Study of the microbial contamination rate of traditional ice cream products in Tehran, March 2008- March 2011

Since the process of traditional ice cream production enhances the chance of its microbial contamination, leading to a higher risk of foodborne disease in human, this study designed to determine the microbial contamination of traditional ice cream products sold in Tehran from March 2008 to March 2011.In this cross-sectional, descriptive-analytical study, the ice cream samples were collected randomly from different vendors in Tehran and transported to the laboratory of Food and Drug Deputy of Shahid Beheshti University of Medical Sciences. The samples were examined for their total mesophilic aerobic bacteria, Enterobacteriacea, Escherichia Coli, Staphylococcus aureus and mold. The laboratory examinations were conducted using the specific national standards for any organism. The descriptive data were obtained and the chi-square test, at significance level of p<0.05, was used to compare the level of contamination between different time periods. Ninety four percent of the samples did not meet the national microbiological standards for ice creams. Total mesophilic aerobic bacteria, rate of Enterobacteriaceae and mold were higher than the safety limits according to Iranian national standards in 88.1%, 100% and 73% of the samples, respectively. Escherichia Coli and Staphylococcus aureus were isolated from 23.6% and 4% of the samples, respectively. There was a significant difference between Staphylococcus aureus contamination of the ice creams in the Spring-Summer periods of 2008 to 2011. No other significant difference was shown between different time periods in this study. This study did not show any improvement in the microbial contamination of the ice creams during the study period.The high microbial load of the traditional ice creams confirms unhygienic conditions on their process of production and sale. Implementation of hygienic practices and regular control on these processes is recommended to minimize the risk of contamination.