mohamadali khanlar

Pacific white shrimp (Litopenaeus vannamei) is an important worldwide cultured species. The evaluation of quality and shelf-life of the shrimp is imperative before utilizing preservative within the harvesting. The effect of slurry ice on the quality of Pacific white shrimp during chilling storage was investigated and compared with flake ice and refrigerator. In this manuscript, the effect of different cold storages conditions including refrigerator (stored at 4°C) (treat A), flake ice (treat B) and Slurry ice (treat C) up to 12 days was investigated. To analyze chemical characteristics, and freshness indicators of Pacific white shrimp, changes in total volatile base nitrogen, thiobarbituric acid, titratable acidity (TA) and microbial count of white shrimp during 12 days (every two days) storage was investigated. Increases of the total volatile base nitrogen and thiobarbituric acid reactive substance, values in shrimp treated with slurry ice were found to be significantly slower during slurry ice storage than during flake ice storage (P<0.05). The shelf life of ice stored Pacific white shrimps was determined to be 8 days. Contrarily, the aerobic plate count (APC) and psychrophilic bacterial counts (PTC) compared to two treatments exhibited significant increases during iced storage (P<0.05). Nevertheless, the results demonstrated that storage in slurry ice immediately after harvesting caused quality stability during the cold storage.

Due to the potentiality and rapid spoilage of edible aquatic, many technologies have been developed to increase their shelflife. In this research, the effect of modified atmosphere (40% carbon dioxide and 60% nitrogen), vacuum and air atmosphere packaging on the physical, chemical and microbiological changes of Oncorhynchus mykiss fillet during refrigerated storage (4°C) were studied. Chemical (total volatile base nitrogen (TVB-N) and thiobarbituric acid (TBA)), physical (pH, drip loss and colorimetry) and microbial parameters (total bacterial count (TVC) and psychrotrophic count (PTC)) were measured at 0, 3, 6, 9, 12, 15 and 18 days. The results showed that the fillets packed with modified atmosphere maintained the quality and pysical properties of fillets for 15 days. While the quality and pysical properties of control samples strongly decreased (P