没食子酸对豆腐柴果胶可食膜的影响研究

文章研究没食子酸(gallic acid, GA)对豆腐柴果胶可食膜的影响, 测试添加 GA 后可食膜的理化性质、微观结构和生物活性。结果表明, 添加 GA 使可食膜的颜色加深, 厚度和不透明度增加, 胶链与水分子的相互作用增强, 水分质量分数、水溶性和溶胀率升高。由于 GA 分子渗透到胶链中, 所得薄膜具有较低的拉伸强度、较高的断裂伸长率以及较强的抗氧化和抗菌性能。尤其是加入 1% GA 后, 豆腐柴果胶可食膜显示出优良的机械特性和膜结构, 其拉伸强度为 $ (173.60 \pm 2.21) $ MPa, 断裂伸长率达到 $ 4.83 \pm 0.23\% $. 添加 1% GA 的可食膜也具有良好的抗氧化活性, 其 DPPH 自由基清除率为 $ 86.55 \pm 0.63\% $. 同时, 可食膜的抗菌性能显著提高 $ (P < 0.05) $. 研究表明, 豆腐柴果胶可用于制备新型生物活性可食膜, 为充分利用我国丰富的豆腐柴资源提供了参考.

In this paper, the effect of gallic acid(GA) on the edible films of pectin extracted from *Pemna microphylla* Turcz. was investigated by examining the physicochemical properties, microstructure and biological activities of the edible films added with different concentrations of GA. The results indicated that the addition of GA deepened the color of the edible films, enhanced their thickness and opacity, boosted the interaction between the gum chains and water molecules and increased the moisture content, water solubility and swelling rate. Due to the penetration of GA molecules to the chains, the resultant films had lower tensile strength, higher elongation at break and stronger antioxidant and antibacterial properties. Especially when 1% GA was added, the edible films exhibited excellent mechanical properties and film structure. The tensile strength was $ (173.60\pm2.21) $ MPa, and the elongation at break reached $ 4.83\%\pm0.23\% $. The composite films also possessed satisfactory antioxidant activities, with a DPPH free radical scavenging rate of $ 86.55\%\pm0.63\% $. Simultaneously, the antibacterial properties of the edible films were significantly improved (P<0.05). Thus, the current study suggests that the pectin extracted from *Pemna microphylla* Turcz. can be used to fabricate novel bioactive edible films and provide reference for realizing the full utilization of *Pemna microphylla* Turcz. resources in China.