熟制麻辣小龙虾冷藏和冻藏条件下的品质变化

摘要

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.%研究熟制麻辣小龙虾在冷藏和冻藏条件下的品质变化,将小龙虾油炸后拌料入味,真空包装并进行沸水煮制杀菌(沸水煮制20 min后快速冷却),分别在4 ℃和－18 ℃条件下贮藏,通过感官评分、菌落总数、大肠杆菌数量、总挥发性盐基氮(total volatile base nitrogen,TVB-N)值、pH值及食盐含量测定对麻辣小龙虾的品质变化进行研究.结果表明:从感官评定结果、菌落总数和TVB-N值综合评判,4 ℃冷藏和－18 ℃冻藏的麻辣小龙虾能够保持最佳品质的贮藏时间分别为4 周和4 个月;在保质期内,麻辣小龙虾的菌落总数＜4.7 (lg(CFU/g)), TVB-N值＜30 mg/100 g,pH值在弱碱性范围内变化;4 ℃冷藏小龙虾贮藏前3 周的食盐含量呈逐渐升高趋势(达1.99%),贮藏3 周后变化不显著(P＞0.05),而－18 ℃冻藏小龙虾的食盐含量变化缓慢,保持在1.6%～1.8%范围内.经感官评定,保质期内的麻辣小龙虾风味鲜美、品质优良.