Isolation And Identificantion Of Antifungal Components Of Antifungal Lactic Acid Bacteria And Its Application In Cheese Preservation

In recent years,with the development of China's food industry,cheese products are not only favored by consumers,but also more and more used in food and beverage industry and baking and other food processing industry.In the context of the increasing demand for preservative-free food in the food industry,it is a better choice to replace or reduce the use of chemical preservatives with biological protectant.In this study,the inhibitory effect of acellular supernatant of 9 strains of lactic acid bacteria on 4 strains of fungi(Aspergillus Niger,Aspergillus flavus,Pichia pastoris and Kluyveromyces marxianu)was investigated by microdilution method,and one strain with significant antibacterial ability was screened out: Lactobacillus rhamnosus N14(P<0.05),the cell-free supernatant of the strain had significant antibacterial effect on the suspension of four strains,and the minimum inhibitory concentrations(MIC values)were 62.5 mg/m L,62.5 mg/m L,250 mg/m L and 125 mg/m L,respectively.In addition,through the separation and identification of the cell-free supernatant of N14,the main antibacterial substances were found to be lactic acid,citric acid,3-phenyllactic acid and linoleic acid,etc.Finally,N14 dry powder was mixed with commercial starter to prepare cheese,so that cheese had certain antifungal effect.The purpose of this study was to apply antifungal lactic acid bacteria to cheese preservation,so as to provide theoretical basis and application reference for the utilization of antifungal lactic acid bacteria and its active substances,and at the same time,to provide new ideas and ingredients for the fermentation and preservation of cheese.