Flavors primary taste

A persistent idea is that there is a very small number of flavor quaUties or characteristics, called primaries, each detected by a different kind of receptor site in the sensory organ. It is thought that each of these primary sites can be excited independently but that some chemicals can react with more than one site producing the perception of several flavor quaUties simultaneously (12). Sweet, sour, salty, bitter, and umami quaUties are generally accepted as five of the primaries for taste sucrose, hydrochloric acid, sodium chloride, quinine, and glutamate, respectively, are compounds that have these primary tastes. Sucrose is only sweet, quinine is only bitter, etc saccharin, however, is slightly bitter as well as sweet and its Stevens law exponent is 0.8, between that for purely sweet (1.5) and purely bitter (0.6) compounds (34). There is evidence that all compounds with the same primary taste characteristic have the same psychophysical exponent even though they may have different threshold values (24). The flavor of a complex food can be described as a combination of a smaller number of flavor primaries, each with an associated intensity. A flavor may be described as a vector in which the primaries make up the coordinates of the flavor space. 

Multiple senses, including taste, contribute to our total perception of food. Our perception of the flavor of food is a complex experience based upon multiple senses taste per se, which includes sweet, sour, salty and bitter olfaction, which includes aromas touch, also termed mouth feel , that is, texture and fat content and thermoreception and nociception caused by pungent spices and irritants. Taste proper is commonly divided into four categories of primary stimuli sweet, sour, salty and bitter. One other primary taste quality, termed umami (the taste of L-glutamate), is still somewhat controversial. Mixtures of these primaries can mimic the tastes of more complex foods. 

The chemical, instrumental and sensory data presented above indicated that storage of cooked beef affects the lipid composition and concomitantly, the flavor of beef. The data also indicated that primary tastes like bitter and sour are affected by storage. 

Indeed, potatoes are rather neutral in flavor, but they contain typical taste and odor substances. Their overall acceptance in the U.S. and in Europe is very high Q ), higher than for many other commodities. A bland food would never obtain such a high acceptability. However, according to Burr (2) none of the four primary taste sensations of sour, solty, sweet and bitter is ordinarily perceptible in normal cooked potatoes. 

Potato taste is not characterized by one of the primary taste sensations. Especially sweet, sour or bitter notes are considered off-flavors. However, free amino acids and 5 -nucleotides are important compounds that convey an agreeable basic taste to potato products. The amino acids occur naturally in free form the 5 -nucleotides are liberated during the heat preparation of potatoes by a specific enzymatic degradation of RNA. Starch forms a matrix for all potato preparations. Although it is tasteless, is has an influence on taste quality due to textural characteristics, and due to its pronounced capability to form stable complexes with flavor compounds either in a thermal gradient or under isothermal conditions. 

A number of compounds have the ability to enhance or improve the flavor of foods. It has often been suggested that these compounds do not have a particular taste of their own. Evidence now suggests that there is a basic taste response to amino acids, especially glutamic acid. This taste is sometimes described by the word umami, derived from the Japanese for deliciousness (Kawamura and Kare 1987). It is suggested that a primary taste has the following characteristics ... 

Melon, Cucumis melo, is a member of the Cucurbitaceae family and grows best in tropical regions. The pulp of the fruit has pleasant flavor and taste, and the seeds are generally treated as waste however, medicinal effects have been reported for the seeds (24, 25). Hexane-extracted seed oil of Cucumis melo hybrid AF-522 was determined to contain 64 g of linoleic acid per 100 g of total fatty acids (Table 4) (24). Significant amounts of oleic, palmitic, and stearic acids were also detected in the melon seed oil. The specific gravity (28°C), refractive index (28°C), and iodine value of the seed oil were 0.9000, 1.4820, and 112, respectively, under the experimental conditions (24). Earlier in 1986, Lazos (25) extracted the oil from Cucumis melo seeds and examined its physicochemical properties (25). Linoleic acid was the primary fatty acid and accounted for 64.6% of the total fat (w/w), along with 20.1% oleic acid, and 14.7% total saturated fatty acids (Table 4). Iodine value and refractive index (40°) of the seed oil were 124.5 and 1.4662, respectively. 

Table 1 Primary taste and flavor characteristics of typical flavor ingredients...

Ingredient Sweet Primary taste Bittersweet Bitter Flavor characteristic... 

The type of sweetness varies with the different sugars (27), The sweetness of sucrose is quickly perceived and promptly reaches a maximum intensity, whereas the sweetness of dextrose stimulates the taste organs more slowly and reaches a maximum intensity later. The primary taste of glucose (14) is sweet but the secondary tastes are bitter, sour, or tart, while in the case of sucrose secondary flavors are absent. 

The blended complex of primary taste factors might be called the platform on which the Flavor Profile is built and, as such, it plays a fundamental role in developing interesting and mouth-satisfying flavors. 

There are five primary taste sensations including sweet (carbohydrate based molecules), sour (acidic concentration), salty (sodium chloride), bitter (quinine and other basic functionalities) and umami (salts of glutamic acid). The human tongue does not discriminate every chemical substance composing a flavor it decomposes the taste of foodstuffs into the five basic taste qualities, instead. A single taste bud contains 50-100 taste cells representing all 5 taste sensation. An adult has about 9000 taste buds. 

Beer flavor. Primary odor and taste substances from malt and hops determine the type of beer bitter substances (see humulone) and aroma substances of hops characterize Pilsener beer, a relatively high content of Furaneol provides the caramel note of dark beer. The most important aroma substances in light full beer are... 

With the exception of the four primary taste sensations— sweet, bitter, salty, and sour—food flavors are the result of our sense of smell. Today, chemists can make chemicals in the laboratory which alone or in various combinations can imitate many of the natural food flavors. These are synthetic flavors. In many cases the synthetic flavors are superior to natural flavors in terms of (1) withstanding processing, (2) cost, (3) availability, and (4) consistent quality. Synthetic flavors may be substances that are prepared in the laboratory but chemically identical to those found in nature, or substances prepared in the laboratory which as yet have not been found to occur in nature but which produce familiar aromas. 

The primary appHcation for barrier polymers is food and beverage packaging. Barrier polymers protect food from environmental factors that could compromise both taste and shelf life. They also help retain desirable flavors and aroma. Barrier polymers are also used for packaging medical products, agricultural products, cosmetics, and electronic components and in moldings, pipe, and tubing. 

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... 

When the antioxidants were used in the cooked/stored samples, data indicated that they were very effective in inhibiting lipid oxidation and MFD. The chemical and off-flavor indicators were reduced and the on-flavor notes were increased. Thus, phenolic-type primary antioxidants that function as free radical scavengers are very effective tools for preventing lipid oxidation and MFD in ground beef. It should also be noted that the intensity of the desirable flavor notes remained at very high levels, which meant that the patties retained their beefy tastes. Therefore, for an antioxidant to be highly effective, it should not only prevent lipid oxidation, but it should also retain the desirable flavor properties of the food commodity. 

Nature-identical aroma substances are, with very few exceptions, the only synthetic compounds used in flavors besides natural products. The primary functions of the olfactory and taste receptors, as well as their evolutionary development, may explain why artificial flavor substances are far less important. The majority of compounds used in fragrances are those identified as components of natural products, e.g., constituents of essential oils or resins. The fragrance characteristics of artificial compounds nearly always mimic those of natural products. 

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