Correlation Analysis Of Flavor Substances And Microbial Flora During The Fermentation Process Of Salted Radish With Different Fermentation Forms

Exploring the relationship between the flavor substances of traditional salted vegetables and microbial flora can provide data reference for its flavor regulation and large-scale production and processing.In this study,three salted radishes were prepared in wet,semi-dry,and dry states with reference to traditional techniques.The changes in basic physical and chemical properties,flavor substances,sensory characteristics,and bacterial flora during the fermentation process were investigated to determine the core flavor substances and advantages.Flora,and its correlation analysis,the main results are as follows:1.The water content and water activity of the three fermented salted radishes are obviously different.The p H of the wet salted radish drops rapidly,the fermentation speed is faster,and the p H of the semi-dry and dry salted radish remains at 4.5 Above,fermentation is slow,and the total acid concentration gradually increases with fermentation.2.The concentration of glucose,fructose,and free amino acids in wet salted radish gradually decreased with fermentation,and the concentration of lactic acid was higher.The characteristic aroma was acetic acid.The semi-dry and dry salted radishes have higher concentrations of glucose,fructose,succinic acid,malic acid,and proline.The characteristic aromas of the semi-dry salted radishes are cis-2-pentenol and 1-pentene-3-alcohol,ethane,1,1-bis(methylthio)ethane and methoxybenzene oxime,the characteristic aroma of dry salted radish is dimethyl trisulfide,dimethyl tetrasulfide,hex Acid,heptaldehyde,3-hydroxy-2-butanone,2-n-pentylfuran and phenylethanol.3.The wet salted radish has the best sensory on the 5th day of fermentation,with bright white color,crisp and tender texture,and mainly sour taste.The semi-dry and dry salted radishes had the best sensory on the 30 th day of fermentation,with bright yellow color and rich aroma,mainly fresh and salty sweet.Color difference analysis showed that the wet salted radish changed from white to dark,the semi-dried salted radish changed from yellowish green to red yellow,and the dry salted radish changed from red yellow to dark red.The texture data reflect that there is a big difference in taste between wet salted radish and semi-dry and dry salted radish.4.The microbial community of the three salted radishes is dominated by bacteria.The wet salted radishes were predominantly Leuconostoc and Weissella in the early stage of fermentation,and Lactobacillus in the late stage of fermentation.The semi-dry and dry salted radishes are mainly Pantoea,Pseudomonas,Rosenbergiella,Leuconostoc,Glutamicibacter,Erwinia and so on.5.The lactic acid of wet salted radish is positively correlated with Lactobacillus,and acetic acid is positively correlated with Lactobacillus,Pantoea,Erwinia.The sweetness and umami amino acids of semi-dried salted radish are positively correlated with Serratia,Enterobacter,Exiguobacterium and Acinetobacter.The characteristic aroma is positively correlated with Acinetobacter,Enterobacter and Leuconostoc.The sweet amino acids of dry salted radish are positively correlated with Enterobacter,Weissella and Leuconostoc,and the characteristic aroma is positively correlated with Weissella,Enterobacter and Rosenbergiella.