Abstract: To extend the shelf-life pickled vegetables, in this study, we examined the preservative effect of ε-ploy-L-lysine (ε-PL) when combined with other preservatives and antioxidant (nisin, natamycin and tea polyphenols) on pickles. The results showed that the biopreservatives nisin and natamycin as well as the antioxidant tea polyphenols potently inhibited the growth of spoilage bacteria, and their effects were synergistic in combination. The optimal combination determined using response surface methodology was ε-PL 0.06 μg/mL, nisin 0.06 μg/mL, natamycin 0.035 μg/mL and tea polyphenols 0.40 μg/mL. In addition, this combination was more effective when added during seasoning that during rehydration of dried radish and increased the shelf-life to 21 days. The pickle maintained good quality during its shelf-life, and the total number of colonies, the number of coliforms, total acid and amino nitrogen content were in line with the national standard. This study can provide an experimental basis for the application of ε-PL in pickled vegetables.

Key words: ε-poly-L-lysine, natamycin, nisin, pickles, preservative effect