Comparison of physicochemical properties and economic gain from three‐stage and two‐stage sequential valorization of mango peels

• Published in: Biofuels, bioproducts and biorefining bioproducts and biorefining, 2021-03, Vol.15 (2), p.454-467
• Main Authors: Mugwagwa, Lindleen R., Chimphango, Annie F.A.
• Format: Article
• Language: English
• Subjects: Acetic acid; Ammonium; Ammonium compounds; anthocyanin; Anthocyanins; Antioxidants; Economic benefits; Economics; Ethanol; labile co‐products; mango peels; Mangoes; Net present value; Oxalic acid; Payback periods; Pectin; Physicochemical processes; Physicochemical properties; Polyphenols; Properties (attributes); Residues; sequential extraction
• ISSN: 1932-104X; 1932-1031
• DOI: 10.1002/bbb.2166

Three‐stage sequential extraction of anthocyanins, polyphenols, and pectin has the potential to enhance the product's functional properties and the economic value of mango (Mangifera indica L.) peels beyond the two‐stage processes (anthocyanin‐pectin and polyphenol‐pectin). A three‐stage process was developed by incorporating a polyphenol extraction stage in a sequential process where anthocyanins and pectin were co‐extracts. Anthocyanins were extracted first (80% ethanol (EC)/2% acetic acid/25 °C/1 h), generating a residue from which polyphenols were extracted (65–85% EC/20–80 min/70 °C), based on a full factorial statistical experiment. Pectin was subsequently extracted from the second‐stage residues (0.25% ammonium oxalate / oxalic acid / 85 °C / 1 h). The economic benefits (net present value (NPV), payback period (PBP), product minimum selling price (PMSP) of the three‐stage sequential process (anthocyanin, polyphenol, and pectin) and the two‐stage processes (anthocyanin‐pectin and polyphenol‐pectin) were evaluated over a plant life of 25 years. Polyphenols and pectin from the three‐stage process had >65% higher antioxidant capacity and up to 10.4% higher purity, respectively, when compared with those from the two‐stage processes. There is also more economic gain from the three‐stage process (NPV −$4 31 285, PBP −3 years, PMSP < $10/kg) than the anthocyanin‐pectin process (NPV −$3 76 917, PBP −3.22 years, PMSP < $10/kg) and the polyphenol‐pectin process (NPV −$235 599, PBP −4.29 years, PMSP < $30/kg). Thus, three‐stage sequential extraction is an economic process, which enables the recovery of three value‐added food ingredients with improved functional properties from mango peels.© 2020 Society of Chemical Industry and John Wiley & Sons, Ltd