普鲁兰多糖复合抑菌涂膜剂的制备及其对鸡蛋的保鲜效果

为延长鸡蛋货架期，以普鲁兰多糖为原料，通过添加甘油、阿拉伯树胶、溶菌酶和几丁质酶，并结合超声工艺制备成可食性复合涂膜保鲜剂。通过水蒸气透过系数和过氧化值的测定，研究各成膜剂质量比、膜液质量浓度、干燥时间、干燥温度和超声时间等因素对普鲁兰多糖复合膜性能的影响。结果表明：普鲁兰多糖、甘油、阿拉伯树胶质量比为3∶1∶2，成膜剂质量浓度为3.0～3.3 g/100 mL、干燥温度60 ℃、干燥时间90 min、150 W超声处理15 min、添加0.75 g/100 mL溶菌酶与几丁质酶（质量比1∶3），此时普鲁兰多糖复合涂膜剂的性能表现最佳，且能有效抑制大肠杆菌、金黄色葡萄球菌、沙门氏菌毛霉和曲霉的生长。在鸡蛋保鲜实验中，25 ℃存放28 d后涂膜组的鸡蛋质量损失率为6.16%，蛋黄指数为0.31，哈夫值下降至67.18，蛋清pH值由7.61上升至8.47，涂膜组鸡蛋品质仍维持在A级水平。综上，普鲁兰多糖复合抑菌涂膜剂具有良好的保鲜效果，能有效抑制腐败细菌和真菌生长。

Preparation and Application of Composite Antibacterial Pullulan Coating in the Preservation of Eggs

To extend the shelf life of eggs, an edible composite coating with antibacterial activity was made from pullulan with added glycerin, gum arabic, lysozyme and chitinase by ultrasonic treatment. The effects of film-forming agent composition and concentration, drying time, drying temperature and ultrasonic time on film performance were evaluated in terms of water vapor transmission coefficient and peroxide value. The results showed the film formed from a 3:1:2 mixture of pullulan, glycerol and gum arabic at a concentration of 3.0–3.3 g/100 mL with a 1:3 mixture of lysozyme and chitinase added at 0.75 g/100 mL subjected to ultrasonic treatment for 15 min at 150 W and drying at 60 ℃ for 90 min exhibited the best performance. The coating could effectively inhibit the growth of Escherichia coli, Staphylococcus aureus, Salmonella sp., Mucor sp. and Aspergillus sp.. After 28 d of storage at 25 ℃, the mass loss rate of eggs treated with the coating was 6.16%, the egg yolk index was 0.31, the Haugh unit decreased to 67.18 and the pH of egg white increased from 7.61 to 8.47; the quality of eggs in the experimental group remained at Level A. In summary, the composite pullulan coating can effectively inhibit the growth of spoilage bacteria and fungi and therefore have a good preservative effect.