【作者】 陈淑湘；

【导师】 林向东；

【作者基本信息】 海南大学 ， 海洋生物学， 2012， 硕士

【摘要】 本研究通过理化评定法和质构评定法(TPA)比较不同致死方式、不同冻结方式和不同冷藏温度对凡纳滨对虾品质的影响。本研究中理化法评定指标包括感官评定、pH值和TVB-N值(挥发性盐基氮),质构评定参数包括硬度、弹性、内聚性和咀嚼性。研究结果和结论如下：(1)用电导率法测得凡纳滨对虾肌肉的冰点为-1.5℃,郭红等用传统方法测得凡纳滨对虾冰点为(-1.4±0.1)℃一致。(2)采用冰水猝死和自然致死两种不同的致死方式对凡纳滨对虾进行处理,观察其在4℃下的新鲜度变化情况。结果表明,冰水猝死处理能更好的保持凡纳滨对虾的各项新鲜度指标；质构评定中冰猝死组的硬度、弹性和咀嚼性等参数更接近新鲜原料值,而自然致死处理虾的内聚性数值与新鲜原料接近。(3)将凡纳滨对虾置于-7℃、-21℃和-70℃条件下冻结至-7℃,结果表明,-7℃下冻结属于缓冻,而-21℃和-70℃条件下冻结属于速冻。解冻后分别进行质构分析,表明速冻组对虾肌肉的硬度、弹性和咀嚼性明显的比缓冻组更接近新鲜值。从操作条件上看,-21℃下更易准确掌控冻结过程,因此认为-21℃为较好的速冻温度。(4)将冰猝死处理后的凡纳滨对虾置于-7℃和-21℃温度条件下进行贮藏试验。试验结果表明,凡纳滨对虾在-7℃条件下保藏期可达30天,而在-21℃条件下保藏期超过54天。保藏18天左右时,-7℃条件下虾肉的弹性、咀嚼性和内聚性与新鲜原料的值接近,外观和理化指标与-21。C保藏条件下的相差不大,证明微冻是一种短期保鲜贮藏凡纳滨对虾较好的方式。更多还原

【Abstract】 In this study, we compared the quality of Penaeus vannamei Boone With physical and chemical method which death, freeze by different ways and different temperature preservation. In this study, the parameters of physicochemical method are sensory evaluation, pH value and TVB-N value. The parameters of Texture Profile Analysis are Hardness, Springiness, Cohesiveness and Chewiness. The results are as follows:(1) According to investigate the freezing point of Penaeus Vannamei Boone by conductivity meter, we found its freezing point was-1.5℃It consistents with the South American white shrimp freezing point of (1.4+-0.1)℃which determined by guo hong.(2) The Penaeus vannamei Boone were killed by two different ways, they are ice sudden death and natural death. And then the shrimp preservations in4℃freeze. The results show that Ice sudden death keep physicochemical freshness indicator better. The Cohesiveness of natural death shrimp is better than ice sudden death shrimp. And the Hardness, Springiness and Chewiness of ice sudden death shrimp are better than the natural death.(3) The Penaeus vannamei Boone was frozen in-7℃,-21℃and-70℃. The results show that frozen in-7℃is slow-freeze, frozen in-21℃and-70℃are quick-freezes. To Texture Profile Analysis after thawing, it shows that the Hardness, Springiness and Chewiness of quick-freeze group are better than the slow-freeze group. For the operation, frozen in-21℃can control more exactly. So frozen in-21℃is best frozen way.(4) The Penaeus vannamei Boone was preservation in-7℃and-21℃temperature conditions after ice sudden death. The results show that period of-7℃condition is about30days, and period of-21℃conditions is more than54days. When short-term preservation (18days or so), the Springiness, Chewiness and Cohesiveness of the-7℃are better than-21℃temperature conditions.更多还原