普鲁兰多糖/壳聚糖/黄原胶/胶原蛋白复合膜的制备及保鲜效果研究

Preparation and preservation effect of pullulan polysaccharide/chitosan/xanthan gum/collagen composite coating

为延长大口黑鲈鱼货架期,将3 g/100 mL的鱼皮胶原蛋白溶液添加到普鲁兰多糖/羧甲基壳聚糖/黄原胶溶液中,再结合超声工艺制备成可食性复合抑菌涂膜剂。通过抗拉伸强度、断裂伸长率、溶胀率、膜厚度、透光率和水蒸气透过率的测定,研究各成膜剂质量比、膜液质量浓度和超声时间等因素对复合膜性能的影响。结果表明,m(普鲁兰多糖)∶m(羧甲基壳聚糖)∶m(黄原胶)=2∶2∶1,成膜剂质量浓度为1.4 g/100 mL,240 W超声处理15 min,此时普鲁兰多糖复合膜的性能表现最佳。在大口黑鲈鱼保鲜实验中,-2℃存放10 d后经涂膜处理的鱼肉其菌落总数(total viable count,TVC)与挥发性盐基氮(total volatile base nitrogen,TVB-N)值仍处于一级鲜度;K值属于极鲜品;pH值仍低于规定限值;肌动球蛋白、总巯基、Ca^(2+)-ATP酶活性和持水力分别下降了12.05%、23.75%、25.35%和7.81%,各项指标均优于对照组。综上所述,普鲁兰多糖/壳聚糖/黄原胶/胶原蛋白复合膜具有良好的保鲜效果。

To prolong the shelf life of Micropterus salmoides,3 g/100 mL fish skin collagen solution was added to pullulan polysaccharide/carboxymethyl chitosan/xanthan gum solution,and then combined with the ultrasonic process to prepare edible composite antibacterial coating agent.By measuring tensile strength,elongation at break,swelling rate,film thickness,light transmittance,and water vapor transmittance,the influences of mass ratio of the film-forming agent,the mass concentration of film liquid,and ultrasonic time on the properties of composite film were studied.Results showed that the mass ratio of pullulan polysaccharide,carboxymethyl chitosan,and xanthan gum was 2∶2∶1,the mass concentration of the film-forming agent was 1.4 g/100 mL,and the performance of pullulan polysaccharide composite film was the best when treated with 240 W ultrasound for 15 min.In the experiment of preservation of M.salmoides,the total viable count and total volatile base nitrogen values of the coated fish were still rated the first order of freshness after being stored at-2 ℃ for 10 d and the K value belonged to the freshest products.The pH value was still below the specified limit.Actomyosin,total sulfhydryl,Ca^(2+)-ATPase activity,and water retention were decreased by 12.05%,23.75%,25.35%,and 7.81%,respectively,and all indexes were better than those of the control group.In conclusion,pullulan polysaccharide/chitosan/xanthan gum/collagen composite coating has a good preservation effect.