摘要：近年来微乳液体系在食品工业中的应用已经越来越广泛和成熟，精油微乳液已经成为国内外研究的热门课题。致力于天然防腐剂的开发与研究，能够提高薄荷精油的实用性能。本文利用GC-MS对欧薄荷精油成分进行了分析，通过拟三元相图，构建了以欧薄荷精油为油相的食品级微乳体系，研究了不同表面活性剂、助表面活性剂以及盐对微乳体系相行为的影响。选择并构建了两种以欧薄荷精油为油相，乙醇作为助表面活性剂，吐温80作为表面活性剂的食品级U型微乳液，测定其pH、密度、粒径等理化指标。并研究欧薄荷精油微乳液在培养基中对大肠杆菌、金黄色葡萄球菌、酿酒酵母的最低抑菌浓度（MIC）和最低杀菌浓度（MBC）。20588
主要实验结果如下：
通过加入表面活性剂、助表面活性剂以及盐溶液，可以提高欧薄荷精油微乳液的增溶效果；不同表面活性剂对微乳体系的增溶能力不同，其中吐温80最佳。助表面活性剂的增溶效果乙醇最佳。盐溶液作为水相的最佳复配浓度和比例为5%D异抗坏血酸钠：5%山梨酸钾=1:1；选取两种微乳体系的配方：配方一即欧薄荷精油：乙醇：吐温80：5%D异抗坏血酸钠：5%山梨酸钾=2.8：2.8：8.4：3：3，配方二欧薄荷精油：乙醇：吐温80：5%D异抗坏血酸钠：5%山梨酸钾=1.8：1.8：8.4：4：4，微乳液的平均粒径分别为61.43 nm（配方1）和96.88 nm（配方2）；平均密度分别为0.954 g/ml（配方1）和0.987 g/ml（配方2）；配方2的pH的变化更为稳定。抑菌试验结果显示配方一在抑菌效果更为显著，37 °C 220 r 培养24 h，其对大肠杆菌和金黄色葡萄球菌的MIC分别为32 μL/mL和32 μL/mL，MBC分别为64 μL/mL和64 μL/mL。30 °C 220 r 培养24 h对酿酒酵母菌的MIC和MFC分别为64 μL/mL和128 μL/mL。
毕业论文关键词：欧薄荷精油；微乳液；三元相图；抑菌；
Construction and antimicrobial of European peppermint essential oil micro-emulsion system
ABSTRACT:  In recent years, application of micro-emulsion system in the food industry has become increasingly widespread and sophisticated.Oil micro-emulsion has become a hot topic of research both in China and abroad.Committed to the development and research of natural preservative which can improve the practical performance.In this paper,we have used GC-MS for analyzing peppermint essential oil components and have used ternary phase diagrams construct peppermint essential oil as oil phase in food grade micro-emulsion system.The effects of different surfactants, co-surfactants and salt on the phase behavior have been elucidated.Select and build two types of U-shaped food grade micro-emulsion system with peppermint oil as oil phase,ethanol as a co-surfactant and Tween80 as a surfactant.Measured the pH, particle size and other physical and chemical indicators.Determined the minimum inhibitory concentration (MIC) and minimum bactericidal concentration(MBC) on Escherichia coli, Staphylococcus aureus and Saccharomyces cerevisiae.
The main results are as follows:
By adding a surfactant, co-surfactant and the salt solution,the food-grade micro-emulsion system can be formed effectively.Different surfactants have different effects on micro-emulsion system,the best of which is Tween 80.And the best co-surfactant was ethanol.The best combination of salt solution concentrations as aqueous phase was 5% D-sodium erythorbate and 5% potassium sorbate,ratios was one to one.Selected two recipes micro-emulsion system.Selected peppermint oil:ethanol:Tween80:5% D-sodium erythorbate:5% potassium sorbate= 2.8:2.8:8.4:3:3 as Formula 1.Selected the ratios 1.8:1.8:8.4:4:4 as Formula 2.The average particle size of the micro-emulsion were 61.43 nm (Formula1) and 96.88 nm (Formula2).The average density were 0.954 g/ml (Formula1) and 0.987 g/ml (Formula2).The change of pH of Formulation 2 was more stable.Antibacterial test resulted Formula1 had a significant inhibitory effect.37 °C 220 r micro-emulsion in NA medium within 24h showed MIC on E.coli and S.aureus was 32 μl/ml and 32 μl/ml. MBC was 64 μl/ml and 64 μl/ml. 30 °C 220 r MIC and MFC on S.cerevisiae were 64 μl/ml and 128 μl/ml. 欧薄荷精油微乳体系的构建及其抑菌研究:http://www.751com.cn/shiping/lunwen_12425.html