Micro-organisms are important in food production and preservation. They are utilized in the manufacture of various food products such as cheeses, beers and yoghurt. Through the process of microbial bio-transformation, micro-organisms alter food components to form other foods with improved nutrient digestibility, organoleptic properties and probiotic factors. The fermentation process also enhances certain food properties like aroma, texture, flavour and digestibility. Further, fermented foods in addition to possessing a distinct flavour, are also safe and have a longer shelf life. In regard to nutrition function, the fermented foods produced have higher nutrient and mineral content. To preserve foods for longer, harmful micro-organisms are destroyed through processes such as heating, refrigeration, drying, irradiation etc.
Certain micro-organisms promote health by preserving gut microbiota and stimulating immunity. The bio-active compounds including enzymes, vitamins, bacteriocins and short-chain fatty acids are especially important. In particular, probiotics are associated with an improved gut microbiota composition and anti-inflammatory effects. There are specific strains of bacteria with probiotic factors though the benefits of each vary from one another. They wield their advantageous impacts through a number of processes that involve fighting against pathogenic bacteria, reducing gastro-intestinal pH, and altering immune responses.
Pathogenic micro-organisms are associated with high infection rates once they invade the food supply chain. Unsafe food handling practises increase the risks of food-borne illnesses in the production process. Pathogens such as E. coli and Salmonella cause food-borne illnesses.
In summary, micro-organisms contribute significantly in the food science and nutrition fields, in both positive and negative impacts from food manufacturing and preservation to food poisoning, food deterioration and infection; and, as health promoters through probiotics.