An assessment of the microbial quality of "doner kebab" during cold storage: Effects of different packaging methods and microwave heating before consumption

Abstract

In the current study, doner kebabs packed with different packaging methods (air packaging [AP], modified atmosphere packaging [MAP], vacuum packaging [VP] and sous vide packaging [SVP]) were evaluated for their microbial quality during storage at 4 degrees C. In addition, the effect of microwave heating before consumption on the microbial quality of doner kebabs was also investigated. Total mesophilic aerobic bacteria and total psycrophilic aerobic bacteria counts of doner kebabs increased during storage and reached to 6.48, 8.27, 8.15, 3.96 and 5.58, 8.53, 8.63, <1.00 log cfu/g in AP (9th day), MAP (29th day), VP (29th day) and SVP (99th day) groups, respectively. Although coliform, Escherichia coli and Staphylococcus aureus counts of doner kebabs were below 3 MPN/g, 3 MPN/g, 2 log cfu/g in all groups, respectively; no Clostridium perfringens and Listeria monocytogenes was detected in any of the groups during storage. Microwave heating was found effective on reducing the microbial load of doner kebabs. It was concluded that without any additional preservation techniques, the SVP prolonged the shelf life of doner kebabs more than 20, 6, and 5 times comparing to AP, MAP, and VP groups, respectively.