褐藻酸钠裂解物提高凡纳滨对虾保水性机理的研究

Mechanism of enhancing the water-holding capacity of white leg shrimp by alginate oligosacchrides

采用化学氧化法制备了分子量大于6 ku的褐藻胶裂解物HDX-A,研究其提高凡纳滨对虾保水性的机理。结果表明,经1%的HDX-A溶液浸泡1 h凡纳滨对虾虾仁增重率为14.6%,且经冻藏20 d后解冻损失率和蒸煮损失率均低于水浸泡和3%复合磷酸盐处理。冻藏后,HDX-A处理组ATPase活性降低了40%,显著低于未处理和水处理样品变化量(P<0.01),与3%复合磷酸盐相比差异不显著(P>0.05),而流变性特征与新鲜样品比较除破断力降低外均无显著差异(P>0.05)。组织学结果显示,HDX-A能影响冻藏过程中冰晶的生成和生长,单位面积横切面内孔洞的数目较多且较小,其中面积小于100μm2的孔洞比例约为74.5%,面积为100～2 500μm2孔洞的比例约为25.5%,没有出现超大孔洞。

The product of HDX-A with a molecular weight over 6 000 ku was made from sodium alginate obtained by H2O2.And the mechanism of the HDX-A enhancing the water-holding capacity of white leg shrimp was studied.The results showed that the weight of white leg shrimp significantly increased by 14.6 percent after being marinated in 1 percent solution for 1 hour.Also the drip loss and the cooking loss were lower than those of the control and phosphate compound treatments after being frozen 20 days.Although the ATPase activity of the HDX-A treatment reduced by 40 percent,it was lower than the untreated sample and the control.But there was no difference between the HDX-A treatment and the compound phosphate treatment in the ATPase activity.The physical characteristics of the HDX-A treatment sample were similar to the fresh sample except that the break strength became small.The result of the histology showed that the building and growth of the ice were affected by HDX-A during frozen storage.The holes were smaller and more in unit area than those of the control.The ratio of the hole whose area was less than 100 μm2 was about 74.5 percent.The percentage of the other holes whose area were between 100-2 500 μm2 was 25.5.There was no super big hole in the white leg shrimp muscle.