FERMENTATION OF FLOURS FROM THE AMAZON BIOME: IMPACT ON THEIR COMPOSITION AND TECHNO-FUNCTIONAL PROPERTIES

The Amazon Biome has a great potential for obtaining innovative food products and ingredients. Fermentation by probiotic microorganisms is an interesting strategy to modify characteristics of several plant matrices and aggregate value to the biotransformed products. In this work, Brazil nut (Bertholletia excelsa) and babassu mesocarp (Attalea speciosa) flours were fermented by the probiotic yeast Saccharomyces cerevisiae var. boulardii in 250 mL Erlenmeyer flasks containing 50 mL of each flour suspension (100 mg mL–1), inoculated with the yeast (109 cells mL–1) and incubated at 30°C under 150 rpm agitation by 12 h. The fermented products were compared to their respective non-fermented flours in terms of nutritional composition, amino acid profile and the following techno-functional properties: water and oil absorption, emulsifying capacity, solubility and gel formation. Babassu flour showed a high amount of carbohydrate (96.41g/100g), followed by protein (1.77g/100g), ash (1.18g/100g) and lipid (0.64g/100g). Brazil nut flour, in turn, showed higher lipid (44.62g/100g) and protein (33.65g/100g) contents. After fermentation, the babassu flour showed a 23% increase in its protein content, positively changing the amino acid profile (quantitatively and qualitatively). Brazil nut flour showed all the essential amino acids and there was a slightly increased of their content after fermentation. The content of glutamic acid, glycine and hydroxyproline were the ones that showed the greatest increases after fermentation for both samples. For babassu flour, fermentation significantly increased (p < 0.05) the oil absorption capacity in 40% and improved gel formation. The fermented flour of Brazil nut showed an increase of 16% and 208% in the absorption capacity of water and oil, respectively. The emulsifying capacity was not affected by fermentation, and Brazil nut had higher values (80.11%) than babassu samples (28.75%). Solubility (pH range from 1 to 10) of both flours was also improved by fermentation.