蒸制和炸制对海鲈鱼肉体外消化特性的影响

Effects of steaming and frying on digestive characteristics of Perca fluviatilis muscle in vitro

为研究蒸制和炸制对海鲈鱼肉体外消化特性的影响,利用胃蛋白酶-胰蛋白酶体外模拟消化法,通过测定蛋白消化率和粒径的变化结合激光共聚焦显微镜观察研究蒸制和炸制样品体外消化特性的差异,同时对其消化产物的抗氧化特性进行初步评价。结果表明,蒸制和炸制处理使海鲈鱼肉体外模拟消化后的蛋白消化率显著提高(P<0.05),消化液中蛋白聚集体的粒径显著降低(P<0.05),其中消化前60 min内蒸制样品的消化速率较快,而消化后期炸制样品的消化速率较快;随消化时间的延长,消化液中的蛋白质聚集体逐渐被分解成细小的颗粒。体外模拟消化会促进脂质的氧化,各组样品消化液的硫代巴比妥酸值随消化时间的延长先升高后又显著降低(P<0.05),其中炸制样品的脂肪氧化程度较高;消化液的Fe^2+螯合能力随消化时间的延长明显提高,其中蒸制样品在消化终点时的Fe^2+螯合能力最大,其抗氧化性较强。

Pepsin and trypsin in vitro simulated digestion method was adopted to investigate the effects of steaming and frying on the in vitro digestion characteristics of Perca fluviatilis muscle.The differences in the in vitro digestion characteristics of steamed and fried samples were studied by determining the changes of protein digestibility and particle size in combination with the confocal laser scanning microscope(CLSM).At the same time,the antioxidant properties of the digested products were preliminarily evaluated.The results showed that the protein digestibility of Perca fluviatilis muscle was significantly increased after steaming and frying treatment(P<0.05),and the particle size of protein aggregates in the digestive juice was significantly reduced(P<0.05).Meanwhile,the digestion rate of the steamed sample was faster within 60 min of digestion,while that of the fried sample was faster in the late digestion period.With the prolongation of digestion time,the protein aggregates in the digestive juice were gradually decomposed into fine particles.Simulated digestion in vitro promoted the oxidation of lipids,and the TBA value of the digestive juice of each group first increased and then decreased significantly with the extension of digestion time(P<0.05),and the lipid oxidation degree of the fried sample was higher.The Fe 2+chelating ability of the digestive juice increased significantly with the extension of digestion time,among which the steamed sample had theargest Fe 2+chelating ability at the end of digestion and its antioxidant activity was relatively strong.