Investigating the Water Relations in Aqueous Extract Powders of Mango (Mangifera indica) Peel and Seed Waste for Their Use in Food Matrices as a Value-Added By-Product

Abstract

This study investigated the potential uses of discarded mango peel and seed parts by analyzing their water sorption behavior, hydration kinetics, and stability when converted into extract powders at pH 3 and 10. The results revealed that peel extracts had a higher water adsorption capacity compared with seed extracts due to differences in their composition. Peel extracts were primarily composed of carbohydrates (approximately 75%) with a low protein content, while seed extracts contained fewer carbohydrates (less than 30%) but higher levels of proteins (more than 30%) and lipids. The critical water content for maintaining the glassy state of peel extract powders during storage was found to be 0.025 and 0.032 g of water/g for extracts obtained at pH 3 and 10, respectively. In contrast, the Tg values of seed extracts remained relatively unchanged across different water content levels, suggesting that proteins and lipids inhibited the water’s plasticizing effect in the solid matrix. These findings indicate that both mango waste fractions exhibit distinct hygroscopic behaviors, necessitating different approaches to processing and utilization. These extracts hold potential applications for various food products such as beverages, gels, sauces, or emulsions, contributing to the reduction in waste and the creation of value-added products from mango residues.

Mango Peels as an Industrial By-Product: A Sustainable Source of Compounds with Antioxidant, Enzymatic, and Antimicrobial Activity

“…The two curves are generally comparable after excessive evaporation of moisture in the fresh peels, indicating a similar composition. The residue represents the ash fraction, which contains minerals that cannot be degraded [46]. The residue accounted for 8.0% of the fresh peels and 26.7% of the dried peels, based on the total mass of the studied peel samples.…”

“…Moreover, the two curves of fresh and dried mango peels do not differ further. The second peak (198-254 • C) and the third peak (304-368 • C), shown as exothermic peaks, are due to the degradation of longchain, high-molecular-weight polymers [46] or various salts, for example, sulfur-containing salts, such as sodium hydrogen sulfite. Sodium hydrogen sulfite, which decomposes at 315 • C, is classified as a food additive [49].…”