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

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 CO2 (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 degrees C for 3 weeks. Total microbial count remained unchanged at around 6.3 LogCFU/g in vacuum and 100% CO2 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 CO2 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%CO2 inhibited microbial growth, oxidation and colour change in meatballs. Copyright (C) 2009 John Wiley & Sons, Ltd.