Cassava Starch for Sustainable Food Systems: Recent Advances in Processing Technologies and Structure–Function Relationships

Cassava (Manihot esculenta Crantz) starch is a promising renewable food ingredient for sustainable food systems because cassava combines high adaptability, climate resilience, and versatile starch functionality. However, its sustainability potential cannot be evaluated solely from crop productivity or starch recovery, as substantial water and energy requirements, postharvest physiological deterioration, processing losses, wastewater generation, and residue management remain important challenges. This review critically examines recent advances in cassava starch production and processing from a sustainability and structure–function perspective. Conventional wet extraction is compared with emerging green approaches, including ultrasound-, microwave-, and enzyme-assisted extraction, clean-label physical and enzymatic modification, fermentation, energy-efficient drying, water and wastewater management, and circular valorization of cassava processing residues. Genotype, environment, harvest and postharvest conditions, and processing technologies influence the hierarchical organization of starch, including amylose and amylopectin architecture, chain-length distribution, molecular size, crystalline order, lamellar organization, and granule characteristics. These structural attributes collectively determine pasting, gelatinization, rheological and gel behavior, retrogradation, freeze–thaw stability, and starch digestibility, thereby defining suitability for specific food applications. Building on these relationships, this review proposes a structure-directed sustainability framework in which starch is not simply produced with fewer resources but is deliberately designed to deliver target functionality with minimum processing and environmental burdens. This perspective supports application-specific design of cassava starch for conventional, gluten-free, health-oriented, and emerging food systems while enabling higher-value utilization and circular management of processing residues.