With the interest of producing inexpensive replacements for expensive natural flavorings, chemists have intensively studied flavor precursors and their sensory and chemical characteristics produced upon fermentation or heating. Through model reactions of carbohydrates, proteins and lipids, we have gained great insight as to the contribution to flavor of given precursors in a particular foodstuff.
Leucine and glucose mixtures are commonly employed as a foundation for the compounding of cocoa reaction flavors. Comprehensive studies on the volatile flavor products produced between these compounds when heated is not available in literature. Shigematsu et al. (1971) reported the prodction of 2-(5 -hydroxymethyl-2-formylpyrol-1-yl)-isocaproic acid, lactone upon dry reaction of leucine and glucose at 200°C. They described the flavor of this lactone to be miso, soy sauce and a little chocolate-like.
This paper reports the identification of volatile compounds resulting from the reaction of leucine and glucose in the common food-grade solvent propylene glycol.