Use of non-conventional yeasts isolated from Amazonia stingless bees pollen in fermentative processes

The demand for non-conventional yeasts, mainly in fermentative environments, has been increasing due to their use in a huge variety of foods. Drinks fermented by wild yeasts and with low alcohol content and/or with the production of differentiated aromas, called bioflavours, have gained prominence in the market and in scientific research. Pollen pots from native stingless bees can be appointed as an ideal location for prospecting these yeasts, since the diverse pollen mass collected by these bees undergoes a fermentation process by bacteria and yeasts. Therefore, this study aims to select, from stingless bee pollen, yeasts with maltose fermentation potential, either in simple fermentations or co-fermentations aimed at the production of craft beers. Different culture media were used for the isolation of yeasts. Qualitative tests of maltose fermentation, flocculation potential and resistance to high sugar concentration were performed to select the isolates. Once identified, the isolates were subjected to simple fermentation and co-fermentation at two temperatures, quantifying the concentration of viable and dead cells, the concentration of reducing sugars and the alcohol content. Two species, Hanseniaspora opuntiae and Wickerhamomyces anomalus showed better results in cell production in simple fermentation than commercial yeasts, but lower sugar consumption and alcohol production. These results indicate that yeasts isolated from stingless bee pollen can be used in the production of low-alcohol beverages or in co-fermentation to increase the production of bioflavours