An effective lacticin biopreservative in fresh pork sausage

Lacticin 3147 is a novel heat-stable bacteriocin, produced by Lactococcus l actis DPC 3147, that exhibits a broad-range inhibition spectrum similar to nisin. In this study, the effect of lacticin 3147 and nisin on the shelf li fe of fresh pork sausage and their ability to control pathogens (Clostridiu m perfringens DSM 756, Salmonella Kentucky ATI) and nonpathogenic Listeria innocua DPC 1770 was investigated. The following preservative regimens were evaluated, both in broth and sausage systems: (i) 450 ppm of sodium metabi sulphite; (ii) 500 IU g(-1) or ml(-1) of nisin, (iii) 2500 arbitrary units (AU) g(-1) or ml(-1) of lacticin 3147; (iv) 2% sodium lactate and 500 TU of nisin; (v) 2% sodium citrate and 500 IU g(-1) or ml(-1) of nisin; (vi) 2% sodium lactate and 2500 AU g(-1) or ml(-1) of lacticin 3147, (vii) 2% sodiu m citrate and 2500 AU g(-1) or ml(-1) of lacticin 3147, (viii) 2% sodium la ctate, and (ix) 2% sodium citrate. There was no significant difference in t he activity of nisin and lacticin 3147 against any of the target strains us ed, both bacteriocins performing significantly better than sodium metabisul fite against gram-positive strains in broth systems. Trends indicate that t he combination of organic acids with either bacteriocin enhanced its activi ty against Salmonella Kentucky and L. innocua and was particularly effectiv e in the inhibition of C. perfringens in fresh pork sausage. In addition, l acticin 3147 combined with either sodium citrate or sodium lactate maintain ed significantly lower (P < 0.05) total aerobic plate counts for the durati on of the trials and may function as an alternative to sodium metabisulfite in the preservation of fresh pork sausage.