ABSTRACT
Most microorganisms are capable of producing a large variety of molecules. These molecules may be inhibitory either to the producing cell or to other bacteria and include organic acids, toxins, lytic enzymes, antibiotics, and bacteriocins. Bacteriocins are heterogeneous with respect to inhibitory spectrum, molecular size, stability, physical and chemical properties, and mode of action. Department of Agriculture confirms the safety and evaluates efficiency of novel food preservatives. Many newly isolated bacteriocins are attracting attention of researchers and industries as potent food preservatives that can be used as purified substances, crude extracts, or as a substance synthesized by food-grade microorganisms during food processing/fermentation. Toxicity studies conducted earlier clearly indicate that nisin is safe for applications as a food preservative. Microbial resistance to bacteriocins may become an issue as their food-preservative use becomes more wide spread. Combining preservation techniques is a powerful tool for extending shelf life, especially of minimally processed foods.
