The pathogenic and spoilage bacteria associated with red meat and application of different approaches of high CO packaging to extend product shelf-life.

With the fast-global development of packaging techniques, the potential antimicrobial effect of CO, as a safe, cheap and readily available gas, makes it the integral component for packaging of meat products. The associated spoilage and/or pathogenic bacteria on raw meat may respond in different ways to elevated CO concentrations. The growth of some aerobic Gram-negative bacteria such as spp. is significantly inhibited but some LAB bacteria may be allowed to grow faster and dominate the product. The antimicrobial efficacy of enriched CO packaging is attributed to the rate of CO solubility in the product which is itself affected by the level of headspace CO, product pH, temperature and the ratio of headspace gas to product (G:P). This review, first, explores the varied range of beef and sheep meat spoilage and pathogenic bacteria and the intrinsic and extrinsic parameters that may influence the pattern of microbial growth and meat spoilage rate during storage. Then, the antimicrobial mechanism of elevated CO packaging will be discussed and the different approaches of achieving enriched CO packaging i.e. the traditional technique of flushing a desired gas mixture and/or using the new commercially developed CO emitters will then be compared in terms of their strengths, limitations and technical mode of action.