The efficacy of solvents, ascorbic acids, and pH on the yield of betacyanin and betaxanthin extraction compounds of Pablo beetroot
摘要
Betalains are valuable natural pigments with growing demand in food, nutraceutical, and dye applications, yet their extraction efficiency varies widely according to solvent polarity, pH, and antioxidant environment. This study systematically investigates the impact of solvent compositions, pH, and ascorbic acids concentration on the extraction efficiency of betalains pigment from Pablo beetroot (Beta vulgaris Cv. Pablo). Using a blending extraction method, 5 g of beetroot was treated with varying ethanol and methanol concentrations (25–100% v/v), ascorbic acid levels (5–50 mM), and McIlvaine/phosphate buffers (pH 3.0–8.0). The extracts were analysed spectrophotometrically for betacyanin (538–600 nm) and betaxanthin (476–600 nm) concentrations. The results at 10 mM provided the optimum extraction of 1631 mg/100 g DW betacyanin; 1582 mg/100 g DW betaxanthin, followed by 50% methanol of 1439 mg/100 g DW betacyanin; 1253 mg/100 g DW betaxanthin, and later with buffers at pH 3–6 of 1400 mg/100 g DW betacyanin; 1180 mg/100 g DW betaxanthin. These findings demonstrate that 50% methanol (moderate solvent polarity) pH 3–4 (mildly acidic pH), and 10 mM (low-to-moderate ascorbic acid) concentrations maximise pigment yield and stability, providing practical guidelines for food, nutraceutical, and natural dye applications.