The concept of functional food has evolved throughout the years. These days we define a food to be functional when it confers a benefit to human health. Lactic acid fermentation is one of the most important and used food processing technologies to produce this type of food. Fermentation of Lactobacillus Paracasei CBA L74 - a homofermentative, gram positive probiotic - on rice flour suspension has been proved to be a successful route to produce functional foods. However, the process was characterized by high energy consumption, low air sparging and complex expensive metabolite separation.
A research program has been developed to carry out L. Paracasei fermentation using a low viscosity medium based on rice flour suspension. Fractionation of rice flour suspension provided a medium characterized by low amounts of solids and nutrients at concentration high that support the microorganism growth. Fermentations were carried in a 1L batch reactor equipped with an agitation systems designed to provide uniform mixing. The composition of the medium; cells, glucose, protein, pH, metabolite production as well as L. Paracasei’ growth trend was analysed throughout the process. Fermentation on supernatant obtained from rice flour and water suspension through centrifugation were possible to produce a potential probiotic functional food with a good bacterial charge.