许多具有抗氧化和抗菌活性的亲水性可食性涂层材料通常对果蔬蜡质疏水表面附着力较弱,严重限制了可食性涂层在食品保鲜中的应用。在这项工作中,表没食子儿茶素没食子酸酯(EGCG)通过自由基介导的反应与果胶接枝,试图通过EGCG独特的邻苯三酚结构增强果胶在水果和蔬菜疏水表面的粘附。研究了EGCG与不同类型果胶共价接枝对其理化性质、抗氧化活性和抗菌活性的影响。结果发现,低甲氧基果胶(LMP)接枝EGCG(LMP-EGCG)涂层可显着降低减重,降低葡萄酚含量和多酚氧化酶活性(p < 0.01),抑制葡萄成熟后脂质氧化和微生物生长(p < 0.01)。最后,利用接触角和水中溶解度来评价LMP-EGCG在葡萄表面的粘附性能,结果表明EGCG的共价接枝显着增强了果胶涂层在葡萄表面的润湿和粘附性能。葡萄皮。综上所述,这些结果表明EGCG的共价接枝赋予了果胶可食用涂层在果蔬疏水表面的粘附能力,在果蔬保鲜领域具有广泛的应用潜力。抑制脂质氧化,抑制葡萄成熟后微生物的生长(p < 0.01)。最后,利用接触角和水中溶解度来评价LMP-EGCG在葡萄表面的粘附性能,结果表明EGCG的共价接枝显着增强了果胶涂层在葡萄表面的润湿和粘附性能。葡萄皮。综上所述,这些结果表明EGCG的共价接枝赋予了果胶可食用涂层在果蔬疏水表面的粘附能力,在果蔬保鲜领域具有广泛的应用潜力。抑制脂质氧化,抑制葡萄成熟后微生物的生长(p < 0.01)。最后,利用接触角和水中溶解度来评价LMP-EGCG在葡萄表面的粘附性能,结果表明EGCG的共价接枝显着增强了果胶涂层在葡萄表面的润湿和粘附性能。葡萄皮。综上所述,这些结果表明EGCG的共价接枝赋予了果胶可食用涂层在果蔬疏水表面的粘附能力,在果蔬保鲜领域具有广泛的应用潜力。采用接触角和水中溶解度评价LMP-EGCG在葡萄表面的附着性能,结果表明EGCG的共价接枝显着增强了葡萄皮表面果胶涂层的润湿和附着性能. 综上所述,这些结果表明EGCG的共价接枝赋予了果胶可食用涂层在果蔬疏水表面的粘附能力,在果蔬保鲜领域具有广泛的应用潜力。采用接触角和水中溶解度评价LMP-EGCG在葡萄表面的附着性能,结果表明EGCG的共价接枝显着增强了葡萄皮表面果胶涂层的润湿和附着性能. 综上所述,这些结果表明EGCG的共价接枝赋予了果胶可食用涂层在果蔬疏水表面的粘附能力,在果蔬保鲜领域具有广泛的应用潜力。
"点击查看英文标题和摘要"
Bioadhesive and antibacterial edible coating of EGCG-grafted pectin for improving the quality of grapes during storage
Many hydrophilic edible coating materials with antioxidant and antibacterial activities usually have weak adhesion on waxy hydrophobic surfaces of fruits and vegetables, seriously restricting the application of edible coating in food preservation. In this work, Epigallocatechin gallate (EGCG) was grafted with pectin by free radical mediated reaction to attempt to enhance the adhesion of pectin on the hydrophobic surface of fruits and vegetables through the unique pyrogallol structure of EGCG. The effects of covalent grafting of EGCG with different types of pectin on its physicochemical properties, antioxidant activity, and antibacterial activity were investigated. The results found that low methoxy pectin (LMP) grafted with EGCG (LMP-EGCG) coating could significantly reduce the weight loss, decrease phenol content and the activity of polyphenol oxidase of grapes (p < 0.01), and inhibit the lipid oxidation and inhibit the growth of microorganisms of grapes during post ripening (p < 0.01). Finally, the contact angle and solubility in water were used to evaluate the adhesion properties of LMP-EGCG on the surface of grapes, and the results showed that the covalent grafting of EGCG significantly enhanced the wetting and adhesion properties of pectin coatings on the surface of grape skin. Collectively, these results suggested that the covalent grafting of EGCG endowed the adhesion ability of edible coating of pectin on the hydrophobic surface of fruits and vegetables, which had broad application potential in the field of fruit and vegetable fresh-keeping.