肉桂精油复合微乳体系构建及其在酱牛肉加工中的应用

Fabrication of Cinnamon Essential Oil-based Composite Microemulsions and Their Applications in Braised Beef

摘要:

本文分别以0.5%乳酸链球菌素、0.5%植酸钠或0.5% ε-聚赖氨酸盐酸盐为水相,以吐温80、乙醇分别为乳化剂和助乳化剂，研究o/w型肉桂精油复合微乳体系的相行为规律,测定微乳体系的pH、粘度、电导率和粒径等物理表征，筛选水溶性稳定的微乳配方，研究微乳体系对大肠杆菌和金黄色葡萄球菌的最低抑菌浓度（MIC），并将分别含有不同防腐剂的复合微乳液处理酱牛肉，通过挥发性盐基氮和微生物特征来观察微乳液对酱牛肉在冷藏期间的防腐保鲜效果。结果表明：三种食品防腐剂对微乳体系的水溶性能没有显著影响，防腐剂种类对微乳体系的pH、电导率等指标有影响；配方MEP（含ε-聚赖氨酸盐酸盐）对大肠杆菌的MIC最低，为16 mg/mL。而配方MEP与MEN（含乳酸链球菌素）对金黄色葡萄球菌的MIC最低，均为8 mg/mL；微乳液处理能延缓酱牛肉的腐败变质，能够降低冷藏期间酱牛肉中挥发性盐基氮含量，并可明显减慢细菌总数和大肠菌群总数的增长。

Abstract:

To study the phase behavior of an oil-in-water cinnamon essential oil-based microemulsion system, Tween -80 and ethanol were selected as the surfactant and co-surfactant, respectively, and 0.5% nisin, 0.5% sodium phytate, or 0.5% ε-poly-L-lysine?hydrochloride (HCl) was used as the aqueous phase. The pH value, viscosity, electric conductivity, particle size, and other physical properties of the microemulsion system were analyzed, the most stable water-soluble microemulsion formulations were optimized, and the minimum inhibitory concentrations (MICs) of the microemulsions for Escherichia coli and Staphylococcus aureus were determined. Braised beef samples were treated with composite microemulsions containing different preservatives, and the performances of the microemulsions on the preservation of braised beef during cold storage based on total volatile base nitrogen and microbial characteristics were analyzed. The results showed that the three food preservatives had no significant influence on the water solubility of the microemulsionss but affected the pH, electric conductivity, etc. The microemulsions containing ε-poly-L-lysine?HCl (MEP) had the lowest MIC for E. coli (16 mg/ml), and MEP and the microemulsions containing nisin showed the lowest MIC for S. aureus (8 mg/ml). Treatment with the microemulsions delayed beef spoilage, reduced the content of total volatile basic nitrogen in the braised beef during cold storage, and significantly lowered the growth of total bacterial count and coliform bacteria.