结冷胶-沙蒿胶-蓝莓花青素可食性膜的制备及其性能分析

利用蓝莓花青素对pH值的指示作用制备智能包装膜,以期解决食品保鲜过程中新鲜度的检测难题。以结冷胶、沙蒿胶和蓝莓花青素为主要原料,采用流延法制备智能指示膜,研究膜的色差、机械性能、水溶性、水蒸气透过率以及微观结构等分析其性能。结果表明,红外扫描和电镜分析表明沙蒿胶与结冷胶及蓝莓花青素之间具有良好的相容性;沙蒿胶能够提高结冷胶/沙蒿胶-蓝莓花青素膜的厚度、膜的断裂延伸率、水蒸气透过率,降低膜的抗拉伸强度和水溶性;结冷胶/沙蒿胶复配比8∶2(质量比)时,花青素膜的断裂延伸率最大为47.36%,水蒸气透过率为7.643×10^-6 g·m/(d·Pa·m^2),抗拉强度22.08 MPa,复配比4∶6(质量比)的膜厚度达到0.079 mm;复合膜对pH值的指示作用显著,可作为pH指示膜。本研究为新型食品保鲜智能指示膜的应用提供理论基础。

Preparation and characteristics analysis of gellan gum-Artemisia sphaerocephala Krasch gum-blueberry anthocyanin edible film

A new sensor film of blueberry anthocyanin,which could indicate pH value changes,was prepared for food freshness detection in the process of food preservation.The intelligent packaging film of gellan gum/Artemisia sphaerocephala Krasch gum-blueberry anthocyanin was prepared by casting method.The color difference,mechanical properties,water solubility,water vapor permeability and microstructure of the film were investigated.The results of Fourier infrared spectroscopy scanning(FTIR)and scanning electron microscopy(SEM)showed that there was good compatibility between Artemisia sphaerocephala Krasch gum with gellan gum and blueberry anthocyanin.The thickness,elongation at break(EAB)and water vapor permeability(WVP)of film enhanced with addition of Artemisia sphaerocephala Krasch gum,while tensile strength(TS)and water solubility of the film reduced.EAB of the anthocyanin film with a compounding ratio of 8∶2 reached 47.36%,WVP 7.643×10^-6 g·m/(d·Pa·m^2),TS at 22.08 MPa.The film thickness of film(4∶6)reached 0.079 mm respectively.Furthermore,there were significant color response of the film on the pH conditions and the colors of the film displayed from red to purple as pH condition changed.Therefore,the gellan gum/Artemisia sphaerocephala Krasch gum-blueberry anthocyanin edible film could be used as a novel food preservation pH intelligent indicator film,and these results indicate a theoretical basis of intelligent indicator film for food preservation.