Study On Key Aroma Compounds And Perceptual Interaction Among Odorants In Soy Sauce Aroma Type Xi Baijiu

This paper made a qualitative and quantitative analysis of the aroma compounds,the key aroma compounds and sensory attributes were identified and sensory interaction among odorants were investigated in three soy sauce aroma type Xi baijiu.The main research contents and conclusions were as follows:(1)The volatile compounds were identified by headspace solid-phase microextraction(HS-SPME)and liquid-liquid extraction(LLE)combined with gas chromatography-olfactometry(GC-O),gas chromatography-mass spectrometry(GC-MS),gas chromatography-flame photometric detection(GC-FPD)and gas chromatography-nitrogen phosphorus detector(GC-NPD)in soy sauce aroma type Xi baijiu.The result indicated that a total of 103 odorants were determined by LLE,moreover,the 63 aroma compounds were selected by aroma intensity(AIs)and 40 key aroma compounds were further screened out according to quantification and the calculation of odor activity values(OAVs).However,a total of 93 compounds were identified by HS-SPME,65 aroma compounds were selected by AIs and 35 key aroma compounds were screened out by OAVs.(2)Sensory attributes of three soy sauce aroma type Xi baijiu were studied by quantitative descriptive sensory analysis.The results showed that the Xi baijiu aroma profile could be described by fruity,sweet,sauce,acid,floral,alcoholic,caramel,roasted and sulfuric.Moreover,sauce,sweet,alcoholic and sulfuric attributes of Xijiuyinxiangguizhou baijiu were the strongest,the acid,roasted and fruity attributes of Xijiulan baijiu were the strongest,and the caramel aroma attribute of Xijiuyinzhi baijiu was the strongest.Furthermore,the heatmap analysis well reflected the significant difference of key aroma compounds among three baijiu samples.It was proved that 40 key aroma compounds were the key aroma compounds of Xi baijiu by the recombination experiment.The correlation among 40 key aroma compounds,seven sensory attributes,three Xi baijiu samples and corresponding recombination solutions were evaluated through partial least-squares regression(PLSR)analysis.(3)The odor thresholds of 16 sulfur compounds,8 key esters and 106 binary mixtures were detected by a three-alternative forced-choice(3-AFC)procedure.The perceptual interaction of sulfur compounds and esters were investigated by S-curve method and OAV method.The results showed that 52 binary mixtures showed mask effect.39 binary mixtures were identified as additive effect and 15 binary mixtures were synergistic effect by S-curve method.The additive effect of 33 binary mixtures and the synergistic effect of 21 binary mixtures were identified by OAV method.Among them,the perceptual interactions of dimethyl disulfide with ethyl acetate,ethyl propanoate,ethyl butanoate,ethyl isovalerate,ethyl hexanoate and ethyl octanoate showed mask effect.Dimethyl trisulfide showed additive or synergistic with propyl acetate,ethyl propanoate,ethyl isovalerate,ethyl hexanoate,ethyl octanoate and ethyl phenylacetate.3-Mercaptohexyl acetate and 3-mercapto-1-hexanol mostly showed synergistic and additive effects with esters.