暂养时间对鳙肌肉品质和营养价值的影响

Effects of purging time on meat quality and nutritional value of Aristichthys nobilis

为了探索暂养对鳙(Aristichthys nobilis)肌肉品质和营养价值的影响,本研究检测了围网捕捞后暂养0~4周的鳙肌肉质构特性、氨基酸和脂肪酸组成以及血液中部分生化指标与抗氧化指示酶活性。质地多面剖析法检测结果显示:经过3周暂养鳙肌肉的硬度和咀嚼性显著降低,而鳙肌肉的弹性显著升高。氨基酸和脂肪酸成分分析结果显示,2周的暂养处理提高了鳙肌肉必需脂肪酸和多不饱和脂肪酸的相对含量,3周的暂养处理增加了鳙肌肉呈味氨基酸和必需氨基酸的含量。除此以外,暂养2周的鳙血浆谷丙转氨酶活性显著低于其它暂养时间;暂养2周的鳙血浆抗氧化酶超氧化物歧化酶、过氧化氢酶和谷胱甘肽过氧化物酶活性达到最大值,而脂质过氧化终产物丙二醛在该暂养时段含量最低,表明适时的暂养处理可以有效提高鳙血浆中抗氧化酶的活性。结果表明,适时的暂养处理有助于提高鳙的肌肉品质和营养价值,降低捕捞应激以利于运输。

The meat characters,amino acids and fatty acids compositions,and plasma indexes during 4-week purging were evaluated to study the effects of purging time on muscle quality and nutritional value of Aristichthys nobilis.The texture profile analysis showed that the hardness and chewiness of A.nobilis muscle were significantly decreased,and the springiness was significantly elevated after three weeks purging.The levels of delicious amino acids and essential amino acids of fish muscle at three weeks purging,and the levels of essential fatty acids and polyunsaturated fatty acids at two weeks purging were significantly higher than those at other purging periods,which indicated that appropriate purging time would improve the nutritional value of fish.In addition,the activity of alanine aminotransferase in plasma of A.nobilis treated with two weeks purging was significantly lower than that of fish at other purging times.Simultaneously,superoxide dismutase,catalase and glutathione peroxidase showed the highest activities while malonaldehyde showed the lowest activity at the two weeks purging,which indicated that timely purging could improve the activities of antioxidant enzymes in A.nobilis serum.Therefore,the optimal purging time is helpful to improve the quality and nutritional value of A.nobilis and reduce capture stress for transportation.