Waste not, want not: Comprehensive valorization of fruit and vegetable waste from single-product recovery to zero-waste strategies

The increasing volume of fruit and vegetable waste (FVW) has prompted growing interest in sustainable valorization strategies. This review introduces a structured framework to assess different valorization approaches including single-product, multiple-product, and zero-waste valorization (ZWV) of FVW. In the single-product approach, selected bioactive compounds such as polysaccharides, exopolysaccharides, and/or antioxidants are recovered, while the multiple-product strategy integrates co-extraction and sequential processing to enhance material utilization. The ZWV approach is presented as the most comprehensive model, aiming to eliminate final waste by combining green extraction methods, microbial bioconversion, and circular economy principles. The paper discusses both conventional and emerging extraction methods, highlights recent advances in combining extraction with fermentation, and reviews case studies demonstrating the production of compounds such as exopolysaccharides and single-cell proteins from residual biomass. Challenges related to industrial-scale implementation, including process complexity and economic feasibility, are also addressed. Furthermore, the manuscript outlines strategies for integrating ZWV across the food supply chain and emphasizes its potential environmental benefits. By providing a comparative analysis of valorization levels and a focused discussion on zero-waste implementation in the context of FVW, this study contributes a comprehensive perspective that may guide future research and industrial applications in sustainable biomass management.