Quality Change of Cooked Spicy Crayfish during Refrigerated and Frozen Storage
WU Chenyan1, WANG Xiaoyan1, WANG Yang2, MA Lizhen1,*
1.National R&D Branch Center for Conventional Freshwater Fish Processing (Tianjin), Tianjin Collaborative Innovation Laboratory of Aquatic Product Processing and Quality Safety between Schools and Enterprises, College of Food Science and Biotechnology, Tianjin Agricultural University, Tianjin 300384, China; 2.Tianjin Key Laboratory of Aquatic Ecology and Aquaculture, College of Fisheries, Tianjin Agricultural University, Tianjin 300384, China
Abstract：This work aimed to study the quality changes of cooked spicy crayfish at refrigerated and frozen temperatures. Crayfish were deep fried, seasoned, vacuum packaged, pasteurized in boiling water for 20 minutes, quickly cooled down, and then stored at 4 ℃ or –18 ℃. Sensory evaluation, total bacterial count, E. coli count, total volatile base nitrogen (TVB-N) value, pH value and salt content were determined. Results showed that the optimal storage time of spicy crayfish was 4 weeks and 4 months at 4 ℃ and –18 ℃, respectively as determined by taking into account sensory evaluation, total bacterial count and TVB-N value. During this period, the total bacterial count was less than 4.7 (lg(CFU/g)), the TVB-N value was smaller than 30 mg/100 g, and the pH value varied in a weakly alkaline pH range. The salt content continuously increased (up to 1.99%) during the first 3 weeks at 4 ℃, but did not significantly change during the subsequent 3 weeks (P > 0.05). During frozen storage, the salt content varied slowly in the range from 1.6% to 1.8%. Sensory evaluation revealed that the spicy crayfish maintained delicious flavor and good quality during the shelf life.
2018, Vol. 32 
