionally generated in burnt carbohydrate foods (rice, oatmeal, cornmeal, etc.) and molasses (Kowkabany et al., 1953) it is the source of maple flavor and color in the concentration of maple sap to maple syrup (Stinson and Willits, 1965). In industrial manufacturing, the intended application is taken into account, because reaction conditions help determine the properties of the pyrolysate, e.g., its tinctorial value, water solubility, and alcohol stability. Tinctorial value refers to the absorbance at 560 nm of a 0.1-wt/vol% solution in a 1-cm cell. Tinctorial strength increases with acidity, temperature, and duration of heating. Caramel manufactured above pH 6.3 is biologically unstable and much below pH 3.1, it is a resin. 

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