Staphylococcus aureus is a gram-positive bacterium, commonly found in the nostrils, on the skin and on the hair of warm-blooded animals, including humans. It can produce a wide variety of virulence...

Staphylococcus aureus enterotoxin in food of animal origin and staphylococcal food poisoning risk assessment from farm to table

Novel species-specific targets for real-time PCR detection of four common pathogenic Staphylococcus spp.

Plant extracts are obtained by extracting bioactive compounds from various plant sources such as leaves, seeds, fruits, roots, stems, and agro-industry byproducts. These are rich sources of bioactive molecules such as polyphenols (flavonols, anthocyanins, flavanols, benzoic acid, tannin, lignin, stilbenes, cinnamic acid, phenolic acids), terpenoids (carotenoids, terpenes, triterpenes, phytosterols, iridoids), organo-sulfurs, and alkaloids. These molecules exert antioxidant and antimicrobial effects; hence widely utilized as potential natural preservatives by partial or fully replacing the synthetic preservatives. Plants extracts could be used in cured and smoked meat products as nitrites/nitrates replacer by reducing residual nitrite, N-nitrosamine formation, and antimicrobial effect. The application of plant extracts by replacing synthetic additives helps in improving the functionality of meat products, the development of wellness foods or clean-label foods, and the production of healthier meat products without or with minimum use of synthetic additives. There should be a proper focus on using green, nontoxic solvents, exploring the novel, sustainable and economical source of bioactive compounds, efficient agro-industrial waste utilization, and novel environmentally friendly, sustainable green processing technologies to extract bioactive compounds from the plant source. The present review is intended to provide recent insights on technological aspects of extracting functional compounds from plant biomass and the utilization of these plant extracts as a potential alternative to synthetic preservatives in the meat matrix. Novelty impact statement Plant extracts are rich sources of bioactive compounds exerting antioxidant, antimicrobial, and health-promoting activities. The application of plant extracts in the meat products would help in reducing the use of synthetic additives, replacer of nitrites/nitrates, production of wellness/healthier foods, and clean label foods. The applications of plant extracts are also successfully explored for developing active films for extending shelf life and quality preservation, preparation of intelligent pH strips for in situ quality monitoring, and use of various combinations of extracts with essential oils or even with a lower dose of antibiotics to reduce the risk of antibiotic resistance. 

Overview of Plant Extracts as Natural Preservatives in Meat

Large-Scale Staphylococcus aureus Foodborne Disease Poisoning Outbreak among Primary School Children

Possible contamination by Staphylococcus aureus of the production environment and of the meat of a canned meat production factory was analysed. A total of 108 samples were taken from nine critical control points, 13 of them were positive for S. aureus. None of the isolates produced enterotoxins. To determine how much time can elapse between can seaming and sterilisation in the autoclave without any risk of enterotoxin production by S. aureus, the growth and enterotoxin production of three enterotoxin A producing strains of S. aureus (one ATCC strain and two field strains) in canned meat before sterilisation was investigated at three different temperatures (37, 20 and 10 °C). Two types of meat were used, one with and one without sodium nitrite. In the canned products, the spiked bacteria spread throughout the meat and reached high levels. Enterotoxin production was shown to start 10 hours after incubation at 37 °C and after 48 h after incubation at 20 °C; the production of enterotoxin was always detected in the transition between the exponential and the stationary growth phase. At 10 °C, the enterotoxin was never detected. The statistical analysis of the data showed that the difference between the two different types of meat was not statistically significant (p value > 0.05). Since it is well known that following heat treatment, staphylococcal enterotoxins, although still active (in in vivo assays), can be undetectable (loss of serological recognition) depending on the food matrix and pH, it is quite difficult to foresee the impact of heat treatment on enterotoxin activity. Therefore, although the bacteria are eliminated, the toxins may remain and cause food poisoning. The significance of the results of this study towards implementing good manufacturing practices and hazard analysis critical control points in a canned meat factory are discussed with reference to the management of pre-retorting steps after seaming.

Vito Gullo

Papers

Study on the Growth and Enterotoxin Production by Staphylococcus aureus in Canned Meat before Retorting.