Biochemical changes to milk following treatment by a novel, cold atmospheric plasma system

It has previously been shown that non-thermal (i.e., cold) plasma can successfully decontaminate milk from Escherichia coli. This study investigated the possible biochemical changes to the protein, free fatty acids and volatiles profiles of whole raw milk samples following application of cold plasma. Raw milk was treated with a cold plasma system at intervals of 0, 3, 6, 9, 12, 15 and 20 min. Significant changes were observed for 1 octanol (P < 0.05), 2 heptanone (P < 0.01), 2 hexenal (P < 0.01), 2 octenal (P < 0.05), nonanal and benzaldehyde (P < 0.001). Plasma treatment did not result in significant changes to the lipid composition of raw milk. However, exposure to cold plasma significantly increased the total aldehyde content following 20 min treatment. No significant difference was observed in the total ketone or alcohol levels.