干酪可食性涂膜保鲜剂配比的研究

Study on presciption of coating edible preservative for cheese

为研究开发可食用干酪保鲜剂,以酪蛋白酸钠为基材,添加天然抑菌材料构成基液,在此基础上分别对单一添加纳他霉素和溶菌酶的基液进行了抑菌效果的对比,供试菌为大肠杆菌、金黄色葡萄球菌、假单胞菌、酵母菌和霉菌。同时对混合添加纳他霉素和溶菌酶的基液的抑菌效果进行了研究并对其配比进行优化。结果表明:单一添加纳他霉素的抑菌保鲜液对霉菌和酵母菌的抑菌性随其用量增加而增强,而且不同用量之间均存在显著差异(p<0.05),对金黄色葡萄球菌、假单胞菌的抑菌效果呈先增加后减小,而对大肠杆菌的抑菌作用在不同用量之间不存在显著差异(p>0.05);单一添加溶菌酶的抑菌保鲜液对酵母菌的抑制作用较强(p<0.05),对其它菌种抑菌圈小于12 mm。运用响应面优化法以吸光值增量为指标对壳聚糖、那他霉素、溶菌酶混合添加的的配比进行优化,结果表明:那他霉素0.07 g/100 m L基液、溶菌酶1.0 g/100 m L基液,所得吸光值增量达到最小值为1.225,且壳聚糖与那他霉素和壳聚糖与溶菌酶之间存在显著的交互作用(p<0.05),那他霉素和溶菌酶交互作用不显著(p>0.05),并在此配比下的抑菌圈直径分别是大肠杆菌13.67 mm,金黄色葡萄球菌14.33 mm,假单胞菌15.66 mm,酵母菌18.00 mm和霉菌17.76 mm。

To study and develop an edible preservation film,the antibacterial property of the base liquid mixture adding the inhibiting components of natamycin and lysozyme were tested. The base liquid was composed of caseinate sodium,and chitosan and glycerol.The test bacteria were E.coil, Staphylococcus aureus, Pseudomonas fluorescens,yeast and mold.The result showed that the antibacterial effect of natamycin on mold and yeast was enhanced with the increase of its dosage, and there were significant differences between different dosage （ p 〈 0.05）.lnihibiting effect of natamycin on Staphylococcus aureus, Pseudomonas fluorescens was first increased and then decreased and the effect on Ecoli showed no significant difference among different amount（ p 〉 0.05）.The inhibitory effect of lysozyme had a significant effect on yeast（p 〈0.05）, but the inhibition zone of other bacteria were less than 12 mm.Response surface analysis was employed to optimize parameters of the prescription of the base liquid with blend of natamycin and lysozyme.The evaluating index was the increment of absorbance.The results revealed that the optimum additive amount of natamycin and lysozyme was 0.07 g/100 mL base liquid and 1 g/100 mL base liquid.At this dose,the absorbance increment of the base liquid reached a minimum value.The result also showed that there were significant interaction effects between chitosan and natamycin, as well as between chitosan and lysozyme（ p 〈 0.05）, wheras the interaction effects between natamycin and lysozyme was not significant（ p 〉0.05）, and the diameter of the inhibition zone of E. coil, Staphylococcus aureus, Pseudomonas, yeast and mold were 13.67,14.33,15.66,18.00,17.76 mm in this ratio respectively.