Ready‐to‐eat foods (RTEs) are foods consumed without any further processing. They are widely consumed as choice meals especially by school‐aged children and the fast‐paced working class in most low‐ and middle‐income countries (LMICs), where they contribute substantially to the dietary intake. Depending on the type of processing and packaging material, RTEs could be industrially or traditionally processed. Typically, RTE vendors are of low literacy level, as such, they lack knowledge about good hygiene and food handling practices. In addition, RTEs are often vended in outdoor environments such that they are exposed to several contaminants of microbial origin. Depending on the quantity and type of food contaminant, consumption of contaminated RTEs may result in foodborne diseases and several other adverse health effects in humans. This could constitute major hurdles to growth and development in LMICs. Therefore, this review focuses on providing comprehensive and recent occurrence and impact data on the frequently encountered contaminants of microbial origin published in LMICs within the last decade (2009 to 2018). We have also suggested viable food safety solutions for preventing and controlling the food contamination and promoting consumer health.

Mycological investigation of various foods (mainly cowpea, groundnut, maize, rice, sorghum) and agricultural soils from two states in north-central Nigeria (Nasarawa and Niger), was conducted in order to understand the role of filamentous fungi in food contamination and public health. A total of 839 fungal isolates were recovered from 84% of the 250 food and all 30 soil samples. Preliminary identifications were made, based on macro- and micromorphological characters. Representative strains (n = 121) were studied in detail using morphology and DNA sequencing, involving genera/species-specific markers, while extrolite profiles using LC-MS/MS were obtained for a selection of strains. The representative strains grouped in seven genera (Aspergillus,Fusarium,Macrophomina,Meyerozyma,Neocosmospora,NeotestudinaandPhoma). Amongst the 21 species that were isolated during this study was one novel species belonging to theFusarium fujikuroispecies complex,F. madaensesp. nov., obtained from groundnut and sorghum in Nasarawa state. The examined strains produced diverse extrolites, including several uncommon compounds: averantinmethylether inA. aflatoxiformans; aspergillimide inA. flavus; heptelidic acid inA. austwickii; desoxypaxillin, kotanin A and paspalitrems (A and B) inA. aflatoxiformans,A. austwickiiandA. cerealis; aurasperon C, dimethylsulochrin, fellutanine A, methylorsellinic acid, nigragillin and pyrophen inA. brunneoviolaceus; cyclosporins (A, B, C and H) inA. niger; methylorsellinic acid, pyrophen and secalonic acid inA. piperis; aspulvinone E, fonsecin, kojic acid, kotanin A, malformin C, pyranonigrin and pyrophen inA. vadensis; and all compounds inF. madaensesp. nov.,Meyerozyma,NeocosmosporaandNeotestudina. This study provides snapshot data for prediction of food contamination and fungal biodiversity exploitation.

Contamination of ready‐to‐eat (RTE) foods by pathogenic bacteria may predispose consumers to foodborne diseases. This study investigated the presence of bacterial contaminants and their antibiotic susceptibility patterns in three locally processed RTE foods (eko, fufu and zobo) vended in urban markets in Ogun state, Nigeria. Bacteria isolated from a total of 120 RTE food samples were identified by 16S rRNA gene phylogeny while susceptibility patterns to eight classes of antibiotics were determined by the disc diffusion method. Species belonging to the genera Acinetobacter and Enterobacter were recovered from all RTE food types investigated, Klebsiella and Staphylococcus were recovered from eko and fufu samples, while those of Shigella were recovered from eko samples. Enterobacter hormachei was the most prevalent species in all three RTE food types. Precisely 99% of 149 isolates were multidrug‐resistant, suggesting a high risk for RTE food handlers and consumers. Co‐resistance to ampicillin and cephalothin was the most frequently observed resistance phenotype. Results demonstrate that improved hygiene practices by food processors and vendors are urgently required during RTE processing and retail. Also, adequate food safety guidelines, regulation and enforcement by relevant government agencies are needed to improve the safety of RTE foods and ensure the protection of consumer health.

A comprehensive study of bacterial and biotoxin contaminants of ready-to-eat (RTE) foods in Nigeria is yet to be reported. Hence, this study applied 16S rRNA gene sequencing and a dilute-and-shoot LC-MS/MS method to profile bacteria and biotoxins, respectively, in 199 RTE food samples comprising eko (n = 30), bread (n = 30), shawarma (n = 35), aadun (n = 35), biscuits (n = 34), and kokoro (n = 35). A total of 631 bacterial isolates, clustered into seven operational taxonomic units, namely Acinetobacter, Bacillus, Klebsiella, Proteus and Kosakonia, Kurthia, and Yokenella, that are reported for the first time were recovered from the foods. One hundred and eleven metabolites comprising mycotoxins and other fungal metabolites, phytoestrogenic phenols, phytotoxins, and bacterial metabolites were detected in the foods. Aflatoxins, fumonisins, and ochratoxins contaminated only the artisanal foods (aadun, eko, and kokoro), while deoxynivalenol and zearalenone were found in industrially-processed foods (biscuit, bread, and shawarma), and citrinin was present in all foods except eko. Mean aflatoxin (39.0 µg/kg) in artisanal foods exceeded the 10 µg/kg regulatory limit adopted in Nigeria by threefold. Routine surveillance, especially at the informal markets; food hygiene and safety education to food processors and handlers; and sourcing of high-quality raw materials are proposed to enhance RTE food quality and safeguard consumer health.

Geophagia (i.e. calabash chalk consumption) is notably prevalent among pregnant women in parts of Africa and Asia. It is often used to alleviate pregnancy-related symptoms, such as nausea, a practice that carries complex cultural, nutritional, and health implications. This review examines the microbiological and chemical safety profiles of calabash chalk, emphasizing its potential impacts on maternal health. The cultural context of geophagia and perceived health benefits of calabash chalk consumption are explored, in addition to its mineral content, pesticide, heavy metal residues, and geographical variability in toxicity. Likewise, the balance between beneficial probiotics and pathogenic microorganisms, along with the potential risks these pose, to maternal health is assessed. This review also delves into the health risks associated with pesticide and heavy metal exposure, such as developmental toxicity and neurological impacts. Furthermore, potential nutritional benefits, including minerals such as calcium and iron, and its possible probiotic effects are discussed. Additionally, the review examines existing safety regulations, identifies gaps in monitoring and standards, and proposes directions for future research, particularly regarding the long-term effects of calabash chalk consumption during pregnancy. Overall, there is need for a balanced understanding of the risks and benefits of geophagia to promote maternal and foetal well-being.