Safety Evaluation of Doogh, a Traditional Iranian Dairy Product, in Khuzestan, Iran: A Cross-Sectional Study on Microbiological, Chemical and Toxicological Aspects

A lot of people consume traditional foods throughout the world, however there are concerns for their safety. The purpose of the current study is to evaluate the safety of traditional doogh (a traditional fermented dairy beverage) with respect to microbiological, chemical, and toxicological aspects.

89 samples of traditional doogh from Khuzestan province, Iran, were analysed according to microbiological (Staphylococcus aureus, Echerichia coli, coliforms, mold and yeast), chemical (pH, total solid, fat, and salt content), and toxicological (aflatoxin M1, potassium sorbate, sodium benzoate, and natamycin) aspects.

Results showed that 89.88% of samples would be rejected according to the guidelines specified by the Institute of Standards and Industrial Research of Iran (ISIRI). 78 sample had higher mold and yeast than standard. The salt content of five out of 89 samples were higher than the established Iranian standard.

The most challenging problem was mold and yeast contamination, indicating poor hygienic manufacturing conditions. However, the unfavorable conditions for microbial growth such as low pH may prevent the toxic metabolites formation, and therefore, consuming it presents no major concerns to public health. Nonetheless, the authors suggest that efforts should be made to improve hygienic conditions in traditional doogh manufacturing environments.