The current spreading of nanomaterial applications supports the search for further possible functions of theses diminutive particles. The antibacterial potentiality of zinc oxide (ZnO) nanoparticles (NPs), compared with conventional ZnO powder, against nine bacterial strains, mostly foodborne including pathogens, was evaluated using qualitative and quantitative assays. ZnO NP was more efficient as antibacterial agent than powder. Gram‐positive bacteria were generally more sensitive to ZnO than Gram negatives. The exposure of Salmonella typhimurium and Staphylococcus aureus to their relevant minimal inhibitory concentrations from ZnO NP reduced the cell number to zero within 8 and 4 h, respectively. Scanning electron micrographs of the treated bacteria with NPs exhibited that the disruptive effect of ZnO on S. aureus was vigorous as all treated cells were completely exploded or lysed after only 4 h from exposure. Promising results of ZnO NP antibacterial activity suggest its usage in food systems as preservative agent after further required investigations and risk assessments. PRACTICAL APPLICATIONS Foodborne pathogen invasion is still a recurrent serious problem facing researchers and food industry overseers. The introduction of novel powerful antimicrobial agents is of great importance for the control of pathogenic bacteria, especially antibiotic‐resistant strains. Zinc oxide (ZnO) nanoparticle (NP) could be one of these potential alternatives. This study focused on ZnO NP because of its increasing presence in many marketable products and that supports its application in food industries as a reasonably safe agent. The demonstrated antibacterial activity of ZnO NP recommends its possible application in the food preservation field; otherwise it can be applied as a potent sanitizing agent for disinfecting and sterilizing food industry equipment and containers against the attack and contamination with foodborne pathogenic bacteria.

No abstract

Mycotoxins contamination in some agricultural food commodities seriously impact human and animal health and reduce the commercial value of crops. Mycotoxins are toxic secondary metabolites produced by fungi that contaminate agricultural commodities pre- or postharvest. Africa is one of the continents where environmental, agricultural and storage conditions of food commodities are conducive of Aspergillus fungi infection and aflatoxin biosynthesis. This paper reviews the commodity-wise aetiology and contamination process of aflatoxins and evaluates the potential risk of exposure from common African foods. Possible ways of reducing risk for fungal infection and aflatoxin development that are relevant to the African context. The presented database would be useful as benchmark information for development and prioritization of future research. There is need for more investigations on food quality and safety by making available advanced advanced equipments and analytical methods as well as surveillance and awareness creation in the region.

The present opinion deals with the re-evaluation of the safety of food-grade carrageenan (E 407) and processes Eucheuma seaweed (E 407a) used as food additives. Because of the structural similarities, the Panel concluded that processed Eucheuma seaweed can be included in the evaluation of food-grade carrageenan. Poligeenan (average molecular weight 10-20 kDa) has not been authorised as a food additive and is not used in any food applications. In its evaluation of carrageenan (E 407) and processed Eucheuma seaweed (E 407a), the Panel noted that the ADME database was sufficient to conclude that carrageenan was not absorbed intact; in a subchronic toxicity study performed with carrageenan almost complying with the EU specification for E 407 in rats, the no-observed-adverse-effect level (NOAEL) was 3,400-3,900 mg/kg body weight (bw) per day, the highest dose tested; no adverse effects have been detected in chronic toxicity studies with carrageenan in rats up to 7,500 mg/kg bw per day, the highest dose tested; there was no concern with respect to the carcinogenicity of carrageenan; carrageenan and processed Eucheuma seaweed did not raise a concern with respect to genotoxicity; the NOAEL of sodium and calcium carrageenan for prenatal developmental dietary toxicity studies were the highest dose tested; the safety of processed Eucheuma seaweed was sufficiently covered by the toxicological evaluation of carrageenan; data were adequate for a refined exposure assessment for 41 out of 79 food categories. However, the Panel noted uncertainties as regards the chemistry, the exposure assessment and biological and toxicological data. Overall, taking into account the lack of adequate data to address these uncertainties, the Panel concluded that the existing group acceptable daily intake (ADI) for carrageenan (E 407) and processed Eucheuma seaweed (E 407a) of 75 mg/kg bw per day should be considered temporary, while the database should be improved within 5 years after publication of this opinion.

No abstract