没食子酸改性酶解-糖基化胶原蛋白-壳聚糖复合膜的制备及表征

Preparation and Characterization of Gallic Acid Modified Enzymolysis Glycosylated Collagen Film

为改善猪皮胶原蛋白(PC)可食性膜的机械性能、耐热性和疏水性较差等问题,本研究将猪皮胶原蛋白进行酶解-糖基化改性处理制备出糖基化胶原蛋白(HG-PC)可食性膜,然后通过没食子酸(GA)对糖基化胶原蛋白膜改性制备复合膜(GA-HG-PC膜)。对比分析PC膜、HG-PC膜和GA-HG-PC膜的机械性能、持水性、水蒸气透过率、颜色、热稳定性及抗氧化性,并通过傅里叶变换红外光谱和扫描电子显微镜表征薄膜结构、纳米粒度及Zeta电位仪测定膜液的粒径和电位。结果表明,GA-HG-PC膜的抗拉强度、断裂伸长率分别较PC膜和HG-PC膜提高121.57%、19.00个百分点和91.52%、14.16个百分点;其水蒸气透过率较PC膜和HG-PC膜下降,耐水性显著改善(P<0.05);GA-HG-PC膜的颜色比PC膜和HG-PC膜更深,透明度下降,热稳定性提高;此外,GA-HG-PC膜的内部结构更加稳定,氢键作用力较强,成膜溶液稳定性提高,其1,1-二苯基-2-苦基肼(DPPH)自由基清除率分别较HG-PC膜和PC膜增加10.49和18.26个百分点(P<0.05)。本研究可为改善PC膜的功能特性提供新思路,拓展其在果蔬、水产品、肉制品及烘焙食品等领域的应用,对开发新型可食性蛋白膜具有一定意义。

To address the issues of poor mechanical properties,heat resistance and hydrophobicity of the edible film of pig collagen(PC),this study prepared glucose complex hydrolyzed PC by enzymolysis and glycosylation modification methods.Gallic acid(GA)was used to modify glycosylated collagen film to prepare a composite film(GA-HG-PC film).The mechanical properties,water retention,water vapor transmittance,color,thermal stability and oxidation resistance of PC film,HG-PC film and GA-HG-PC film were compared and studied.The structural characterization of the three films was performed using Fourier transform infrared spectroscopy and scanning electron microscope,and the particle size and potential of the film liquid were measured by nanoparticle.Results showed that the tensile strength and elongation at break of GA-HG-PC films were 121.57%,19.00 percentage points and 91.52%,14.16 percentage points higher than these of PC film and HG-PC film,respectively.The water resistance and water vapor transmittance of the film were significantly improved compared with PC film and HG-PC film(P<0.05).The color of GA-HG-PC film was darker than that of PC film and HG-PC film,while the transparency was decreased and the thermal stability was improved.Besides,the internal structure of GA-HG-PC film was more stable than other films,with stronger hydrogen bond force and the stability of the film forming solution was improved.The 1,1-diphenly-2-picrylhydrazyl free radical clearance rate increased by 10.49 percentage points and 18.26 percentage points compared with PC film and HG-PC film(P<0.05).This study could provide a new idea for improving the functional properties of PC film,expanding its application in fruits and vegetables,aquatic products,meat products and baked goods,and have a certain significance for the development of new edible protein films.