Biofortification of fermented foods with selected yeasts and process for raised folate content and mineral availability

Research Project, 2012 – 2015

The focus of the project is on biosynthesis of folic acid and enzymatic degradation of phytate by selected yeasts. Phytate is abundant in all cereals and inhibits uptake of iron and zinc. Folate, iron and zinc deficiencies are all highly prevalent in the world, affecting human health in many negative ways. The objective of the proposed project is to use selected yeasts and bio-processing to increase the levels of natural folate and mineral availability in fermented foods such as bread. We will use knowledge from previous projects to select high-folate baker´s yeast and other high phytase yeasts. We will also from earlier knowledge develop a pre-fermentation step in which we induce a high folate and high-phytase state, respectively. The yeasts Pichia kudriavzevii TY13 and Hanseniaspora guilliermondii TY14 were isolated from Tanzanian cereal-based fermented food togwa. These yeasts show unusual high phytase activity (phytate degradation) and secretion which efficiently releases minerals from otherwise unavailable phytate complex. We see an advantage in natural biofortification, in contrast to add synthetic folic acid, iron and zinc. Furthermore our strategy is to achieve the biofortification completely without GMO. The strains have not been modified but were selected as naturally high in folate and phytase. The research is expected to be useful in industrial as well as home-made fermented foods with higher nutritional value.