Perception of flavor

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. 

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. ... 

Human perception of flavor occurs from the combined sensory responses elicited by the proteins, lipids, carbohydrates, and Maillard reaction products in the food. Proteins Chapters 6, 10, 11, 12) and their constituents and sugars Chapter 12) are the primary effects of taste, whereas the lipids Chapters 5, 9) and Maillard products Chapter 4) effect primarily the sense of smell (olfaction). Therefore, when studying a particular food or when designing a new food, it is important to understand the structure-activity relationship of all the variables in the food. To this end, several powerful multivariate statistical techniques have been developed such as factor analysis Chapter 6) and partial least squares regression analysis Chapter 7), to relate a set of independent or "causative" variables to a set of dependent or "effect" variables. Statistical results obtained via these methods are valuable, since they will permit the food... 

The perception of flavor is a fine balance between the sensory input of both desirable and undesirable flavors. It involves a complex series of biochemical and physiological reactions that occur at the cellular and subcellular level (see Chapters 1-3). Final sensory perception or response to the food is regulated by the action and interaction of flavor compounds and their products on two neur networks, the olfactory and gustatory systems or the smell and taste systems, respectively (Figure 1). The major food flavor components involved in the initiation and transduction of the flavor response are the food s lipids, carbohydrates, and proteins, as well as their reaction products. Since proteins and peptides of meat constitute the major chemical components of muscle foods, they will be the major focus of discussion in this chapter. 

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

Fat also functions as a coating for the flavor receptors in the mouth, effectively slowing the perception of the flavor. Again, the absence of fat results in a quick perception of flavor that often seems unnatural. 

The color of citric beverages, in particular, is related to the consumer s perception of flavor, sweetness, and other characteristics in relation to the quality of these products (Tepper, 1993 Cortes, Esteve, and Frigola,... 

In cheese, a matrix effect could modulate salty and bitter perception in different ways and evolve during the maturation process. The composition of the matrix and physiological parameters had to be taken into account to better understand temporal release and perception of flavor. The study of the relationships between sensory and aroma release gave reliable results only for sulfury note which was the most intense and due to well identified and specific compoimds. 

Food products, whether fresh or processed, must have desirable flavors that are pleasant to the palate of the consumer. Flavorings are often added to foods, to create a totally new taste, to enhance or increase the perception of flavors already present, to replace unavailable flavors, to mask less desirable flavors that are naturally present in some processed foods, or, to supplement flavors already present and that had disappeared as a result of food processing [4]. 

Carbohydrates can have a measurable influence on the release and perception of flavors. Carbohydrates change the volatility of compounds relative to water, but the effect depends on the interaction between the particular volatile molecule and the particular carbohydrate. As a general rule, carbohydrates, especially polysaccharides, decrease the volatility of compounds relative to water by a small to moderate amount, as a result of molecular interactions. However, some carbohydrates, especially the monosaccharides and disaccharides, exhibit a salting-out effect, causing an increase in volatility relative to water (Godshall, 1997). 

Flavor is a combination of taste, sensation, and odor transmitted by receptors in the mouth (taste buds) and nose (olfactory receptors). The stereochemical theory of odor is discussed in the essay that precedes Experiment 16. The four basic tastes (sweet, sour, salty, and bitter) are perceived in specific areas of the tongue. The sides of the tongue perceive sour and salty tastes, the tip is most sensitive to sweet tastes, and the back of the tongue detects bitter tastes. The perception of flavor, however, is not so simple. If it were, it would require only the formulation of various combinations of four basic substances—a bitter substance (a base), a sour substance (an acid), a salty substance (sodium chloride), and a sweet substance (sugar)—to duplicate any flavor In fact, we cannot duplicate flavors in this way. The human possesses 9,000 taste buds. The combined response of these taste buds is what allows perception of a particular flavor. 

Auvray M, Spence C (2008) The multisensory perception of flavor. Conscious Cognit 17(3) 1016-1031... 

CE Wilson, WE Brown. Influence of food matrix structure and oral breakdown during mastication on temporal perception of flavor. J Sensory Stud 21 69-86,... 

A prototype system using computer-controlled syringe pumps to deliver up to four streams of stimuli simultaneously was developed. This prototype has been used to investigate the perception of flavor mixtures over time. Results are presented here for experiments looking at (a) adaptation to flavors delivered in this fashion and (b) the nature of taste-aroma interactions in a strawberry flavored solution that comprised a commercial strawberry flavor, sucrose, and organic acids in solution. 

KGC Weel, AEM Boelrijk, AC Alting, PJJM van Mil, JJ Burger, H Gruppen, AGJ Voragen, G Smit. Flavor release and perception of flavored whey protein gels Perception is determined by texture rather than by release. J Agric Food Chem 50(18) 5149-5155, 2002. 

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