Effects of Antioxidative Lactic Acid Bacteria on Bacterial Community Dynamics, Physicochemical Properties, and...

This study aimed to screen lactic acid bacteria (LAB) with enhanced antioxidant activity and evaluate their potential as starter cultures for dry-cured fermented sausages by assessing their effects on oxidative stability and physicochemical quality during processing. The antioxidant activities of different cellular fractions of five LAB strains were first compared, and the results indicated that the antioxidant activity was mainly associated with extracellular metabolites. Based on their good in vitro antioxidant activities and oxidative tolerance, Leuconostoc carnosum AMS1 and Lactiplantibacillus plantarum P4 were subsequently selected as starter cultures for sausage fermentation. Individual inoculation with AMS1 and P4 modulated the bacterial community structure during fermentation and reduced the abundance of opportunistic pathogens. Compared with the uninoculated control, starter inoculation accelerated acidification, reduced water activity, and positively modulated color and texture properties. Moreover, inoculation improved oxidative stability, as indicated by reduced thiobarbituric acid reactive substances (TBARS) levels and lipoxygenase (LOX) activity, and alleviated protein oxidative changes, as evidenced by lower carbonyl accumulation, reduced sulfhydryl group loss, and a lower increase in surface hydrophobicity. In conclusion, AMS1 and P4, particularly AMS1, showed potential as antioxidative starter cultures for dry-cured fermented sausages by improving physicochemical quality and oxidative stability during fermentation and maturation.