P. SEMISULCATUS و دريايي P-INDICUS تاثير زمان نگهداري در سردخانه در كيفيت ميگو پرورشي

The Effect of Cold Storage on the Quality of Cultured P. Indicus and Sea P. Semisulcatus

In this research work the effect of cold storage on the quality of cultured and sea shrimp from Persian Gulf was investigated for 120 days. According to a time schedule, the samples were tested for changes in their organoleptic properties, total count of bacteria, pH, Total Volatile Nitrogen (TVN) and Peroxide value (pv). The Results indicated that taste, smell, flavour and colour of cultured shrimp remained natural for 90 days with its bacterial count dropping from 2.49* 10^3 to 7.7x 10^1 colonies/g. But after 120 days of cold storage pH and TVN increased from 7 to 7.7 and 14.4 to 31 mg/100g. respectively. After 60 dyas of cold storage pv increased from 1.7 to 2.7 milliequiyalents/ 1000 gr., then started to break down. The results for sea shrimp indicated that taste, smell, falvour and colour remained natural only for 30 days. After 120 days of cold storage, total bacterial count and pH changed from 2.21*10^4 to 2.01* 10^2 colonies/gr., and 7.1 to 7.9. whereas, after 60 days of cold storage TVN changed from 25.2 to 31 mg/100gr with pv increasing from 1.9 to 3.1, then starting to break down. After,20 days in cold storage pv was reduced to 2.4 milliequivalents/ 1000gr.