Twenty‐five years of flavor research in a food industry

Abstract

AND SUMMARYIn the last few decades, flavor research has developed along different main routes. The first step was the discovery of the complex mixtures of volatile components that together build the particular flavors. Apart from this, interest became focused on the taste substances which, through interaction with the flavor carriers, impart aroma to a food. The third main route was the investigation of the deterioration in odor and taste due to oxidative or microbial spoilage. As these investigations progressed, it became clear that these flavor areas show considerable interaction and that, in addition, other sensory impressions of a product as regards shape, texture, color, etc., play a role in the ultimate subjective perception by the consumer. In this way, flavor research has widened into a complex branch of science, and it is becoming more and more apparent that consumer testing that encompasses all the elements mentioned above will have to indicate the real preferences of the public.

Oxidative pathways to the formation of off-flavours

“…For example, partial hydrogenation of linolenate in soyabean oil produces isomeric dienes, known as isolinoleic acids. Keppler andcoworkers (1965, 1967) demonstrated that cis,cis-9,15 and 8,15-octadecadienoates are the precursors of an unpleasant 'hardening' flavour that develops during storage of hydrogenated oils. The aldehyde 6-trans-nonenal has been reported to be responsible for this off-flavour (Table 6.3).…”

Mikrobielle Produktion von Aromastoffen unter besonderer Berücksichtigung von Fruchtnoten

“…So basiert z. B. die von KEPPLER [34] beschriebene Lactonproduktion auf der Flhigkeit von Saccharomyces cerevisiae, diese aus Ketosauren zu synthetisieren. Die Bildung von Ethylacetat durch Candida utilis wird bei Ethanolzugabe beschleunigt [6].…”

The quantification of carbonyl compounds in oxidized fat by gas chromatography of the trichlorophenylhydrazones

“…Several classes of compounds have been implicated in off-flavor development of deteriorating oils. Flavor descriptions and thresholds were studied for many of these (Evans et al, 1974;Badings, 1960;Keppler, 1977;Selke et al, 1975). Duin (1960) identified the following classes of carbonyls as contributing to offflavor in butter; saturated aldehydes (C^ -C^g), 2-enals (C^ ~^ll^ ' 2,4-dienals (C^ -C^^^), enals with the double bond not in the 2-position (Cg -C^g), and dienals with a double bond in non-conjugated position to the 2-enal configuration (Cg -C^g).…”

“…By mixing 2-ketones at subthreshold levels, a synergistic effect was reported, and thresholds of individual compounds reduced. Keppler (1977) reported threshold values for a number of aldehydes. Values included 0.04 ppm for 2-trans-4-trans-hexadienal, 0.50 ppm for 2-trans-4-trans-heptadienal, and 0.35 ppm for 2-trans-pentenal.…”

“…Values included 0.04 ppm for 2-trans-4-trans-hexadienal, 0.50 ppm for 2-trans-4-trans-heptadienal, and 0.35 ppm for 2-trans-pentenal. The interaction between the aldehydes also played a part which decreased or Increased the flavor strength (Keppler, 1977).…”