The microbiological quality of street foods in Jakarta as compared to home-prepared foods and foods from tourist hotels

Abstract

Street foods are ready-to-eat foods which are important for the diet of especially poor people in developing countries. However, street foods are often suspected of being contaminated with pathogenic bacteria. The quality of street foods was compared with similar home-prepared foods and foods obtained from tourist hotels. Samples of three types of Indonesian dishes were analyzed for indicator organisms using dry hydratable film. Additional western meals were also obtained from the hotels. Background information was obtained from the food preparers by using a questionnaire. The microbial quality of nasi goreng (fried rice) and sate ayam (grilled chicken with peanut sauce) was usually acceptable: numbers of total coliform were low and often no Escherichia coli was found. Gado gado (a dish mainly consisting of vegetables, peanut sauce and bean curd) had higher contamination levels. The gado gado obtained from street food vendors had especially high counts of total coliform and Escherichia coli with median counts of 5.5 × 106 (total coliform) and 6.0 × 103 (E. coli), respectively. The serving temperature might contribute to this difference in contamination level because nasi goreng and sate ayam are served hot and gado gado is served cold. The quality of the three western foods obtained from hotels was not better than that of the Indonesian dishes served; however the quality differed among the four hotels from which samples were obtained. Even food obtained from five-star hotels was sometimes unsafe (counts per gram for APC > 107; total coliform > 102; E. coli > 107). Lack of facilities and a limited knowledge of hygiene, particularly of the street food vendors, may have led to poor handling practices, such as storing cooked vegetables at ambient temperature for long periods, resulting in relatively high levels of contamination.