Research On Flavor Compounds Of Different Chinese Baijiu Based On Rapid Detection Technology

Baijiu is a traditional alcoholic beverage in China.The flavor of each Chinese Baijiu has its own similarities and differences.It is difficult to identify different Chinese Baijiu quickly and accurately.The distilled liquor can improve the quality of products significantly.However,the judgement of segmented Baijiu depends mainly on manual experience and accuracy.After aging,Baijiu will have more pure aroma and softer taste,and it is difficult to identify the aging time.In this study,different flavor types,liquor taking stages and aging time Chinese Baijiu were selected as the research objects.The different compounds in different Baijiu were studied by various analysis methods and omics analysis.The results are as follows:(1)UPLC-Q-TOF-MS is used to study the non-volatile components in different series of Chinese Baijiu,and the obtained mass spectrometry data is dimensionaly reduced by omics analysis technology.Different series of liquors are used in the main Component analysis(PCA)and Orthogonal Partial Least Square Discriminant Analysis(OPLS-DA)models are well distinguished.In the positive and negative ion mode,the PCA model extracts 3 principal components PC1,PC2,and PC3,respectively explaining The total variation of different liquors is 67.4% and 58.6%.The OPLS-DA model uses mass spectrometry data to extract the difference variables between different liquors,statistical methods was used to screen the difference variables,the liquid mass network database,UPLC-Q-TOF-MS primary and secondary mass spectrometry information are used to identify the substance structure.A total of13 different compounds were identified in the positive and negative ion mode.Among them,the different compounds in the negative ion mode were mainly organic acids,and 4 different compounds were identified in the positive ion mode.The cluster analysis results of the difference variables show that different liquors are clearly distinguished,and the cluster information is consistent with the real information of the Baijiu samples.(2)In order to analyze the non-volatile components in Baijiu liquor quickly,real-time direct injection mass spectrometry(DART-MS)was used for experiments.After optimized conditions,the highest ionic strength and material richness were obtained at a gas temperature of 450°C and a declustering voltage of 30 V.The data obtained by DART-MS is processed by PCA and OPLS-DA models for dimensionality reduction.In the PCA model,three principal components are used to characterize the overall difference of the sample.In the positive and negative ion modes,they represent 57.8% and 57.1% of the total sample variation,respectively.Different wine samples are well distinguished in the PCA and OPLS-DA models.The variable importance table is obtained through the OPLS-DA model,and a total of 18 different compounds of different series of liquors in the positive and negative ion modes of DART-MS are screened out.DART-MS was used to determine a batch of five samples only takes 1 min.Compared with UPLC-Q-TOF-MS,it takes 90 minutes to determine the same batch of samples,which greatly improved the detection efficiency.(3)The combination of GC-MS and SICRIT-MS is used for the rapid analysis of volatile compounds in Baijiu liquor.GC-MS is convenient and accurate for qualitative determination.A database of volatile compounds of different series of Baijiu liquor was establish by GC-MS.The mass spectrometry data obtained by SICRIT-MS is dimensionaly reduced by omics analysis technology.According to the three-dimensional treatment,the principal components scored well on the PCA model in the positive and negative ion modes.The three principal components represented 65.3% and 64.4% of the total variation of the sample.Different Baijiu showed good distinction in the PCA model.The OPLS-DA model extracts the difference variables,and after statistical testing,a total of 14 different compounds in the positive and negative ion modes are screened.The cluster analysis results show that the different compounds can better classify different series of Baijiu samples.The front-end database established by GC-MS was used to infer the types of differential compounds extracted by SICRIT-MS.The differential compounds with the highest VIP values in the positive and negative ion modes were ethyl caprylate and dodecanol.SICRIT-MS was used to determine a batch of five samples only takes 30 seconds.Compared with GC-MS,it takes 230 minutes to determine the same batch of samples,which greatly improved the detection efficiency.The differences of different flavors,different extraction stages,and different aging times of Chinese Baijiu were analyzed by variety of detection techniques in this study,omics analysis technology was used to accurately reflected the similarities and differences compounds information between different series of Chinese Baijiu,greatly improved the detection efficiency and Provided a reliable basis for Rapid analysis and identification of Chinese Baijiu.