Apple aroma

Stereoanalysis of 2-alkyl-branched acids, esters and alcohols in apple aroma concentrate... 

The statement that the aroma of apples is due to methyl butyrate is too simple. Life is more complex a number of chemical compounds contribute to apple aroma. However, methyl butyrate makes amajor contribution. If you were to smell this compound, you would recognize the aroma of apples. 

More than 350 volatile compounds have been identified in apples [44]. Only a few of these volatiles have been identified as being responsible for apple aroma [45]. The most abundant volatile components in apples are esters (78-92% of total volatiles), alcohols (6-16% of total volatiles), aldehydes, ketones and ethers [35, 45], which are present in various amounts in different cultivars [46]. Esters are the principal compounds responsible for apple odour (Table 7.1, Fig 7.1)... 

Ethyl 2-methylbutanoate, 2-methylbutyl acetate and hexyl acetate contribute most to the characteristic aroma of Fuji apples [49]. In Red Delicious apples, ethyl butanoate, ethyl 2-methylbutanoate, propyl 2-methylbutanoate and hexyl acetate contribute to the characteristic aroma as determined by Charm-Analysis and/or AEDA [50, 51]. In a comparative study of 40 apple cultivars, the highest odour potency or Charm value was found for -damascenone [52]. This compound usually occurs in a glycosidically bound form and is present primarily in processed products owing to hydrolysis of the glycoside bond after crushing fruit cells [53]. -Damascenone has a very low odour threshold with a sweet, fruity, perfumery odour and is not typical of apple aroma in gen-... 

Young, H., Rossiter, K., Wang, M., Miller, M. (1999) Characterization of Royal Gala apple aroma using electronic nose technology potential matirrity indicator. J. Agric. Food Chem. 47 5173-5177. 

An extensive list of volatile compounds in apples and other fruits was included in a review by Nursten (222). White (223) reported that the principal components of the aroma of apples were alcohols (92% ) methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-methyl-l-propa-nol, 2-methyl-l-butanol, and 1-hexanol. The other constituents included 6% carbonyl compounds and 2% esters. Later, MacGregor et al. (224) tentatively identified 30 volatile components of McIntosh apple juice including four aldehydes, one ketone, 11 alcohols, 10 esters, and four fatty acids. The major organic volatiles in several different extractants of Delicious apple essence were identified and quantitatively estimated by Schultz et al. (225). They reported from sensory tests that low molecular weight alcohols contributed little to apple aroma. Flath et al. (226) identified... 

Stereoanalysis of 2-alkyl-branched acids, esters and alcohols in apple aroma concentrate Restriction capillary (25 m X 0.23 mm i.d.) coupled to a glass capillary column, (25 m X 0.32 mm i.d.) coated with a 18.8% solution of PS-255 and 1.5% dicumyl peroxide. Glass capillary column (38 m X 0.23 mm i.d.) coated with heptakis (2,3,6-tri-0-ethyl)-/3-cyclodextrin (33% in OV-1701-vinyl) 6... 

Removal of various organic compounds form industrial effluent recovery of apple aroma... 

CH3COO(CH2)3CH3, C6H1202, Mr 116.16, bpm3kPa 126.5°C, d20 0.882, rag0 1.3942, is a liquid with a strong fruity odor. It occurs in many fruits and is a constituent of apple aromas. 

A electronic nose based on an array of eight quartz microbalance-based (QCM) sensors coated with modified MPPs (5,10,15,20-tetraphenylporphyrin) was used for apple aroma measurements [13], The response of each QCM sensor was modeled with Brunauer-Emmett-Teller (BET) adsorption isotherms. By means of multivariate analysis on all sensor responses, the different compounds could be discriminated well and quantified accurately. This calibration protocol can be used to characterize the sensors for the vapors of complex mixtures. 

Z. Xiaobo, Z. Jiewen, Comparative analyses of apple aroma by a tin-oxide gas sensor array device and GC/MS. Food Chem. 107, 120-128 (2008)... 

Dixon J, Hewett EW (2000) Factors affecting apple aroma/flavour volatile concentration a review. New Zeal J Crop Hort 28 155-173... 

Bacteria are not affected by sorbic acid, and, in fact, several species can metabolize the acid to eventually yield 2-ethoxyhexa-3,5-diene, a compound that imparts a distinctive geranium odor/tone to wines (Section 11.3.5). Other odor/flavor-active compounds detected in spoiled wines treated with sorbic acid include l-ethoxyhexa-2,4-diene and ethyl sorbate (Chisholm and Samuels, 1992), the latter of which has been associated with off-flavors in sparkling wines (De Rosa et al., 1983). Whereas Chisholm and Samuels (1992) described ethyl sorbate as possessing a honey or apple aroma, De Rosa et al. (1983) thought the compound imparted a very unpleasant pineapple-celery odor upon short-term (6 month) storage. Based on this observation, De Rosa et al. (1983) recommended that sorbates should not be used in sparkling wine production. 

A Plotto, MR McDaniel, JP Mattheis. Characterization of changes in Gala apple aroma during storage using Osme analysis, a gas chromatography-olfactometry technique. J Am Soc Hortic Sci 125 714-722, 2000. 

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