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 O₂ (0, 2, 21%) and CO₂ (0, 33, 66, 100%) with N₂ as balance gas. Total microbial count, thiobarbituric acid reactive substances and colour were determined during storage at 3°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 O₂ and increased CO₂ in the packages. Packages with low O₂ maintained colour (a‐values) to a greater extent than the packages with higher O₂ levels. MAP containing 1–3%O₂ with 33%CO₂ inhibited microbial growth, oxidation and colour change in meatballs. Copyright © 2009 John Wiley & Sons, Ltd.