The determination of geographical origin is a demand of the traceability system of import-export food products. One hypothesis for tracing the source of a product is by global analysis of the microbial communities of the food and statistical linkage of this analysis to the geographical origin of the food. For this purpose, a molecular technique employing 26S rDNA profiles generated by PCR-DGGE was used to detect the variation in yeast community structures of three species of Physalis fruit (Physalis ixocarpa Brat, Physalis pubescens L, Physalis pruinosa L) from four Egyptian regions (Qalyoubia, Minufiya, Beheira and Alexandria Governments). When the 26S rDNA profiles were analysed by multivariate analysis, distinct microbial communities were detected. The band profiles of Physalis yeasts from different Governments were specific for each location and could be used as a bar code to discriminate the origin of the fruits. This method is a new traceability tool which provides fruit products with a unique biological bar code and makes it possible to trace back the fruits to their original location.

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The study investigated the occurrence of natural fungal contaminants in food commodities consumed in Durban, South Africa. A total of 110 samples including Bambara groundnut, maize and maize‐derived products, rice, and spices were collected from open markets and retail stores and screened for fungal contaminants using conventional and molecular methods. A total of 179 isolates belonging to fungal genera including Aspergillus, Penicillium, and Fusarium were recovered. Aspergillus (52.5%) and Penicillium (31.8%) were the most prevalent genera, contaminating 85.5% and 51.8% of the total samples analyzed, respectively. Bambara groundnut (100%), spices (89.5%), rice (86.9%), and maize and maize‐derived products (71.9%) were contaminated by Aspergillus sp. Bambara groundnut (64.7%) and spices (44.7%) were contaminated by Aspergillus flavus. Penicillium citrinum was recovered from spices (71.1%), Bambara groundnut (61.7%), rice (34.8%), and maize and maize‐derived products (31.3%). Some of the isolated fungi are mycotoxin producers and their detection raise concerns on consumers' health. Practical applications Fungal contamination of agricultural products poses a challenge to global food security. Mycotoxins, the toxigenic metabolites produced by some fungal species, are not completely destroyed by processing operations, and are carried over into processed food, through which they may cause harm to consumers. Routine tests on the mycological quality of consumer goods have therefore become pertinent. This study reports the isolation of live pathogenic fungi in commonly consumed food commodities, necessitating the need for regular routine checks to ensure the mycological safety of agricultural products offered for sale to consumers. As proliferation of these fungi is influenced by storage conditions, this study will also contribute to devising appropriate storage management techniques for these commodities.

IM designed the study, performed the statistical analysis, wrote the protocol, and wrote the first draft of the manuscript. Authors DM and CMFM managed the analyses of the study.'Author DM managed the literature searches. All authors read and approved the final manuscript.

Increasing research has highlighted the effects of changing climates on the occurrence and prevalence of toxigenic Aspergillus species producing aflatoxins. There is concern of the toxicological effects to human health and animal productivity following acute and chronic exposure that may affect the future ability to provide safe and sufficient food globally. Considerable research has focused on the detection of these toxins, based on the physicochemical and biochemical properties of the aflatoxin compounds, in agricultural products for human and animal consumption. As improvements in food security continue more regulations for acceptable levels of aflatoxins have arisen globally; the most stringent in Europe. These regulations are important for developing countries as aflatoxin occurrence is high significantly effecting international trade and the economy. In developed countries analytical approaches have become highly sophisticated, capable of attaining results with high precision and accuracy, suitable for regulatory laboratories. Regrettably, many countries that are affected by aflatoxin contamination do not have resources for high tech HPLC and MS instrumentation and require more affordable, yet robust equally accurate alternatives that may be used by producers, processors and traders in emerging economies. It is especially important that those companies wishing to exploit the opportunities offered by lucrative but highly regulated markets in the developed world, have access to analytical methods that will ensure that their exports meet their customers quality and safety requirements. This work evaluates the ToxiMet system as an alternative approach to UPLC–MS/MS for the detection and determination of aflatoxins relative to current European regulatory standards. Four commodities: rice grain, maize cracked and flour, peanut paste and dried distillers grains were analysed for natural aflatoxin contamination. For B1 and total aflatoxins determination the qualitative correlation, above or below the regulatory limit, was good for all commodities with the exception of the dried distillers grain samples for B1 for which no calibration existed. For B1 the quantitative R2 correlations were 0.92, 0.92, 0.88 (<250 μg/kg) and 0.7 for rice, maize, peanuts and dried distillers grain samples respectively whereas for total aflatoxins the quantitative correlation was 0.92, 0.94, 0.88 and 0.91. The ToxiMet system could be used as an alternative for aflatoxin analysis for current legislation but some consideration should be given to aflatoxin M1 regulatory levels for these commodities considering the high levels detected in this study especially for maize and peanuts. (Résumé d'auteur