Studies on Oxidized Milk Fat. III. Chemical and Organoleptic Properties of Volatile Material Obtained by Fractionation with Various Solvents and Girard's Reagent

Abstract

Summary The predominant odor compounds from the oxidized milk fat used in this study were ketones. None of these ketones were methyl ketones and a large proportion of them were unsaturated. Presumptive evidence has been presented which suggests that lactones are to be found in the volatile material and these have been correlated with the fruity and coconut odor of certain fractions of the distillate. The flavor of oxidized milk was closely simulated when the ketone fraction and non-carbonyl neutral fraction were mixed in milk in the proper proportions. It has been shown that in the advanced stages of milk fat oxidation it is possible to isolate flavor fractions which are typical of earlier stages in the oxidation and that the change in organoleptic character of milk fat during oxidation is due to a blending of different flavor compounds. The prolonged distillation of oxidized milk fat resulted in the formation of an α , β -unsaturated carbonyl compound of the formula C 10 H 18 O and the properties of its 2,4-dinitrophenylhydrazone have been presented.