E3 Journal of Microbiology Research

E3 Journal of Microbiology Research Vol. 1 (1) pp. 016-022, June 2013; © E3 Journals

The effects of modified atmosphere packaging on microbiological, chemical properties of hot smoked Rainbow Trout (Oncorhynchus mykiss) fillets

Abstract

Research was conducted to determine the effects of modified atmosphere packaging (MAP) on hot smoked rainbow trout (Oncorhynchus mykiss) fillets. Hot smoked was applied to fillets after they were treated with brine method and seperated into groups. The first group was control group and vacuum packaging was applied to this group. The second group was packed in the modified atmosphere (50% CO2+50% N2). Fillets stored at 41C were subject to microbiological (total aerobic mesophilic bacteria, psychrotrophic bacteria, Pseudomonas, lactic acid bacteria, Enterobacteriaceae, yeast and mould) and chemical (pH, thiobarbituric acid reactive substances-TBARS, total volatile base nitrogen-TVB-N) analyses on certain days (0, 5, 10, 15, 20, 25, 30, 40, 50 and 60th days) of storage. The growth of microorganisms was slower in modified atmosphere packaging than vacuum. But Pseudomonas and Enterobacteriaceae were determined under the limit (<102 cfu/g) both during the stored with vacuum and modified atmosphere packaging. It was determined that packaging method (vacuum and MAP) had very significant (p<0,01) on the TBARS and TVB-N values. Modified atmosphere packaging had lower TBARS and TVB-N values than vacuum packaging (p<0,05). Storage duration had significant (p<0,01) effects on pH, TBARS and TVB-N values. TBARS and TVB-N were increased by longer storage (p<0,05).

Keywords: Rainbow trout; hot smoking; vacuum ;MAP; shelf life