The overall perceived flavor of a food is due to sensory inputs to the brain resulting from the interactions of volatile and nonvolatile food components with odor, taste, trigeminal, and tactile receptors in the nose and mouth before, during, and after mastication (Bell, 1996; Taylor, 1996, 1998; Duran and Costell, 1999; Smith and Margolskee, 2001). Flavor is one of the most important factors determining the perceived quality of foods (Roberts and Taylor, 2000a,b; Gilbert and Firestein, 2002). Consumers expect that each type of food product will have its own particular characteristic flavor profile. For example, a yogurt might be expected to have a ‘‘creamy” ‘‘strawberry” flavor, a fruit beverage to have a ‘‘tangy” ‘‘orangey” flavor, and a cooking sauce to have a ‘‘rich” ‘‘buttery” flavor. A food manufacturer must therefore ensure that the flavor profile of a product is desirable and that it conforms to consumer expectations for that kind of product. A flavor profile may be achieved by incorporating known concentrations of particular types of flavor molecules into a food (e.g., NaCl, sucrose, D-limonene, citric acid) or by using multicomponent ingredients that contain flavor molecules (e.g., lemon juice, herbs, spices, flavor oils, milk fat). Alternatively, the flavor profile of a food might be generated by ingredients that undergo chemical or biochemical reactions during food production, storage, or preparation, for example,
lipid oxidation, browning reactions, or enzymatic reactions (Lindsay, 1996; Jacobsen, 1999; van Ruth et al., 1999a,b; van Ruth and Roozen, 2000). A food manufacturer may therefore wish to know the type and amount of flavoring components that must be incorporated into a food during the manufacturing process in order to produce a desirable flavor profile in the final food product. On the other hand, a food manufacturer may want to know how to avoid the production of an off-flavor within a food during manufacture, storage, or usage.