Aplicação de leveduras autóctones de frutos da amazônia em panificação: fermentação e enriquecimento proteico com single-cell protein

Abstract

Wild yeasts isolated from fruits have biotechnological potential in fermentation processes, due to their ability to ferment complex sugars, tolerate both high temperatures and freezing, high concentrations of ethanol and media with high osmotic pressure. Unicellular Protein (SCP) are proteins derived from dry cells of microorganisms. Fermentation is one of the main microorganisms used for fermentation processes and production of SCP due to the Presumption of Qualified Safety certificate of several species. In this study, wild yeasts isolated from Amazonian fruits were evaluated for their application in bread fermentation and SCP production. Toxicity tests (biogenic amines and hydrogen sulfide), bread fermentation screening (stress test, carbohydrate fermentation, growth at different temperatures, osmotolerance, cryotolerance and ethanol tolerance) and SCP production (optical density, sugars ). total reducers, growth kinetics and protein analysis), resulting in the selection of two yeasts for the fermentation of breads (BCL 49.1 and BCL 5.2), and one (BCL 188.4) was chosen for the production of SCP, due to the higher production of proteins in the substrate used (40.22% without pineapple crown flour medium and 81.71% without YEPG broth). Breads made with BCL 49.1 and BCL 5.2 yeasts had less facilities than commercial S. cerevisiae, however, when it comes to the aroma profile of BCL 5.2, there was no significant difference compared to the control yeast. The addition of SCP to breads improved changes in physicochemical characteristics, such as an increase in lipid, ash, fiber and carbohydrate contents, and excess total reducing sugar contents. There was no statistical difference in protein content between enriched and non-enriched breads. It was concluded that the wild yeasts were able to ferment the breads and produce SCP with a high protein content, however, due to the amount of SCP used, they did not directly affect the amount of proteins in the breads, but the physicochemical characteristics.