Effect of oxidation state on volatile compounds in yak beef liver storage at low temperature

In order to investigate effects of oxidation state on volatile compounds of yak liver storage at low temperature, the peroxide value ( POV) , thiobarbituric acid reactive substances ( TBARS) and volatile compounds of beef liver from adult yak were determined pre-and post-storage at low temperature with the presence of oxygen. It indicated that TBARS and POV increased by 135.96% and 197.28% through storage, respectively. There were 31 volatile compounds in beef liver with 10 volatile compounds only detected poststorage, such as hyacinthin, E-2-decenal and 2-heptanone. The aldehydes increased by 17.38%, and 3straight aliphatic aldehydes hexanal, heptanal and octanal increased by 8.95%, 3.42% and 1.17%, respectively, with isovaleraldehyde decreased by 1.58%. Ketones decreased by 10.40% with increasing methylketones such as 2-butanone and 2-heptanone, while acetone decreased by 12.45%. There was no significant difference on heterocycles between pre-and post-storage with decreasing benzothiazole reduced by 1.71% significantly (p<0.01) . It showed that the increasing oxidation state could increase lipid oxidation products such as straight aliphatic aldehydes and methylketones, and decrease Maillard reaction products such as isovaleraldehyde and benzothiazole.