Butter heptenal

Badings, H. T. 1965. The flavour of fresh butter and of butter with cold-storage defects in relation to the presence of 4-cis-heptenal. Neth. Milk Dairy J. 19, 69-72. 

Begeman, P. H. and Koster, J. C. 1964. Components of butterfat 4-cis-heptenal A cream-flavoured component of butter. Nature 202, 552-553. 

Creamy flavors in butter have been associated with 4-cis heptenal produced for autoxidation of isolinoleic acid (Begeman and Koster, 1964). Drier flavor in foam spray-dried milk has been associated with 6-rra x-nonenal, which has a flavor threshold in fresh milk of 0.07 pg/kg (Parks et al., 1969). Bassette and Keeney (1960) implicated a homologous series of autoxidation-derived saturated aldehydes, together with products of Maillard browning, in cereal-type off-flavors in powdered skim milk. Staleness in dry whole milk may be associated with saturated and unsaturated aldehydes (Parks and Patton, 1961). 2,4-Decadienal has been reported to be the principal compound responsible for the off-flavor associated with spontaneously oxidized milk (Parks et al., 1963). Oxidized flavors in sunlight-exposed milk are commonly related to C6 to Cn alk-2-enals... 

Occurrence E)-2-A. Cg-C,3 in citrus oils, especially bitter orange, Cg also in guava and ginger aromas, C, in bread, cucumber, carrot (see vegetable flavors) and rice flavor, c,o in coriander oil, butter, chicken and guava aroma, C,2 in coriander oil, peanut and meat flavor. (Z)-4-Heptenal is found, among others, in "butter, seafood and tea flavor, (Z)-3- and (Z)-6-nonenal in cucumber, melon and fish aroma, and (Z)-4-decenal in calamus oil and Citrus junos oil. ... 

At a level of 1 ppb (767) (Z)-4-heptenal (5) confers a creamy flavor 220) to deodorized butter oil. At higher concentrations (from 2 ppm) this aldehyde causes rancidity in butter (22) and soybean oil 560). 

Haverkamp-Begemann, P., and J. C. Koster 4-c/5-Heptenal A Creamy-Flavored Component of Butter. Nature 202, 552 (1964). 

Z)-4-heptenal), which occurs in beef and mutton and often in butter (odor threshold in Table 3.32). Also, the processing of oil and fat can provide an altered fatty acid profile. These can then provide new precursors for a new set of carbonyls. For example, (E)-6-nonenal, the precursor of which is octadeca-(Z,E)-9,15-dienoic acid, is a product of the partial hydrogenation of linolenic acid. This aldehyde can be formed during storage of partially hardened soya and linseed oils. The aldehyde, together with other compounds, is responsible for an off-flavor denoted as hardened flavor . Several reaction mechanisms have been suggested to explain the formation of volatile carbonyl compounds. The most probable mechanism is the P-scission of monohydroperoxides with formation of an intermediary short-lived alkoxy radical (Fig. 3.26). Such P-scission is catalyzed by heavy metal ions or heme(in) compounds (cf. 3.7.2. L7). 

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