Study On The Marker Metabolites Of Brewing Soy Sauce And Vinegar Based On Metabonomics

Soy sauce and vinegar have been brewed in China for thousands of years.They are rich in many flavor substances and active substances.They can not only improve the taste of food,but also have the functions of antioxidation,lowering blood pressure,lowering blood fat,etc.They have become the essential condiment in our people’s daily life.Many researchers have used a variety of technical methods to study the composition of brewing soy sauce,but few researchers have studied the differences of different kinds of brewing soy sauce.Therefore,Therefore,this study is based on metabolomics technology,using liquid chromatography-mass spectrometry to detect different kinds of soy sauce samples,and uses multivariate statistical analysis to find the different metabolites between light soy sauce and dark soy sauce,different grades of soy sauce,vinegar from different places of origin,vinegar of different colors.On this basis,three kinds of bulk soy sauce samples are added and their quality was analyzed.There are two parts in this experiment: the first part is the metabolomics analysis of the soy sauce sample.The experiment uses ultra high performance liquid chromatography in ultra-high performance liquid chromatography tandem four-bar orbital ion trap high resolution mass spectrometry(UHPLC-Q Exactive Obitrap MS)to analyze the soy sauce.The sample was initially analyzed to obtain the total ion chromatogram of the sample,and then the mass spectrometry data was imported into Compound Discoverer 2.1 software.Light soy sauce,dark soy sauce and bulk soy sauce samples and different grades of soy sauce samples were grouped,analyzed separately,and manually screened.The appropriate ratio value is used to find the differential metabolites between the groups,and the results of the MS2 database are used to identify and analyze these substances.The second part is the metabolomics analysis of vinegar samples.The same conditions for processing soy sauce samples,grouping and analyzing vinegaraccording to different origins(Shandong,Shanxi,Jiangsu)and different vinegar color(colorless,light,brown).The appropriate ration value was manually selected to find the different metabolites among each group,and these substances were qualitatively analyzed combined with the results of secondary mass spectrometry data.In the first part of the experimental results,21 kinds of different metabolites were found between the dark soy sauce and the light soy sauce,mainly including esters,acids,alcohols,ketones,amino acids and their reactants in the light soy sauce samples,and coumarin derivatives in the dark soy sauce samples.Based on these different metabolites,it was speculated that some small metabolites were added into the dark soy sauce in the re-sunning stage The Maillard reaction of anise,clove,tarragon and other spices has transformed some amino acids;in the grouping results of different grades of soy sauce,five different metabolites were screened from the super-grade soy sauce and the first grade soy sauce,including esters,heterocyclic compounds and carboxylic acid compounds;17 different metabolites were screened from the super-grade soy sauce and the third-grade soy sauce,mainly including 11 kinds of differential metabolites,mainly ketone and acid compounds,were screened from the first-grade soy sauce and the third-grade soy sauce.In this group,the content and quantity of amino acids and active substances decreased step by step according to the grade.The super-grade soy sauce was better than the first grade soy sauce,the first-grade soy sauce was better than the third-grade soy sauce,which also confirmed the production process of different grades of soy sauce,The addition requirements of "first soy sauce" and "second soy sauce";no matter which group the bulk soy sauce is in,the amino acids and active substances are very different,and there are few other flavors except salty taste in the taste.In the second part of the experimental results,8 different metabolites were screened out from Jiangsu vinegars and Shandong vinegars,including carboxylic acids,ketones,amides and lipids.Shandong vinegar and Shanxi vinegar had 14 kinds of substances,including carboxylic acids,amides,esters,ketones,ethers and heterocyclic substances.The different metabolites from Jiangsu vinegars and Shanxi vinegars had 13 kinds of substances,including carboxylic acids,heterocyclic compounds,amides and esters.Zhenjiang Hengshun vinegars in Jiangsu vinegar samples are the most different from vinegar from other places.The raw materials are mainly glutinous rice and japonica rice from Hengshun.According to the different metabolites,they may also be supplemented with ingredients such as beans,traditional Chinese medicine or vanilla spice,wheat bran and so on.The raw materials of Shandong vinegar samples are mainly rice and ingredients containing protein such as wheat and wheat flour.The raw materials of Shanxi vinegar samples are mainly sorghum with low solubility protein.It may be the main reason why amino compounds in Shanxi vinegar samples are lower than other vinegar samples.In addition,1-furyl-β-carboline-3-carboxylic acid is the marker metabolite of Jiangsu vinegars,which is different from Shandong vinegars and Shanxi vinegars.There are 15 kinds of different metabolites in dark vinegars and light vinegars,including carboxylic acids,esters,alcohols,amides,ketones and heterocyclic compounds.There are 14 kinds of different metabolites in light vinegars and colorless vinegars,including carboxylic acids,amides,amines and esters.There are17 kinds of different metabolites in darkd vinegar and colorless vinegar samples,including amides,carboxylic acids,esters,amines,ketones and alcohols.Dark vinegars may contain more legumes on the raw materials than light vinegars,but colorless vinegars are very different from others,that may be due to the fact that the brew process of white vinegars is easier than mature vinegars and rice vinegars,and white vinegars are fermented with rice and edible alcohol as raw materials with short fermentation time.Unknown compound 3477 is the marker metabolite of dark vinegars different from others.2-Methoxy-5-methylaniline,L-Phenylalanine,Valylproline,Leucylproline,4760,Midodrine,(3S,8aS)-3-(4-Hydroxybenzyl)hexahydropyrrolo[1,2-a]pyrazine-1,4-dione and Methohexital are common in mature vinegars and rice vinegars,and they are marker metabolites that can distinguish mature vinegars and rice vinegars from colorless vinegars.