Flavor alcohol contribution

The development of characterizing fish aromas and flavors Involve both enzymic and nonenzymlc oxidative reactions. Llpoxygenase-derlved carbonyls and alcohols contribute the distinctive planty-green aroma notes to fresh fish that vary with species with regards to compounds and concentrations. 

Soybean concentrate production involves the removal of soluble carbohydrates, peptides, phytates, ash, and substances contributing undesirable flavors from defatted flakes after solvent extraction of the oil. Typical concentrate production processes include moist heat treatment to insolubilize proteins, followed by aqueous extraction of soluble constituents aqueous alcohol extraction and dilute aqueous acid extraction at pH 4.5. 

The food flavor industry is the largest user of vanillin, an indispensable ingredient in chocolate, candy, bakery products, and ice cream. Commercial vanilla extracts are made by macerating one part of vanilla beans with ten parts of 40—50% alcohol. Although vanillin is the primary active ingredient of vanilla beans, the full flavor of vanilla extract is the result of the presence of not only vanillin but also other ingredients, especially Httle-known resinous materials which contribute greatly to the quaUty of the flavor. 

Yeast (qv) metabolize maltose and glucose sugars via the Embden-Meyerhof pathway to pymvate, and via acetaldehyde to ethanol. AH distiUers yeast strains can be expected to produce 6% (v/v) ethanol from a mash containing 11% (w/v) starch. Ethanol concentration up to 18% can be tolerated by some yeasts. Secondary products (congeners) arise during fermentation and are retained in the distiUation of whiskey. These include aldehydes, esters, and higher alcohols (fusel oHs). NaturaHy occurring lactic acid bacteria may simultaneously ferment within the mash and contribute to the whiskey flavor profile. 

In the algebraic system discussed previously, x is a factor its value determines what the particular result y will be. Yeast and fruit are factors in the wine-making process the type and amount of each contributes to the alcohol content and flavor of the final product. 

Meat flavor deterioration (MFD), formerly referred to as warmed-over flavor, is described as the loss of desirable meaty flavor with an increase in off-flavors (i-5). During this process, the increase in off-flavors is primarily contributed by hpid oxidation reactions. As lipids oxidize, they produce mixtures of aldehydes, ketones and alcohols that contribute to the off-flavors observed. Many of these compounds have been identified and the increase in their intensities during storage have been well documented (7, 4-6),... 

Once the lactic add and alcohol fermentation is complete, the moromi is aged until its moldy odor has disappeared. During this portion of the aging period other flavor molecules, particularly 4-ethylguaiacol and 4-ethylphenol are added to the moromi by Candida versatilis (4), These compounds are the major components contributing to the flavor of soy sauce. The entire moromi process is completed in about six months. 

Acetals derived from aliphatic aldehydes have odor characteristics that resemble those of the aldehydes but are less pronounced. These acetals contribute to the aroma of alcoholic beverages, but can rarely be used in flavoring compositions because they are not sufficiently stable. Since they are resistant to alkali, a number of them (e.g., heptanal dimethyl acetal and octanal dimethyl acetal) are occasionally incorporated into soap perfumes. 

Recent developments In microcomputers, sensory analysis and experimental design have made it possible to efficiently evaluate and optimize products. This paper focuses on the conduct and analysis of a study to optimize the flavor constituents of an alcoholic "digestive" liqueur. It illustrates the use of the panel data, and the contributions of the microcomputer as both a tool for gathering data, and as an inexpensive replacement for mainframe computers in statistical computations. 

The 55% ethanol extracted 6.91% of the weight of average oven-dry American oak (Table III). In flavoring 1 liter of California port wine for one taster, an average of 575 mg of this wood, 38 mg of its solid, or 13 mg of its phenols extractable by 55% alcohol produced a just detectable difference. A series of five samples of European oak in comparable analyses averaged 11.37% extractable solids, and 1 liter of the same port wine was just detectably flavored by 515 mg of oven-dry wood, 51 mg of extractable solid, or 30 mg of phenol. The fact that European oak contributes more extract and more tannin to wine and yet, per unit of extract or phenol, less flavor is clear from these data. This agrees with tasters opinions and is believed to be because American oak contributes considerably more oak odor per unit of tannin. The amount of flavor per unit of wood is about the same, but the European oak counteracts less flavor per unit of extract by its high extract content. In other tests, 12% alcohol removed 49% as much extract as did 55% alcohol from American oak and 71% as much from French. In earlier tests (47) about 63% as much extract was obtained from American oak by 12% alcohol as by 55% alcohol. Whether these extracts would have the same flavor value has not yet been studied. 

In an alcohol-free beer, the concentrations of the beer odorants were 5 to 10-fold lower than in the pale lager beer [18] suggesting that the former beer is a very appropriate matrix for the determination of odor thresholds. A determination of the odor thresholds in the alcohol-free beer revealed (Table 15) that, compared to water, the odor threshold of all odorants increased, but to a different extent. For instance, the threshold of (E)-B-damascenone increased by a factor of 2500, while that of HDF was enhanced only by a factor of eight. Odor activity values calculated on the basis of the odor thresholds in the alcohol-free beer (Table 15) now confirmed the significant contribution of HDF to the dark beer flavor. 

It should be stressed that it is a prerequisite of successful flavor precursor studies that the contribution of the odorant under investigation to a food flavor or off-flavor has been established. Sometimes the structure of a precursor can be assumed on the basis of structural elements in the odorant. In such cases, additions of the respective isotope-labelled precursor to the food system is commonly used to elucidate the precursor and to clarify reaction pathways governing the formation of the odorant. This method has been frequently applied, especially, in studies on the enzymatic generation of odor-active aldehydes (e.g., (Z)-3-hexenal in tea leaves) or alcohols (e.g., l-octen-3-oI in mushrooms) [cf. reviews in 84, 85] as well as lactones [86] from unsaturated fatty acids. 

Aldehydes are volatile substances found (along with alcohols, ketones, and esters) in minute amounts and contributing to the formation of odor and flavor of plant parts. Plants containing aldehydes with anticancer properties include the following ... 

Vermouth contains ethanol, sugars, acids, minerals, higher alcohols, phenols besides a large number of minor compounds that contribute to the unique taste and flavor of the beverage. However, it is the spices and... 

The more concentrated di-, triphenols, furanaldehy-des and -alcohols, pyrazines and pyrroles possess high thresholds and their contribution to aroma and flavor is obviously less important. Therefore, it should be possible to lower their concentrations by selective methods and make this beverage more stomach friendly, increase its physiological wholesomeness without changing its attractive aroma and flavor. 

Another class of lipid components formed by heating which contribute to meat flavor is the lactones, which are formed by the lac-tonization of y- and 6-hydroxy fatty acids. 6-Long chain (6-tetra-decalactone) lactones predominate. Lactones can also be formed by conversion of low molecular weight saturated fatty acids, aldehydes and alcohols during heating of meat fat (13). Larick et al. (14) found Cla-Ci, 6-lactones associated with more desirable flavor of beef... 

The volatiles from cooked meat contain large numbers of aliphatic compounds including aldehydes, alcohols, ketones, hydrocarbons and acids. These are derived from lipids by thermal degradation and oxidation (J7) and many may contribute to desirable flavor. In addition, the aldehydes, unsaturated alcohols and ketones produced in these reactions, as well as the parent unsaturated fatty acids, are reactive species and under cooking conditions could be expected to interact with intermediates of the Maillard reaction to produce other flavor compounds. 

Milk is characterized as having a pleasing, slightly sweet taste with no unpleasant after-taste (Bassette et al., 1986). However, its bland taste makes it susceptible to a variety of flavor defects. Autoxidation of unsaturated fatty acids gives rise to unstable hydroperoxides, which decompose to a wide range of carbonyl products, many of which can contribute to off-flavors in dairy products. The principal decomposition products of hydroperoxides are saturated and unsaturated aldehydes (Frankel et al., 1961), with lesser amounts of unsaturated ketones (Stark and Forss, 1962), saturated and unsaturated hydrocarabons (Forss et al., 1961), semialdehydes (Frankel et al., 1961) and saturated and unsaturated alcohols (Hoffman, 1962 Stark and Forss, 1966). 

Lipid-derived volatile compounds play an important role in the flavor of foods. These compounds contribute to the characteristic notes of many dairy flavors, but are also responsible for many off-flavors. Parliament and McGorrin (2000) reviewed those volatile compounds important in milk, cream, butter, cultured creams and cheese. The pathways involved in the degradation of milk fat have also been reviewed by McSweeney and Sousa (2000) and compounds include FFAs, methyl ketones, lactones, esters, aldehydes, primary and secondary alcohols, hydroxyacids, hydroperoxides and ketoacids. 

---