Compositional and Bioactive Characterization of Industrial Fruit Wastes in Sri Lanka

The potential of industrial fruit processing wastes for nutritional and bioactive applications was evaluated. A survey of four major fruit processors in Sri Lanka identified pineapple (Ananas comosus), mango (Mangifera indica L.), papaya (Carica papaya), and passion fruit (Passiflora edulis) as the most processed fruits, generating waste yields of 69.98%, 50.07%, 48.41%, and 61.21%, respectively, primarily as peels, seeds, and bagasse. Analysis of dehydrated wastes revealed crude protein (0.50-25.94%), crude fat (0.36%-28.16%), and crude fiber (12.97-43.10%). Essential minerals (K, Ca, Mg, Zn, Cu) were present, while toxic metals were mostly below permissible limits. Phytochemical evaluation showed total phenolic contents of 1.85-9.47 mg Gallic Acid Equivalents/g and flavonoids of 1.38-21.82 mg Rutin Equivalents/g. Total antioxidant capacity ranged from 1.85-25.54 mg Ascorbic Acid Equivalents/g, and DPPH radical scavenging activity (IC₅₀) ranged from 0.53-54.18 mg Acetic Acid Equivalent/mL. Mango and papaya peels, along with mango seed kernels, exhibited the highest antioxidant activity, consistent with their phenolic and flavonoid levels. These results indicate that industrial fruit wastes are nutrient- and bioactive-rich materials, offering significant potential for functional food and nutraceutical applications, contributing to waste valorization and sustainable food processing.