Dynamic Changes and Correlation Analysis of Chemical Components Contents and Microbial Quantity in Naturally Fermented Sauerkraut

In order to explore the dynamic changes and correlations between chemical components contents and microbial quantity at different fermentation time in traditional Chinese sauerkraut. Conventional culture assay was used to analyse microbial quantity, chemical indexes and correlation analysis of them during sauerkraut fermentation. The results showed that, with the prolongation of fermentation time, pH and soluble protein content decreased, total acid contents increased, the contents of reducing sugar, nitrite, and amino acid nitrogen all increased and then decreased during the fermentation process. The total number of bacteria, coliform bacteria and the lactic acid bacteria increased and then decreased. The number of coliform bacteria eventually became zero finally. The amount of yeast increased, decreased and then increased slightly. The correlation analysis showed that, the number of lactic acid bacteria was significantly negatively correlated with the pH, the number of coliform bacteria, and the soluble protein contents (p<0.01). The number of yeasts was positively correlated with nitrite, reducing sugar and amino acid nitrogen contents (p<0.01). The number of coliform bacteria was positively correlated with pH value, reducing sugar, soluble protein and amino acid nitrogen contents (p<0.01). There was a positive correlation between total bacterial number and amino acid nitrogen contents (p<0.05).The study indicated the significant correlations and complex relationships between chemical components comntent and microorganism quantity in traditional Chinese sauerkraut system, which provided theoretical basis for improving the coordination between microorganisms and chemical indexes in the fermentation environment.