The properties of faba bean (Vicia faba L.) protein isolate (FPI) gels depend on their starting protein material and can be modulated by the addition of polysaccharides. In order to investigate the interplay between these two factors, commercial FPI (FPI₁) and FPI prepared in-house (FPI₂) were used to fabricate glucono-delta-lactone-induced gels, with or without dextran (DX) addition. FPI₁ exhibited lower solubility in water and a larger mean particle size, likely because it experienced extensive degradation due to the intense conditions involved in its preparation. The FPI₁ gel showed a similar water-holding capacity as the FPI₂ gel; however, its hardness was lower and viscoelasticity was higher. After DX addition, the hardness of both FPI gels decreased, while their water-holding capacity increased. Interestingly, DX addition decreased the viscoelasticity of the FPI₁ gel but enhanced the viscoelasticity of the FPI₂ gel. The microstructural analysis demonstrated that the density of the aggregation network decreased in the FPI₁ gel after DX addition but increased in the FPI₂ gel. This was consistent with the changes observed in the dominant protein interaction forces in these gels after DX addition. Overall, these findings have the potential to guide ingredient selection for the tailored preparation of FPI gels.

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.