Study On Aroma Characteristics And Synergistic Mechanism Of Traditional Huangjiu

Traditional Huangjiu is popular among consumers for its flavor characteristics of "color clear,fragrant,sweet,and mellow" made by its unique brewing process.But it also caused the problem of poor batch stability and even flavor defects due to its natural fermentation mode in an open environment.In order to produce traditional Huangjiu with high flavor and quality,it is necessary to reveal the flavor characteristics of traditional Huangjiu in combination with modern scientific methods on the basis of inheriting traditional brewing technology in order to optimize the brewing conditions.This study reveals the flavor characteristics of traditional Huangjiu in Shaoxing by identifying the key aroma components and potential sensory interactions of traditional Huangjiu in Shaoxing,and determining the influencing factors of its flavor characteristics,as a theoretical basis for flavor regulation to enhance the tradition of Shaoxing The flavor quality of Huangjiu can guide the flavor control of traditional Huangjiu in other regions.The main conclusions of the paper are as follows:(1)Firstly,33 kinds of aroma active compounds in traditional Huangjiu in Shaoxing were determined by HS-SPME combined with GC-MS,GC-FPD,GC-O and OAV.Based on the results of GC-O,the aroma reorganization model and omission model of traditional Huangjiu in Shaoxing were established.The key aroma compounds in traditional Huangjiu in Shaoxing were further screened,and the key aroma compounds in traditional Huangjiu in Shaoxing were finally identified as phenethyl alcohol,furfural,benzaldehyde,vanillin,acetic acid,acetophenone,ethyl acetate,ethyl propionate,Ethyl 2-methylbutyrate,isoamyl acetate,ethyl hexanoate,ethyl lactate,ethyl phenylacetate,γ-nonolactone and dimethyltrisulfide.The correlation between aroma active compounds and 8 sensory attributes of Huangjiu was analyzed by PLS-DA simulation.The ester aroma was positively correlated with hexanal,nonanal,furfural and benzaldehyde;the korean aroma was positively correlated with hexanoic acid;fruity The aroma was positively correlated with ethyl 2-methylbutyrate,phenylethanol,acetic acid,and furfural;the aroma was positively correlated with phenol and acetic acid;the caramel aroma was positively correlated with dimethyltrisulfide.(2)Exploring the synergy between key ester compounds and key aldol compounds through the S-curve method and σ-τ diagram method,combined with the effects of sensory attributes;5 groups of synergistic combinations were identified: ethyl lactate/ethyl acetate(90:10,m/m)mixture,ethyl phenylacetate/ethyl 2-methylbutyrate(93: 7,m/m)mixture,ethyl acetate/ethyl hexanoate(97:3,m/m)mixture and ethyl phenylacetate/ethyl propionate(89:11,m/m)mixture,benzaldehyde and furfural(71:29,m/m)mixture.In addition,vanillin and phenethyl alcohol have synergy with other compounds.When they exist at a certain ratio in the subthreshold concentration to the threshold concentration range,they can produce a synergy,thereby reducing the overall threshold of the system.Additive experiments verified the synergy between these substances.(3)On the basis of the determined synergistic ratio relationship,the flavor characteristics of traditional Huangjiu fermented by different fermentation materials,fermentation temperature and storage time were dynamically monitored by gas chromatography mass spectrometry and artificial sensory evaluation,and combined with data visualization technology,it was found that: At the fermentation temperature of glutinous rice and Jianhu water at the winter solstice,the compound content ratio is closest to the synergistic ratio.At the same time,the longer the storage time of the wine sample,the closer the compound content ratio is to the synergistic ratio.Therefore,it can be determined that the aroma quality of traditional Huangjiu,which uses glutinous rice and Jianhu water as raw materials,is put into production around the winter solstice and has a longer storage time.These results indicate that the closer the content ratio between key compounds is to the synergy ratio,the higher the quality of traditional Huangjiu.This result is also consistent with sensory evaluation.This conclusion establishes a theoretical basis for the regulation and control of the flavor of traditional Huangjiu from the perspective of influencing factors of traditional Huangjiu,and helps to improve the flavor quality of traditional Huangjiu.