Document Type : Research Paper
Authors
1
Depatment of Fisheries, Faculty of Natural Resources, University of Tehran, I.R.IRAN
2
Ali Taheri: Department of Fisheries, Chabahar Marine University, Chabahar, I.R.IRAN
3
Amin Oujifard: Department of Fisheries, University of KhalijFars, I.R.IRAN
Abstract
Golden gray mullet (Lizaaurata) is one of the valuable fishes inhabited in Caspian Sea, which
is captured in large volumes in northern parts of Iran. However, similar to other fishes, Golden
gray mullet is susceptible to bacterial spoilage and the quality of the fish will be degraded
during the storage time. Therefore, the purpose of the present study was to investigate the
effects of gamma radiation, as a non-thermal fish processing method, on the microbiological
properties and shelf-life extension of Golden gray mullet fillets during chilled storage (4°C).
Experimental fish were filleted, irradiated at different doses (0, 1, 2, 3 and 5 kGy) and then
stored in refrigerator for 35 days. Microbial quality changes were evaluated by enumeration of
total viable count (TVC), Pseudomonas, Lactic acid bacteria (LAB), H2S producing bacteria
and Enterobacteriaceae over the experimental period on the day of 1, 5, 10, 15, 20, 25, 30
and 35. The results obtained from this study showed that the shelf life of Golden gray mullet
stored at the refrigeration temperature, as determined by overall microbial load, is 10 days for
non-irradiated Golden gray mullet. However, samples treated with gamma irradiation showed
better quality during storage. The results revealed that radiation at a high dose (5 kGy) was
inhibited the growth of microorganisms, and irradiation at a medium dose of 3 kGy could
be used to control the microbial load indices of Golden gray mullet for up to 35 days at the
refrigeration temperature without adverse effects on the fish quality and acceptability.
Keywords
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