DETERMINATION OF ANTIOXIDANT ACTIVITY IN ALCOHOLIC AND ACETIC BEVERAGES PRODUCED FROM ORANGE PASSION FRUIT (Passiflora caerulea L.)

The orange passion fruit (Passiflora caerulea L.) is a native fruit widely found in the southern region of Brazil. The pulp presents high content of sugars and bioactive compounds, making it an excellent feedstock for elaborating fermented food products, such as alcoholic and acetic beverages. This study evaluated the in vitro antioxidant activity of fermented beverages (alcoholic and acetic) produced with orange passion fruit pulp. For this, potassium metabisulfite (50 mg/L) and Saccharomyces bayanus (1 g/L) were added to the orange passion fruit pulp (15 °Brix). The alcoholic fermentation was conducted at 25 °C for seven days. The acetic beverage was obtained by adding unpasteurized vinegar (mother of vinegar) to the alcoholic. The acetification occurred at 25 °C under aerobic conditions for 19 days. The antioxidant activity was determined through the inhibition of ABTS+ free radical and the reduction potential of iron ion (FRAP) method. The results revealed that the beverages presented a high antioxidant activity. The alcoholic beverage demonstrated the highest antioxidant activity (p ≤ 0.05), reaching 14.52 ± 0.17 µM Trolox equivalent (TEAC)/mL, while the acetic beverage presented 11.23 ± 0,10 µM TEAC/mL. The same behavior was observed in the FRAP method, where the alcoholic beverage (6.56 ± 0.05 µM TEAC/mL) presented a high antioxidant activity when compared with the acetic beverage (5.21 ± 0.02 µM TEAC/mL). The results obtained demonstrate that alcoholic and acetic fermentation are promising alternatives for the diversification of fermented beverages. The antioxidant activities can be attributed to different bioactive compounds presented in the orange passion fruit pulp, such as polyphenols. Therefore, the production of fermented beverages with Brazilian native fruits can be an alternative to provide innovative functional foods and beverages, with potential health benefits, contributing to the revolution of food science and nutrition.