Ultrasonication-assisted extraction of anthocyanins from fruit and vegetable waste

Abstract

Anthocyanins, natural pigments with potent antioxidant and anti-inflammatory properties, are increasingly valued in food, pharmaceutical, and cosmetic industries for their health benefits and sustainable appeal. This review highlights ultrasound-assisted extraction (UAE) as a green and efficient method for recovering anthocyanins from fruit and vegetable waste. UAE leverages acoustic cavitation to enhance mass transfer and cell wall disruption, significantly improving extraction efficiency while reducing processing time and solvent use compared to conventional methods. Various studies reveal the key optimization parameters such as frequency (20–100 kHz), power (50–500 W), temperature (25–60°C), and solvent composition (e.g., acidified ethanol or natural deep eutectic solvents)—are critically to maximize yield and preserve anthocyanin stability. Comparatively studies reveal that UAE process achieves higher anthocyanin yields (20–60 %) than traditional techniques, with higher anthocyanin recovery in dry extract. The integration of UAE with NADES, such as choline chloride-citric acid, further enhances recovery rates while aligning with circular economy principles. However, industrial scaling faces challenges, including energy costs and the need for standardized equipment. The valorization of agro-industrial waste through UAE not only addresses environmental concerns but also generates high-value products for functional foods, nutraceuticals, and natural colorants. This review underscores UAE’s potential as a sustainable platform for anthocyanin extraction, bridging lab-scale innovation with industrial applications.