不同冷藏温度条件下金枪鱼保鲜效果的分析比较

Effect of storage temperature on quality and the freshness of tuna

为探究不同温度下金枪鱼的保鲜效果,实验设置了-4℃微冻贮藏、-2℃冰温贮藏和4℃冷藏三组实验,以p H、K值、组胺、挥发性盐基氮(TVB-N)、高铁肌红蛋白百分含量以及微生物等理化指标的变化为依据测定了金枪鱼在不同贮藏温度下的品质变化,结果表明:随着贮藏时间的延长,不同温度下金枪鱼的K值、组胺、TVB-N和高铁肌红蛋白含量以及菌落总数均出现不同程度的上升,且温度越高上升速率越快,微冻组和冰温组其TVB-N值到60 h时分别为10.83 mg/100 g和12.77 mg/100 g<15 mg/100 g(一级鲜肉指标值),而4℃冷藏组在56 h时TVB-N值达到17.12 mg/100 g超过一级鲜度肉指标,且冷藏组组胺变化明显而微冻组和冰温组在整个贮藏过程中组胺变化平稳。综合各项理化及感官指标可知金枪鱼在微冻和冰温条件下保鲜效果明显优于冷藏。

The quality changes of tuna,storage in-4 ℃（ partial frozen）,-2 ℃（ freezing temperature） and 4 ℃（ cold storage）,was studied by sensory assessment,p H,K values,histamine concentration,total volatile basic nitrogen（ TVB- N）,met- myoglobin concentration and aerobic bacterial count. The results showed that the K values,histamine concentration,total volatile basic nitrogen（ TVB- N）,met- myoglobin concentration and aerobic bacterial count of tuna increased during storage,regardless of the storage temperature,increasing at a faster rate at higher storage temperatures,the TVB- N value stored for sixty hours at- 4 ℃ and- 2 ℃ were 10.83 mg /100 g and12.77 mg /100 g respectively,however,it reached 17.12 mg /100 g and exceed the limit of 15 mg /100 g when tuna was store at 4 ℃ for fifty- six hours. The increase of histamine concentration was not evidence at both- 2 ℃ and-4 ℃ throughout the storage,but it rose remarkably at 4 ℃.Compared with cold storage,the partial freezing and controlled freezing point condition would increase the shelf- life of tuna obviously.