Abstract: In order to investigate the changes of flavor substances in whole-fat cow and goat milk powder during storage, the volatile compounds of whole-fat cow and goat milk powder during accelerated oxidation were analyzed using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPEM-GC-MS). The results indicated that 56 and 63 volatile substances were identified in whole-fat cow and goat milk powder, respectively, mainly including acids, alcohols, carbonyls, esters, aromatics and heterocyclic compounds. Ten significantly differential volatile compounds were identified between whole-fat cow and goat milk powder by principal component analysis (PCA) and cluster analysis (CA). The relative content of butyric acid decreased and the relative content of 2-nonanone and 1-chloropentane increased in whole-fat cow milk powder during accelerated storage. The relative contents of nonanaldehyde, octanoic acid, propionic acid, and butylhydroxytoluene decreased, and the relative contents of benzaldehyde, 2-heptanone, and allyl n-propyl ester increased in whole-fat goat milk powder.

Key words: whole-fat cow milk powder; whole-fat goat milk powder; headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry; volatile compounds