Elaboração de fermentados alcoólicos de araçá-boi: do planejamento fatorial à caracterização química e avaliação antioxidante

Abstract

The araçá-boi (Eugenia stipitata McVaugh) is an unconventional fruit from the Amazon, whose chemical composition rich in antioxidant compounds has already been described in the literature. This fruit is little explored by the Amazonian population, or even by the food industry. Fermented beverages are one of the alternatives for the utilization and valuation of these fruits. Such drinks can be analyzed qualitatively and quantitatively by analytical techniques such as Nuclear Magnetic Resonance - NMR and Mass Spectrometry - MS. Therefore, this work aimed to conduct a study of optimization of the production process of fermented beverages of araçá-ox using a factorial design, as well as contribute to the chemical characterization and evaluation of antioxidant capacities of the products obtained. Three production processes were carried out. Stage I consisted of selecting two of the yeast variations with the best antioxidant response (Biolievito Bayanus and Arom Cuvee). Stage II consisted of the evaluation of the filtration process, verifying if the filtration interferes with the antioxidant responses. This screening resulted in a complete factorial design of 23 [factors: Yeast Type (Biolievito Bayanus and Arom Cuvee); Process (filtering and non-filtering) and Temperature (18 °C and 28 °C)]. Factorial design effect calculations reveal that the factor that most contributes to the antioxidant response was temperature, while yeast type was the least relevant factor. NMR and MS analyzes resulted in the identification of ten organic substances (malic, citric, gallic, succinic and formic acids, as well as tyrosol, sucrose, α-glucose, β-glucose and ethanol). Quantitative NMR analysis showed that the highest concentrations of phenolic compounds were present in the beverages obtained at 28 °C (C28F: 920.0 μmol L -1 , C28NF: 861.75 μmol L-1

, B28NF: 842.2 μmol L -1 and B28F: 835.3 μmol L-1). The alcohol content remained between 11.5 oG.L. and 13.6 oG.L.. The B18NF sample obtained the best response for the DPPH / IC50 (692.4 ± 8.2 μg mL-1 )

and ABTS (1,261.0 ± 0.0 μg mL-1

) assay. 1). The chemometric analyzes revealed that the samples have a very similar chemical profile, but differ by the concentrations of the compounds present in these fermented. Given this, this work contributed to the development of an optimized production process of fermented beverages of araçá-boi, as well as the description of the chemical composition of these Amazonian products.