Ethyl acetate flavour

Verghese, J. and Joy, M.T. (1 989) Isolation of the colouring matter from dried turmeric (Curcuma longa L.) with ethyl acetate. Flavour and Fragrance journal 4, 31-32. 

The model tests were carried out both iso-thermally (i.e. at constant temperature) and in temperature gradients (from warm to cold). Alcohols (e.g. ethanol, hexanol, octa-nol, decanol), aldehydes (e.g. decanal), ketones (e.g. diacetyl), acids (e.g. caproic acid), esters (e.g. ethyl acetate), terpenes (e.g. menthol, menthone, 6-pinene, limonene), amines (e.g. butyl amine), pyrazines and other classes of substances have been investigated as flavouring substances [6,9,11,13-18]. Fig. 5.6 shows the forma-... 

The quantity of bound flavouring substance also depends on the chain length of the fatty acids in the triglyceride, and on the presence of saturated or unsaturated fatty acids in it. Triglycerides with long chain fatty acids bind less ethanol and ethyl acetate than those with short chain fatty acids [6]. Triolein - a triglyceride that only contains the unsaturated oleic acid - binds more flavour than tripalmitin and trilaurin (both of which contain only saturated fatty acids) [6]. 

Permitted solvents for flavourings are diethyl ether, ethyl acetate, ethyl alcohol, glycerol, isopropyl alcohol, propylene glycol and water. Flavourings may also be used as emulsions prepared with permitted emulsifiers. 

Natural fruit aromas are mixtures of certain organic compounds and esters. Synthetic aromas prepared in laboratories are simple mixtures of these same esters and organic compounds. They are used in perfumes, foods and drinks to give taste and pleasant smells. Ethyl acetate, for example, is a colorless liquid with an apple flavour it is known as apple ester and is used in perfumery as a fruit essence. Propyl acetate has the smell of pears, isopentyl acetate that of bananas and ethyl butyrate smells of pineapples. All are colorless liquids. Higher molar mass esters are odorless. 

Although autolysis occurs fairly readily when yeast is stored (and consequently is of importance in influencing beer flavour (see Chapters 16 and 17), the process used to make extracts is accelerated by raising the temperature to 45 C (113°F) in the presence of small amounts of ethyl acetate or chloroform, and often in the presence of zinc salts. After a period of 6-12 hr, the autolysed (self digested) yeast is clarified and concentrated. The autolytic procedure involves the disintegration of the vacuole and the release of lytic enzymes (see Chapter 16). During the process the yeast cells are killed. 

In a further trial 46 ales (OG 1030-1050) from 5 brewing companies were examined by sensory profile analysis and by instrumental analysis [54]. The most important variables in the discriminant analysis were (/) iso-amyl alcohol content (instrumental), (ii) caprylic flavour (sensory), (Hi) sodium content (instrumental), (iv) meaty aroma (sensory), (v) ethyl acetate content... 

Another approach has been limited to the correlation of the headspace volatiles with flavour characteristics [30, 58]. Of the substances distinguished on the gas chromatograms the levels of the isoamyl alcohols, ethyl acetate, isoamyl acetate, and isobutanol have been shown to be important in the discriminant analyses discussed above. p-Phenylethanol and ethyl caprylate are not sufficiently volatile to be included in headspace analyses [39]. In this method [30, 58] the peak areas on the chromatograms were expressed as the percentage of the total peak area (excluding ethanol and the internal standard xylene). A chronologically updated data base was used to calculate... 

Our results showed that the flavour profile of peas was affected by market class, cultivar location, and crop year. The highest total volatile compound (TVC) was observed in cultivars from marrowfat-market class. Crops grown in Meath Park location had the highest TVC. Furthermore, different volatile compounds were identified in pea cultivars. In both crop years, cultivars from the green-market class had the highest mean values of esters and hydrocarbons, whereas the highest value of alcohols was observed for the marrowfat-market class, and the dun-market class had the highest mean values of ketones and pyrazine. 3-Methyl-butanol, 1-propanol, 2-ethyl-hexanol, 3-methyl-butanal, trichloromethane, 2-butanone, dimethyl sulfide, ethyl acetate and 2,3-diethyl-5-methyl pyrazine were the most abundant volatile compounds observed in the pea cultivars. 

Strawberries have been treated with 0.25-1.0% O2 or with 20% CO2 in air at 0 or 5°C for 10 days without detrimental effects on quality. However, off-flavour was found in strawberries kept in 0 or 0.25% O2 it was correlated with the concentrations of ethanol, ethyl acetate and acetaldehyde in the juice (Ke et al. 1991). 

For example, acetyl-CoA produces ethyl acetate by ethanolysis. In disrupted plant tissues, for example during production of juices, esters are rapidly broken down by various hydrolases, which results in a change of the flavour character. Also, many esters of aromatic acids are components of the aroma of fruits and spices. 

Important aroma compounds of black currant berries have been identified mainly by GC-O techniques by Latrasse et al. [119], Mikkelsen and Poll [115] and Varming et al. [7] and those of black currant nectar and juice by Iversen et al. [113]. The most important volatile compounds for black currant berry and juice aroma include esters such as 2-methylbutyl acetate, methyl butanoate, ethyl butanoate and ethyl hexanoate with fruity and sweet notes, nonanal, /I-damascenone and several monoterpenes (a-pinene, 1,8-cineole, linalool, ter-pinen-4-ol and a-terpineol) as well as aliphatic ketones (e.g. l-octen-3-one) and sulfur compounds such as 4-methoxy-2-methyl-butanethiol (Table 7.3, Figs. 7.3, 7.4, 7.6). 4-Methoxy-2-methylbutanethiol has a characteristic catty note and is very important to blackcurrant flavour [119]. 

The kiwi fruit is a cultivar group of the species Actinidia deliciosa. More than 80 compounds have been identified in fresh and processed kiwi [137]. Methyl acetate, methyl butanoate, ethyl butanoate, methyl hexanoate and ( )-2-hexenal have the most prominent effect on consumer acceptability of kiwi fruit flavour [137-140]. The volatile composition of kiwi fruit is very sensitive to ripeness, maturity and storage period [138, 139]. Bartley and Schwede [140] found that ( )-2-hexenal was the major aroma compound in mature kiwi fruits, but on further ripening ethyl butanoate began to dominate. Ripe fruits had sweet and fruity flavours, which were attributed to butanoate esters, while unripe fruits had a green grassy note due to ( )-2-hexenal [140]. The most important character-impact compounds of kiwi fruits are summarised in Table 7.4. 

The flavour of distillates from apple and pear is characterised by typical aroma compounds from these fruits formed by enzymatic degradation of fatty acids to C6-fragments like hexanol, trans-2-hexenol, as well as ethyl esters and acetates of hexanoic acid. In distillates of pears, especially of the variety Bartlett pear, the characteristic pear flavour is mainly dominated by the ethyl and methyl esters of frans-2-czs-4-decadienoic acid and trans-2-trans-A-decadienoic acid [27-29], The biogenesis of these monounsaturated, diunsaturated, and triunsaturated esters may be explained by -oxidation of unsaturated linoleic and linolenic acid in the fruits. The sesquiterpene compound a-farnesene, which is formed during postharvest ripening and storage of Bartlett pears [28], shows that quality and intensity of distilled pear spirits is mainly influenced by the quality and degree of ripeness of the fruits. 

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