Bacterial Contamination into Ready-to-Eat Foods Sold in Middle Thailand

Street food research worldwide: a scoping review

BACKGROUND

Street foods vary with respect to their nutritional value and safety characteristics and contribute to a sizable proportion of food intake in many populations worldwide. Therefore, the present study aimed to describe the coverage in the scientific literature of different health-related and socio-economic aspects of street food consumption and trading.

METHODS

Three electronic databases (searched from inception to 16 October 2017), a hand-search of relevant journals and backward citation tracking were used to identify eligible scientific articles with a main objective of investigating or reporting specific results on health-related or socio-economic aspects of street food. Papers published in English, Portuguese, French, Spanish or Italian, as well as English abstracts of papers published in other languages, were assessed. The selected articles were evaluated by two independent researchers and described according to year of publication, geographical distribution, definition of street food, main topics addressed and target population.

RESULTS

In total, 441 papers were selected. The number of publications has increased in recent years, almost half of them being published after 2012. Almost three-quarter of the articles were from Africa or Asia. Most studies addressed food safety (85.5%), whereas street food availability and consumption were much less frequently investigated (30.3%). The focus of the studies was usually the food (mostly its microbiological contamination) and the vendors (mostly their food handling), whereas consumers and vending sites were seldom evaluated. More than half of the studies did not specify a definition for street food.

CONCLUSIONS

Efforts are needed for a more widespread and comprehensive assessment of different issues related to street food availability and consumption in different settings, especially regarding street food offer, nutritional composition, and patterns of purchase and consumption by the population.

Multiplex PCR assay and lyophilization for detection of Salmonella spp., Staphylococcus aureus and Bacillus cereus in pork products

Multiplex PCR (m-PCR) has the potential for more rapid detection of pathogens compared to simple PCR through the simultaneous amplification of multiple gene targets using several sets of specific primers. Here, we developed an m-PCR assay which combined dry reagent mixtures for ready-to-use simultaneous detection of Salmonella spp., Bacillus cereus, and Staphylococcus aureus. The assay did not show cross-reactivity with several common bacterial pathogens and the detection limit was 10³ CFU/mL for mixed genomic DNA in pure culture. Lyophilized m-PCR reagents are stable for 2 months stored at 4 °C and for 1 month stored at 25 °C. Detection sensitivities of both dry and fresh mixes were able to simultaneously detect 10 CFU/mL of each pathogen in artificially inoculated samples after enrichment for 6 and 12 h. Results demonstrated that this method is both sensitive and specific and can be used for rapid detection and differentiation of foodborne diseases.