捕后干露对3种贝类活品品质的影响

为明确经济养殖贝类捕后早期干露耐受性,选取活力良好的菲律宾蛤仔、长牡蛎和虾夷扇贝在4 ℃条件下进行8 d的无水贮藏,以闭壳肌pH、糖原、腺苷三磷酸(ATP)关联化合物、磷酸精氨酸的含量和奥品脱氢酶活性为指标,研究3种贝类的品质变化规律。试验结果表明,无水贮藏期间,菲律宾蛤仔pH无明显变化( P <0.05),而长牡蛎和虾夷扇贝pH分别由7.23和7.39降至6.88和6.80。3种贝的糖原含量均呈下降趋势。ATP在菲律宾蛤仔和长牡蛎初始含量仅为0.41、0.42 μmol/g,且贮藏过程无显著变化( P <0.05);在虾夷扇贝的初始含量为4.05 μmol/g,且随着贮藏时间延长急剧下降。虾夷扇贝和菲律宾蛤仔闭壳肌中章鱼碱脱氢酶活性最大,且随贮藏时间呈增加趋势。长牡蛎中alanopine脱氢酶和strombine脱氢酶起主要作用。结合主成分分析推定,长牡蛎、菲律宾蛤仔、虾夷扇贝对干露耐受时间分别是8、4、2 d。试验结果表明,在活贝捕后流通过程中应结合干露耐受性差异建立品种针对性的管理措施。

Effect of Post-Harvested Air Exposure on Quality of ThreeSpecies of Molluscs

In order to study the air exposure tolerance of cultured economically important molluscs in early post-harvest process, vigorous Manila clam Ruditapes philippinarum , Pacific oyster Crassostrea gigas and Yesso scallop Patinopecten yessoensi s were selected to put in the air exposure condition for 8 d in 4 ℃. The contents of glycogen, ATP related compounds and arginine phosphate, pH, and opine dehydrogenase activity in adductor muscle were detected to study the quality change in this process. The results showed that during the period of air-exposure storage, there was no significant change in the pH value of the molluscs ( P <0.05), while the pH values were decreased from 7.23 and 7.39 to 6.88 and 6.80 in oyster and scallop, respectively. The glycogen content of the three species of molluscs showed a decreasing trend. The initial contents of ATP in clam and oyster were only 0.41 and 0.42 μmol/g, with no significant change during storage ( P <0.05), while the initial content of ATP in scallop was 4.05 μmol/g, and decreased sharply with the extension of storage time. The activity of ODH was the highest in the adductor muscle of scallop and clam, and showed an increasing trend with the storage time, while ADH and SDH played bigger roles in oyster. Combined with principal component analysis, it was concluded that the tolerance time of oyster, clam and scallop in air exposure was 8 d, 4 d and 2 d, respectively. The findings indicated that the establishment of specific management measures should be combined with the difference of air exposure tolerance in the circulation process of post-harvested molluscs.