Esters flavor development

A good example of potentially useful enhanced oxidation is in the aging of fermented products such as spirits where limited oxidation is potentially useful for flavor development and early maturation of the product. Sonication has been successfully employed to enhance the flavor of some wines and spirits. The effect of irradiation with 1 MHz ultrasound has been shown to alter the alcohol/ester balance in such products to give the appearance of an aged product [8], This seems to be particularly successful for whisky where a patented method has been described which reduces the normally prolonged aging time to less than 1 year by applying ultrasound to the liquor in a standard barrel [9],... 

Whisk(e)y flavor. The typical W. flavor develops on maturation in charred (toasted) wooden barrels (Bourbon) or old sherry barrels (Scotch). Components relevant for the sensory impression are the fusel alcohols (ca. 2000-4000 ppm) and their acetates, ethyl acetate (see fruit esters), and the ethyl esters of saturated and unsaturated fatty acids, acetaldehyde, 3-methylbutanal... 

Do et al. [74] investigated flavor development in peaches as influenced by harvest maturity and artificial ripening. Peaches obtain most of their characteristic flavor from lactones, and of course, these lactones increase as stage of maturity advances. Artificial ripening of the peaches does not result in similar levels of lactones in the ripe fruit. Artificially ripened peaches contained only about 20% of the total lactone content of tree ripened peaches. Benzaldehyde and total esters in the artificially ripened peaches reached only 20% and 50% of their respective concentrations found in tree-ripened fruit. 

Ghlorpropham. (3-Chlorophenyl)carbamic acid 1-methyl ester [101-21-3] (Chlorpropham, CJPC) (21) was patended in the early 1950s and is a carbamate. Its only use in the United States is on stored Irish potatoes to inhibit bud development. The potatoes, which are generally stored at temperatures >10° C for maximum flavor, are treated by passing a stream of air laced with chloropropham over the potatoes for 48 hours after which the potatoes are purged with pure air. 

Alitame (trade name Adame) is a water-soluble, crystalline powder of high sweetness potency (2000X, 10% sucrose solution sweetness equivalence). The sweet taste is clean, and the time—intensity profile is similar to that of aspartame. Because it is a stericaHy hindered amide rather than an ester, ahtame is expected to be more stable than aspartame. At pH 2 to 4, the half-life of aUtame in solution is reported to be twice that of aspartame. The main decomposition pathways (Fig. 6) include conversion to the unsweet P-aspartic isomer (17) and hydrolysis to aspartic acid and alanine amide (96). No cyclization to diketopiperazine or hydrolysis of the alanine amide bond has been reported. AUtame-sweetened beverages, particularly colas, that have a pH below 4.0 can develop an off-flavor which can be avoided or minimized by the addition of edetic acid (EDTA) [60-00-4] (97). 

Since the acetal exists in equiUbtium with the aldehyde, it is possible for the aldehyde to be released when water is added in a mixed drink, changing the balance and giving a burst of freshness to a mixed drink. Ethyl esters of terpene alcohols in citms oils and other botanicals, plus the ethyl esters of fatty and volatile acids, are formed during prolonged exposure to ethyl alcohol. Certain beverage alcohol products that need to contain milk, eggs, or other protein containing materials must be developed carefully and the added flavors must be considered to prevent the precipitation of the protein and separation of the product. 

Uses. Cinnamyl alcohol and its esters, especially cinnamyl acetate, are widely employed in perfumery because of their excellent sensory and fixative properties. They are frequently used in blossom compositions such as lilac, jasmine, lily of the valley, hyacinth, and gardenia to impart balsamic and oriental notes to the fragrance. In addition, they ate utilized as modifiers in berry, nut, and spice flavor systems. The value of cinnamyl alcohol has also been mentioned in a variety of appHcations which include the production of photosensitive polymers (49), the creation of inks for multicolor printing (50), the formulation of animal repellent compositions (51), and the development of effective insect attractants (52). 

Paprika contains capsombin and capsanthin (Fig. 8.3) which occur mainly as the lauric acid esters, and about 20 other carotenoid pigments. Paprika is produced in many countries which have developed their own specialties. Cayenne or cayenne pepper, produced from a different cultivar of C. annum, is usually more pungent. C. frutescens is the source of the very pungent Tabasco sauce. Paprika oleoresin is produced by solvent extraction of the ground powder. Obviously paprika supplies both flavor and color and its use is limited to those products compatible with the flavor. The recent rise in demand for tomato products in the form of pizza, salsa, etc., has increased the demand for paprika. Paprika is used in meat products, soups, sauces, salad dressings, processed cheese, snacks, confectionery and baked goods.1018... 

Uses Manufacture of esters for use in perfumes, flavors, soaps, lotions, ointments photographic developer for color movie films dying nylon filament, textiles, and sheet plastics solvent for dyestuffs, cellulose, esters, casein, waxes, etc. heat-sealing polyethylene films bacteriostat, insect repellant emulsions ballpoint pen inks and stencil inks surfactant. 

However, the lower fatty acid esters (particularly the acetates) of the acyclic terpene alcohols geraniol, linalool, and citronellol are extremely important both as fragrance and as flavor substances. The acetates occur in many essential oils, sometimes in rather high amounts. Formates, propionates, and butyrates occur less frequently. As a result of the development of large-scale production processes for terpenes, the esters of acyclic terpene alcohols are nearly always made synthetically. All acyclic terpene esters that are used as fragrance and flavor materials can be prepared by direct esterification of the appropriate alcohols. However, special precautions are required for the esterification of linalool. 

Quality standards for some flavor constituents will eventually be developed—linalool for muscats, for example, and perhaps phenethanol for certain types of wine. Kahn and Conner (124) have published a rapid GLC method for phenethanol. It has been suggested (60) that detection of bacterial activity from the presence and amount of minor bacterial byproducts (arabitol, erythritol, and mannitol) may be useful. Based on GLC determination of carbonyls, esters, and higher alcohols, beers were accurately classified into three categories (125). Anthocyanin content has been determined quantitatively by using molar absorbance values for five anthocyanin pigments (126). 

Basic Protocols 8 and 9 look at specific groups of compounds, aldehydes and esters, which are of more interest to flavor houses and research scientists. For flavorists, the strength of citms flavor is determined from the aldehyde content, while the fruity aroma is attributed to the ester content. Over the years, these procedures have been modified. Basic Protocol 8 is a titration method to determine aldehyde content in citms oils. It was originally developed for lemon oil however, it is also applicable to other citms oils. Alternate Protocols 4 and 5 also produce similar results. Alternate Protocol 4 is based on... 

Most enologists prefer the cooler temperatures and slower fermentation to develop more flavor and bouquet. Yeast at lower temperatures produces more esters and other aromatic constituents. 

Natural food flavors such as terpenes, hydrocarbons, alcohols, aldehydes, ketones, esters, acids, lactones, amines, sulfur compounds are enzymatically produced in fruits and vegetables. On the contrary, processed food develops its characteristic acceptable flavors from chemical reactions within its components at temperatures far below those at which its major components, i.e., lipids, proteins and carbohydrates pyrolyze. 

Food, flavors consist of numerous compounds, none of which alone is characteristic of specific food. Classes of compounds which emcompass food flavors are - hydrocarbons (aliphatic, ali-cyclic, aromatic) carbonyls (aldehydes, ketones) carboxylic acids, esters, imides, anhydrides alcohols, phenols, ethers alkylamines, alkylimines aliphatic sulfur compounds (thiols, mono-, di- and tri-sulfides) nitrogen heterocyclics (pyrroles, pyrazines, pyridines) sulfur heterocylics (thiophenes, thiazoles, trithiolane, thialidine) and oxygen-heterocyclics (lactone, pyrone, furan). Discussion will be limited to striking developments in heterocyclics. 

The non-aqueous lipase system for flavor esters developed by our group used components and preparative techniques for enzyme immobilization, that would not only be cost effective and simple but also meet regulatory requirements. The enzyme could have been immobilized by a number of methods however for the Intended application only (i) adsorption (11) ionic bonding or (lii) glutaraldehyde cross-linking would be... 

The major advantage of the seunpling technique developed, was that some trace chemicals could be trapped tind described for the first time as Black Truffle aroma constituents. In particular, some compounds, important flavor contributors, generally appearing in small concentrations, such as benzaldehyde, propanal, ethyl acetate, anisole or dimethyl disulfide - previously identified in Shiitake mushrooms (9) - could be characterized. This was also the case for three aromatic compounds, toluene, xylene and ethyl benzene, well known as raw vegetable constituents (1 ). In addition, two aliphatic esters, isopropyl and sec-butyl formates, and one cyclic sulfur compound (2-formyl thiophene) previously reported respectively in plums and apples (W) and in coffee and bread products (n) were identified. 

Butter Flavors. Technologies for the hydrolysis of butter fat to produce and concentrate the free fatty acids to enhance the butter flavor of products have been available for decades. More recently, biotechnologists have developed methods for producing a variety of fairly pure enzymes, economically and in large quantities. The increased availability of lipases (glycerol ester hydrolases) from microbial... 

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