Effect of Different Modified Atmosphere Packaging on Microbial Quality, Oxidation and Colour of a Seasoned Ground Beef Product (Meatball)

摘要

The effects of different modified atmosphere packaging (MAP) on microbial quality, oxidation and colour of meatballs were investigated. Meatballs were prepared in our laboratory and packaged in vacuum or in different gases: combinations of O_2 (0, 2, 21%) and CO_2 (0, 33, 66, 100%) with N_2 as balance gas. Total microbial count, thiobarbituric acid reactive substances and colour were determined during storage at 3℃ for 3 weeks. Total microbial count remained unchanged at around 6.3 LogCFU/g in vacuum and 100% CO_2 packages after 7 days, and slightly increased afterwards. The microbial count was higher in other packages and increased to 7.6 LogCFU/g after 21 days storage. Oxidation was inhibited by reduced O_2 and increased CO_2 in the packages. Packages with low O_2 maintained colour (a-values) to a greater extent than the packages with higher O_2 levels. MAP containing 1-3%O_2 with 33%CO_2 inhibited microbial growth, oxidation and colour change in meatballs.