assesment of sodium benzoate concentration in doogh distributed in isfahan, iran

background : doogh is a fermented beverage in which microbial spoilage is possible. benzoic acid and its salt (sodium benzoate) are added to doogh as antimicrobial preservative to control microbial spoilage. however, the use of this preservative has been prohibited in milk and dairy products such as food and drug administrationand institute of standards and industrial research of iran. thus, the aim of the present study was to determine sodium benzoate concentration in doogh distributed in isfahan, iran. methods: in this descriptive, cross-sectional study, the sodium benzoate concentration of 36 samples of 3 brands of doogh (a, b, and c) distributed in isfahan in 2015 were assessed using high performance liquid chromatography (hplc). collected data were analyzed using anova in spss software. all p values of smaller than or equal to 0.05 were considered significant. findings: results showed that the highest and lowest concentrations of sodium benzoate were found in brand c and a doogh with amounts of 4.84 ± 0.55 and 4.03 ± 0.11 ppm, respectively. sodium benzoate was detected in all doogh samples. a significant difference was observed in sodium benzoate concentration between the 3 different dairy brands (p < 0.001). conclusion: the existence of low concentrations of sodium benzoate in all doogh samples may be due to the natural occurrence of this compound in yoghurt and its transfer to doogh. furthermore, due to the great difference of the detected sodium benzoate in the current study with the permitted amount in codex international standard for fermented drinks (300 mg/kg), it the suggested to define the permitted level of sodium benzoate in doogh based onnational nutritional pattern.