Assessment of microbiological changes in fresh uncooked İnegöl meatballs stored under two different modified atmosphere packaging conditions

Abstract

Summary:This study was conducted to assess the microbiological changes in fresh uncooked İnegöl meatballs stored at 4°C under ambient (Control: C), and two modified atmosphere packaging (MAP) (M1: 30% O 2 , 40% CO 2 , 30% N 2 and M2: 60% O 2 , 30% CO 2 , 10% N 2 ) conditions. pH measurements and microbiological analyses for total aerobic mesophilic bacteria (TAMB), Pseudomonas spp., Brochothrix thermosphacta (B. thermosphacta), Enterobacteriaceae, coliform bacteria, lactic acid bacteria (LAB), and yeast and molds were performed on days 0, 2, 5, 7, 10, 12, 15, 20 of storage. Packaging under ambient atmosphere resulted in an increase in the counts of all microorganisms and pH values. TAMB in C group composed of mainly Pseudomonas spp. and B. thermosphacta. There was restricted growth of Pseudomonas spp. in both MAP groups. There was no change in TAMB and B. thermosphacta counts of M1 group, in contrast to an increase in LAB counts. In M2 group, an increase in TAMB and a decrease in B. thermosphacta with no change in LAB counts was observed. Results indicate that M2 group MAP, with less growth of spoilage bacteria, was apparently more beneficial for refrigerated storage of İnegöl meatballs.Key words: Meatball, microbial quality, modified atmosphere packaging.