黄芩茎叶没食子酸-KGM复合保鲜膜在鸡蛋保鲜中的应用研究

为延长鸡蛋货架期，以商洛黄芩茎叶没食子酸作为研究对象制备复合保鲜膜。本研究采用超声辅助乙醇浸提法从黄芩茎叶中提取没食子酸，提取量为203.35 mg/g；对提取出的没食子酸浓缩液进行抑菌实验，研究没食子酸对金黄色葡萄球菌、大肠杆菌、肠炎沙门菌的抑菌能力。结果表明：抑菌效果为大肠杆菌<金黄色葡萄球菌<肠炎沙门菌。在分别探讨没食子酸、魔芋葡甘聚糖、壳聚糖和柠檬酸保鲜作用的单因素试验基础上，采用响应面法，以哈夫单位为响应值对复合保鲜配方进行优化。结果表明：没食子酸1.85%、魔芋葡甘聚糖1.24%、壳聚糖1.96%、柠檬酸3%复配用以制备复合保鲜膜为最佳配比。将此配方制成的复合保鲜膜均匀涂抹在鸡蛋上，在37℃下鸡蛋可以保存15天，鸡蛋的哈夫单位可达到74.86±2.61。所制备的复合保鲜膜绿色、安全，可为鸡蛋的保鲜提供技术参考。

Application of Gallic Acid-KGM Composite Fresh-keeping Film from Stems and Leaves of Scutellaria baicalensis Georgi to Egg Preservation

In order to prolong the shelf life of eggs, composite fresh-keeping film was prepared with gallic acid from the stems and leaves of Scutellaria baicalensis Georgi in Shangluo as the research object. In this study, gallic acid was extracted from the stems and leaves of Scutellaria baicalensis Georgi by ultrasonic-assisted ethanol extraction, and the extraction amount was 203.35 mg/g; the bacteriostasis experiment was carried out on the extracted concentrated solution of gallic acid to study the bacteriostatic ability of gallic acid against Staphylococcus aureus, Escherichia coli and Salmonella enteritidis. The results showed that the bacteriostatic effect was on Escherichia coli< Staphylococcus aureus< Salmonella enteritidis. Based on the single factor experiment of the preservation effect of gallic acid, konjac glucomannan, chitosan and citric acid, the response surface methodology was used to optimize the compound preservation formula with Haugh unit as the response value. The results showed that the best ratio of gallic acid, konjac glucomannan, chitosan and citric acid was 1.85%, 1.24%, 1.96% and 3%, respectively. In summary, the Haugh unit of egg can reach 74.86±2.61 when the composite fresh-keeping film made from this formula is evenly spread on the egg which will be stored at 37℃ for 15 days. The composite fresh-keeping film prepared is environment-friendly and safe, which can provide technical reference for egg preservation.