Microbial Diagnosis of Some Mayonnaise Samples and Study the Effect of Growth Factors on Three Local Strains of Bacteria Escherichia coli

Abstract

The study included the investigation of bacterial species that present in several samples of commercial mayonnaise and a sample of mayonnaise manually made as well as the develop ment of three isolates of local bacteria Escherichia coli in one of the commercial samples and investigate the effect of growth factors of temperature and pH value on the growth of these three isolates o f the bacteria, the results showed that commercial mayonnaise is free from most forms of pathogenic bacteria, based on culture the samples onthe special media, and for the sample processed manually we have noted the presence of Staphylococcus aureus and St. albus bacteria and the fungi Aspergillus niger. As for the effect of growth factors, we have seen reduced in the rate of growth of isolates pathogenesis of the bacteria E.coli as we change temperature and pHusing several temperatures 22 C, 35 C and 43 C and values of PH are 3.8, 4.4 and 5.0.