Steviol glycosides and bioactive compounds of a beverage with exotic fruits and Stevia rebaudiana Bert. as affected by thermal treatment

Abstract

The aim of this study was to investigate the effects of thermal processing on physicochemical properties, steviol glycosides, bioactive compounds, and antioxidant capacity degradation of a beverage based on exotic fruit juices, orange juice, açaí, and oat and sweetened with Stevia rebaudiana water extracts at different concentrations. The experimental design comprised a response surface methodology according to a central composite face-centered design. The variable ranges were 60–99°C, 0.25–15 min, 0–2.5% Stevia percentage. This design was used to determine the optimal thermal processing-Stevia concentration in order to obtain the best retention of bioactive compounds and physicochemical properties in the beverage following thermal processing. Thermal processing conducted in the sample containing 2.5% Stevia at 82.4°C for 3.8 min led to the beverage with the greatest presence of antioxidant compounds. The evaluation of the thermal processing critical parameters on antioxidant compounds can contribute to achieve optimal processing conditions in order to obtain new beverages with high antioxidant potential.

Keywords

• stevia rebaudiana bertoni
• exotic fruits
• thermal processing
• physicochemical properties
• steviol glycosides
• bioactive compounds
• total antioxidant capacity