Abstract: 【Objective】The effect of a moderate addition of oxidation sheep bone oil on the volatile flavor compounds in thermal reactive mutton flavor seasoning were investigated in order to provide a scientific basis for improving the flavor of the high quality mutton flavor seasoning.【Method】Samples of oxidized sheep bone oil indicating peroxide value, acid value and p-anisidine value were prepared by the control oxidization technology. Influences of sheep bone oil on the volatile flavor compounds in thermal reactive mutton flavor seasoning were discussed. An electronic nose was used to analyze the three thermal reactive mutton flavor seasoning, including without adding sheep bone oil, adding non-oxidized sheep bone oil and adding moderate oxidized sheep bone oil. With the discrimination index of the PCA about the three mutton flavor seasonings as response value, the effects of sheep bone oil on mutton flavor seasonings were studied. The volatile flavor compounds in three systems were analyzed by solid phase micro-extraction (SPME) combined with gas chromatography mass spectrometry (GC-MS), and a parameter named “relative odor activity value (ROAV)”was applied in evaluating the contributions to global odor perception of three systems. The characteristic volatile flavor compounds of mutton flavor seasoning added with oxidized sheep bone oil were identified by cluster analysis (CA) method.【Result】The electronic nose responded differently to the flavor of different mutton flavor seasonings. The discrimination index of adding non-oxidized sheep bone oil and without adding sheep bone oil was 0.589. The discrimination index of adding oxidized sheep bone oil and without adding sheep bone oil was 0.917. The discrimination index of adding non-oxidized sheep bone oil and adding oxidized sheep bone oil was 0.787. A total of 42, 63 and 61 kinds of volatile flavor compounds were identified in the three thermal reactive mutton flavor seasonings, including without adding sheep bone oil, adding non-oxidized sheep bone oil and adding moderate oxidized sheep bone oil. Among these compounds, the predominant ones were aldehydes and hydrocarbons. The relative contents of S, N-containing heterocyclic compounds were not significantly different. Adding sheep bone oil resulted in a significant decrease in hydrocarbons relative contents but a significant increase in aldehydes. CA showed that octanal, nonanal, capraldehyde, (E, E)-2,4-decadienal, tetradecanal, heptaldehyde, (E)-2-nonenal, dodecanal, 1-octen-3-ol, heptanol, (E, E)-2,4- nonadienal were the key volatile flavor compounds of the mutton flavor seasonings. It could be known that the key volatile flavor compounds have more fat ordor with less sweet/green, burnt, and citrus smell. The 11 key volatile flavor compounds could be classified into 3 clusters. After adding oxidized sheep bone oil, the relative odor activity value of (E, E)-2,4-decadienal and (E)-2-nonenal increased, on the contrary, the relative odor activity value of capraldehyde decreased. The relative odor activity value of (E, E)-2,4-decadienal, (E)-2-nonenal and capraldehyde were not significantly different between adding non-oxidized sheep bone oil and without adding sheep bone oil.【Conclusion】After adding oxidized sheep bone oil, the kinds of the volatile flavor compounds were increased, (E, E)-2,4-decadienal and (E)-2-nonenal were the important characteristic volatile flavor compounds for improving the mutton flavor seasoning.

Key words: sheep bone oil , oxidation , mutton flavor seasoning , volatile flavor compounds