Abstract: Along with the food industry's rapid development, more and more people come to realize the importance of food preservative gradually,and we pay more attention to the research and development of food preservative.However, most synthetic preservatives do harm to the people’s health, so that they have been limited the scope of their application. Compared to the synthetic preservatives , natural preservatives have more advantages.Such as the efficient antibacterial, safe and non-toxic, water-soluble, and good thermal stability, egg .So the natural preservatives have been used widly in the food industry . In order to study the effect control of microorganisms by Nisin、Natamycin and ε - polylysine,the three composite of natural preservatives in the cakes,as a result,we can know the most efficient of composite preservation.In this experiment ,I adopt designing the three factors and three levels of orthogonal experiment. Through accessing the various levels of the composition preservatives in the cakes, and then these cakes are cultivated on the constant temperature and humidity conditions of 37 ° C and 25 ° C to 28 ° C respectively.After 3 days,5days and 7days , they need the total number of bacteria colonies and the total number of mildew colonies measured respectively. At last ,through analysing these datas, I can find the most efficient of composite preservation in the cakes.This experimental results is : the most efficient of composite preservation in the cakes is : the concentration of Nisin is 200 mg / kg, the concentration of Natamycin is 300 mg / kg, and the concentration of ε - polylysine is 100 mg / kg.
