Flavor Perception

The aroma of fmit, the taste of candy, and the texture of bread are examples of flavor perception. In each case, physical and chemical stmctures ia these foods stimulate receptors ia the nose and mouth. Impulses from these receptors are then processed iato perceptions of flavor by the brain. Attention, emotion, memory, cognition, and other brain functions combine with these perceptions to cause behavior, eg, a sense of pleasure, a memory, an idea, a fantasy, a purchase. These are psychological processes and as such have all the complexities of the human mind. Flavor characterization attempts to define what causes flavor and to determine if human response to flavor can be predicted. The ways ia which simple flavor active substances, flavorants, produce perceptions are described both ia terms of the physiology, ie, transduction, and psychophysics, ie, dose-response relationships, of flavor (1,2). Progress has been made ia understanding how perceptions of simple flavorants are processed iato hedonic behavior, ie, degree of liking, or concept formation, eg, crispy or umami (savory) (3,4). However, it is unclear how complex mixtures of flavorants are perceived or what behavior they cause. Flavor characterization involves the chemical measurement of iadividual flavorants and the use of sensory tests to determine their impact on behavior. 

Threshold, Saturation, and Adaptation. Several aspects of flavor perception are not accounted for in the Weber-Stevens laws, eg. 

Exposure to a flavor over time always results in a decrease in the perceived intensity. This dynamic effect of flavorants, called adaptation, is a central part of the process by which people experience flavors in foods as well as in sensory tests. Measuring the dynamics of flavor perception is an emerging technology made possible by inexpensive computing. Called time-intensity analysis, these methods are finding wide appHcations in taste analysis. 

Food colorants play an important role in quality perception. Color is often the first notable characteristic of a food and it influences the expectations of consumers buying the product and also influences food handlers who make quality-related decisions, for example, during visual inspections." More specifically, color predetermines our expectations and perceptions of flavor and taste. " Color is interrelated with flavor intensity (detection threshold), with sweetness and salinity sensations, and also with our susceptibilities to and preferences for products. For example, consumers perceived a strongly red-colored strawberry-flavored drink to be sweeter than a less colored version, and yellow was associated with lemon and pink with grapefruit, but by reversing the colors, flavor perception changed." If food color is not appealing, consumers will not enjoy the flavor and texture of the food. ... 

Tikk, M. Tikk, K. T0rngren, M. A. Meinert, L. Aaslyng, M. D. Karlsson, A. H. Andersen, H. J. Development of Inosine Monophosphate and Its Degradation Products during Aging of Pork of Different Qualities in Relation to Basic Taste and Retronasal Flavor Perception of the Meat. J. Agric. Food Chem. 2006, 54, 7769-1711. 

It has been suggested that these anosmias refer to a primary odor classification. These olfactory sensitivity differences could potentially contribute significant differences in flavor perception among individuals for a given product. 

Figure 1. Representation of the 2-faces of flavor perception showing desirable and undesirable smell (odor) and taste (gustatory) input components.

Flavor perception. See Perception of flavor Flavor quality importance to consumer, 79 in raspberries, s proaches to mapping loci, 109-115... 

Meijboom, P. W. 1964. Relationship between molecular structure and flavor perceptibility of aliphatic aldehydes. J. Am. Oil Chemists Soc. 41, 326-328. 

Smell receptors -flavor perception [FLAVORS AND SPICES - FLAVORS] (Vol 11)... 

Role of Odor in Flavor Perception. In terms of total flavor sensalion. many authorities agree that odor is usually more important lhan taste. Experience, of course, demonstrates the marked reduction of flavor sensation when the nasal passages are partially blocked, as in the case of a common cold. In such instances, the layperson may refer to the "flat taste" of the food. In actuality, the taste buds are functioning normally it is the odor componeni of flavor that is missing. 

Flavor perception results from interactions between a consumer and stimulants in a food. For the aroma part of flavor, the stimulants are volatiles that bind to receptor proteins found on the olfactory epithelium. These stimulants can reach the receptors by two routes, orthonasal or retronasal. The retronasal route is used when odorants are drawn from the mouth during eating through the nasal pharynx to produce aroma. 

Double emulsions are also very useful for food application. Sensitive food materials and flavors can be encapsulated in w/o/w emulsions. Sensory tests have indicated that there is a significant taste difference between w/o/w emulsions and o/w emulsions containing the same ingredients, and that there is a delayed release of flavor in double emulsions [61]. W/o/w or o/w/o multiple emulsions having a concentrated aqueous-soluble flavor or a concentrated oil-soluble flavor encapsulated in the internal phase can be prepared. Food products obtained with these particulates exhibit enhanced flavor perception and extended shelf-life [62]. 

Pet ka, J., Cacho, J., Lerreira, V. (2003). Comparison of flavor perception routes (orthonasal, bucal, retronasal and aftertaste) in a synthetic wine model and with GC-olfactometric data. Oral presentation. Actualites Oenologiques. Bordeaux (Francia). 

Flavor plays a critical role in determining the quality of a food emulsion during consumption. The term flavor refers to those volatile components in foods that are sensed by receptors in the nose (aroma) and those nonvolatile components that are sensed by receptors in the tongue and the inside of the mouth (taste) (122, 123). In addition, certain components in foods may also contribute to flavor because of their influence on the perceived texture (mouthfeel) (124). The flavor of a food is therefore a combination of aroma, taste, and mouthfeel, with aroma usually being the most important (122). Flavor perception is an extremely complicated process that depends on a combination of physicochemical, biological, and psychological phenomena (125). Before a food is placed in the mouth, its flavor is perceived principally through those volatile components that are inhaled directly into the nasal cavity. After the food is placed in the mouth, the flavor is determined by nonvolatile... 

Mouth feel factors are critical in flavor perception. Examples include astringency, pepper bite, menthol cooling, and texture (e.g., softness or hardness as in candy). Sensations, such as crunch after biting into a crisp stick of celery or an apple, contribute to the overall flavor of foods. These mouth feel factors are also... 

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