Impact of Lactic Acid Bacteria Screening on the Quality of Fermented Sausage

Utilizing a sausage model and principal component analysis (PCA), a strain of Lactobacillus plantarum that significantly improved the flavor substance of sausage was selected. It was added to the sausage, and the pH, Aw, color, peroxide value (POV), thiobarbituric acid (TBARS), and volatile flavor substances of Sichuan sausage production were measured at 0, 1, 3, 7 and 14 d, using the uninoculated group as control. A partial least squares discriminant analysis model (PLS-DA) was applied to evaluate the characteristic flavor substances in sausages with VIP (variable important in projection) > 1 and P < 0.05 as screening conditions. Results showed that, the pH of control and Lactobacillus plantarum-fermented sausages declined and then gradually rose with fermentation time. The Aw reduced dramatically, the POV and TBARS increased significantly, while there was no significant change in color (P>0.05). And the pH, Aw, POV and TBARS values were significantly lower in Lactobacillus plantarum inoculated sausages compared to the control group. In comparison to the control group, the sausages inoculated with Lactobacillus plantarum had significantly higher concentrations of alcohols, ketones, and esters, as well as significantly enhanced the concentrations of characteristic flavor substances (isovaleric acid, 3-hydroxy-2-butanone, phenylethylaldehyde and phenylethanol). In summary, Lactobacillus plantarum M-25 selected by the sausage model was effective in enhancing the quality and flavor characteristics of sausages.