Bacteriocin Application in Meats: The Protective Culture Approach

Abstract

Meats are worldwide popular food commodities. Their nutrient composition makes them prone to growth and propagation of spoilage microorganisms and common food-borne pathogens. Hence, adequate preservation technologies are necessary to extend the shelf-life of perishable meat products, which is a main concern for meat industries. Biopreservation sets itself as a quality alternative to traditional preservation by using added microorganisms, generally lactic acid bacteria (LAB) as protective cultures (PC). From this perspective, LAB can be added not only to prolong the shelf-life but to preserve the microbial and/or sensorial quality of the product. The microbial antagonism of LAB against undesirable microorganisms has been attributed in many cases to metabolic products such as organic acids or bacteriocin production and changes in the physicochemical environment (pH, CO2 production) or a combination of these factors. Bacteriocin application in meats can be conducted by in situ or ex situ production. While the latter implies the addition of the bacteriocin to the product ?with the consequent legal requirements-, in situ application comprise the use of living bacteria that produce the antimicrobial substance in the meat substrate. Bacteriocinogenic strains can be used either directly as starter cultures, as adjunct or co-cultures in combination with a starter culture, or as PC (especially in the case of non-fermented meats). Having GRAS status, bacteriocinogenic LAB cultures can be safely added to meats, which revised their major advantage regarding food preservation. The operational advantages of PC include additive-free preservation, natural image, and food safety improvements. During the last decades, hundreds of strains from many LAB species have been extensively studied for the preservation of meats and meat products showing promising results. PC application requires the presence of high viable populations guaranteed during the product shelf-life. Encapsulation of PCs in protective liposome coating or a packaging device with a culture release mechanism can protect cultures. As an example, novel technologies analyze the direct incorporation of bacteriocinogenic strains into polymeric matrices. This chapter reviews the recent applications of bacteriocin-producing PC in meats and meat products throughout the world. Information given will provide an integrated approach on this topic.