江永香柚皮水溶性抑菌成分的提取及其在6类食品中的应用

Extraction of Water-soluble Antimicrobial Molecules from Peels of Citrus Grandis and Its Application in 6 Kinds of Food

研究江永香柚皮水溶性抑菌成分的提取及其在食品中的抑菌作用,为进一步开发利用奠定基础。以柚皮水提物对培养基中金黄色葡萄球菌抑菌圈大小为指标,优化了江永香柚皮水溶性抑菌成分的提取工艺,并初步探讨其水提物对牛奶、橙汁、黄豆酱、酸梅汤、食用油和奶茶中金黄色葡萄球菌的抑制作用。结果表明,江永香柚皮水溶性抑菌成分的最适提取工艺为:超声时间28 min、超声温度39 ℃、料液比为1:15 g/mL、粒径为40目,最适提取条件下提取物对金黄色葡萄球菌的抑菌圈大小为14.99 mm。抑菌试验表明,在盐水体系中以3%体积分数的江永香柚皮水提物杀菌效果最好,处理25 min后金黄色葡萄球菌菌落总数减少了约5.5个数量级,而在6种不同的液体食品中25 min内都可使体系中接种的S.aureus菌落总数降低1.3个数量级以上。江永香柚皮水提物有望开发成天然食品防腐剂。

In order to provide the technological and theoretical basis for development and utilization from peels of citrus grandis,the extraction conditions and inhibitory effect of water-soluble antimicrobial molecules from peels of citrus grandis were investigated in this study.Using the size of inhibition zone of aqueous extract from peels of citrus grandis against Staphylococcus aureus in the culture medium as the indicator,the extraction process of water-soluble antimicrobial molecules in peels of citrus grandis in Jiangyong was optimized,and the sterilization effect of the water-soluble antimicrobial molecules against Staphylococcus aureus in milk,orange juice,soybean paste,syrup of plum,edible oil and milk tea was explored.The results show that the optimal extraction conditions of water-soluble antimicrobial molecules in peels of citrus grandis in Jiangyong were as follows:28 min ultrasonic treatment time;39 ℃ extraction temperature;1:15 g/mL solid/liquid ratio and 40 mesh particle size.The size of the inhibition zone of extracts against Staphylococcus aureus under the these optimal extraction conditions was 14.99 mm.The best inhibition effects of the extracted antimicrobial molecules against Staphylococcus aureus was achieved at the concentration of 3%(volume) in NaCl-water system,and S.aureus reduced by about 5.5 orders of magnitude after 25 min.of treatment.Under the above conditions,the total number of colonies of S.aureus inoculated in 6 different kinds of liquid food could be reduced by more than 1.3 orders of magnitude.The aqueous extract from peels of citrus grandis in Jiangyong can be expected to be developed into a natural food preservative.