Boosting health-promoting bacteria in foods
When people hear the word bacteria, most think of infection and antibiotics. The truth is that the human intestinal tract is absolutely loaded with bacteria that help keep people healthy. Endogenous gut-dwelling bacteria fight harmful bacteria, aid in digestion and nutrient absorption, and contribute to immune function. However, a variety of factors cause an imbalance between beneficial and harmful bacteria. These include illness, poor diet, stress and over-use of antibiotics. Given the growing focus on disease prevention, addition of health-promoting bacteria to produce so-called probiotic (literally ‘for life’) foods is on the rise. Probiotics are one of many functional foods, with additives for specific functions other than nutrition. Studies are mixed but evidence suggests that certain probiotic therapies can reduce symptoms of irritable bowel syndrome, Crohn’s disease and infectious or antibiotic-associated diarrhoea. However, probiotics added to foods can have an undesirable effect on food texture. In addition, they can be partially destroyed during manufacturing, storage and even by the acidic stomach environment. European researchers sought to develop an innovative microencapsulation process to preserve probiotics while making the microcapsules small enough to be added to a wide variety of foods with no noticeable effect on texture. Funding provided by the EU for the ‘Novel flow focusing technology to produce microencapsulated probiotic bacteria for the food sector’ (Flocap) project enabled partner scientists to exploit this potentially huge market. Investigators addressed the polymer coating itself and an innovative flow focusing technology with a new nozzle designed specifically for the purpose at hand. The processing required conditions gentle enough to ensure high bacterial survival rates, small and uniform capsule size, and feasible scale-up production processes. With increasing public demand for healthy and health-promoting foods, the technology could revolutionise the probiotic food sector.