低温储藏条件下氧化状态对牦牛肝中挥发性化合物的影响

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

为了研究低温储藏条件下氧化状态对牦牛肝中挥发性化合物的影响,选取成年牦牛肝为研究对象,在低温条件下进行储藏,测定储藏前后的过氧化氢值(POV)、硫代苯巴比妥酸反应底物值(TBARS)以及挥发性化合物。结果表明,相比于储藏前,储藏后的POV和TBARS分别增加了135.96%和197.28%。储藏前后共检出31种挥发性化合物,其中苯乙醛、反-2-癸烯醛、2-庚酮等10种物质仅在储藏后检出。经储藏后,醛类物质含量增加了17.38%,其中己醛、庚醛、辛醛3种直链脂肪醛分别增加了8.95%、3.42%、1.17%,而异戊醛减少了1.58%。经过储藏酮类减少了10.40%,丙酮下降了12.45%,而2-丁酮、2-庚酮等甲基酮含量均提高。杂环类化合物在储藏前后差异不显著,但苯并噻唑却极显著地降低了1.71%(p<0.01)。结果表明,在低温储藏条件下氧化程度的升高,增加了直链脂肪醛和甲基酮等脂质氧化产物,而减少了异戊醛、苯并噻唑等美拉德反应产物。

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 post- storage,such as hyacinthin,E-2-decenal and 2-heptanone. The aldehydes increased by 17.38% ,and 3 straight 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 Mairlard reaction products such as isovaleraldehyde and benzothiazole.