The Neutral Carbonyl Compounds in Blue-Mold Type Cheese

Abstract

A simple procedure is described for the detection of the various methyl ketones in blue-mold type cheese which entails vacuum distillation of relatively small samples and paper chromatographic separation of the mixed 2,4-dinitrophenylhydrazone derivatives formed in the distillates. Application of the method in the examination of 10 different samples of cheese, including French Roquefort, Danish and Domestic Blue, and Gorgonzola, revealed that acetaldehyde, acetone, butanone-2, pentanone-2, heptanone-2, nonanone-2, and undecanone-2 may be present in this type of cheese. A single sample possessing little or no desirable aroma contained no heptanone-2 or nonanone-2. These, as well as pentanone-2 and acetone, were always present in cheeses possessing a typical aroma. Only traces of undecanone-2 were detected in two samples. © 1956, American Dairy Science Association. All rights reserved.