How do pH reduction and the addition of potassium metabisulfite impact color and the phenolic and anthocyanin profiles in red ara,ca (Psidium cattleianum Sabine) Wine?

This study evaluated the effect of reducing the pH of the must and adding potassium metabisulfite at different stages of the process on the physicochemical parameters, color, phenolic composition, and antioxidant activity of red araca wines. Six beverage formulations were prepared, three using the original pH of the pulp (pH 3.0) and the other three adjusting the pH to 2.8 with citric acid. Potassium metabisulfite (K2S2O5) was added to all the formulations but at different stages: 100 mg.L-1 in the pre-fermentation stage (MI), 50 mg. L-1 in the pre-fermentation stage + 50 mg.L-1 in the post-fermentation stage (MP), and 100 mg.L-1 in the post-fermentation stage (MF). The primary organic acids in red ara,ca wine were citric, malic, glycolic, and lactic acid. The initial pH influenced the red coloration of the CIELab color scale, with more significant effects observed in wines with an initial pH of 2.8. The MI and MP samples with an initial pH of 2.8 exhibited the highest antioxidant activity in the DPPH test, reaching 20.99 m M Trolox equivalent (TEAC).mL-1 and 20.28 m M.mL- 1 TEAC, respectively. Fourteen phenolic compounds were identified in the red ara,ca wine, with gallic acid, catechin, and tyrosol being the main compounds. Furthermore, the results revealed that reducing the pH to 2.8 and adding 100 mg of K2S2O5 in the pre-fermentation stage contributed significantly to a higher content of cyanidin-3-glucoside, aiding in preserving the beverage's reddish color. This study pioneered the production of fermented beverages from red araca. (c) 2024 SAAB. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.