Evalution bacterial contamination of E. coli and Staphylococcous aureus in Cream Filled Pastries in West Tehran city

This descriptive cross-sectional study was performed to investigate the presence or absence of bacterial contamination caused by Escherichia coli and Staphylococcus aureus in creamy sweets in the west of Tehran. From 12 selected confectioneries in the west of Tehran, about 500 grams of creamy sweets equivalent to 3 pieces (solid food sample) (according to the instructions of the standard number of samples required in food sampling) were prepared using simple random sampling method. In this study, in order to isolate and identify Escherichia coli bacteria, lauryl sulfate tryptase culture medium was used. Due to gas production and turbidity observed in all samples (36 samples), EC Broth selective culture medium was used for complementary and confirmatory steps. peptone water culture medium was used for confirmatory tests of Escherichia coli and differentiation from other fecal coliforms, coaxial reagent was used for final confirmation. Isolation of Staphylococcus aureus bacteria was done using Cooked Meat enrichment medium and due to the production of spherical or oval or spindle colonies that were created in the depth of the medium in all samples, from Baird Parker Agar culture as The base was used for the second stage and in continuation of coagulase test to confirm Staphylococcus aureus bacteria from other staphylococci, rabbit citrate plasma was used for confirmatory tests. By reviewing the data, the rate of bacterial contamination caused by Staphylococcus aureus in 36 samples was equal to 25% and the rate of bacterial contamination due to Escherichia coli in 36 samples was equal to 5%.