Influence of various ions on the antimicrobial stability of nisin

In order to improve the antibacterial stability of nisin and broaden its application in the food industry, effects of several phosphate, EDTA-Na2 and sodium citrate on the antibacterial activity of nisin were studied. The results showed that phosphate, EDTA-Na2, and sodium citrate had significant protective effect on the antibacterial activity of nisin and the order of the protective effect was as follows:sodium hexametaphosphate>EDTA-Na2>sodium tripolyphosphate>sodium citrate>sodium dihydrogen phosphate>sodium hydrogen phosphate. After heated at pH6. 8 and 121℃ for 20min, the antimicrobial activity of nisin decreased by 7. 25% and 10. 2% with the addition of sodium hexametaphosphate and EDTA-Na2 respectively.