Agricultural and Food Waste Valorization for Bioplastic Production: A Comprehensive Review

Conventional plastics derived from fossil resources have created severe environmental and waste‐management problems, including long persistence in landfills, microplastic pollution, and high greenhouse gas emissions. Bioplastics produced from agricultural and food waste offer a promising alternative that simultaneously addresses plastic pollution and biomass disposal. This review synthesizes the findings of 15 experimental studies on the production of polyhydroxyalkanoates (PHAs, including PHB and PHBV), starch-based plastics, cellulose acetate, and extracellular polymeric substance (EPS) films using fruit and vegetable residues, lignocellulosic crop wastes, and agro-industrial byproducts. Feedstocks such as potato, orange, banana, apple, pomegranate, and melon peels, as well as wheat bran, flax fibers, and cotton linters, were evaluated in terms of chemical composition, pretreatment requirements, fermentable sugar release, microbial conversion, and final polymer properties. Physical, chemical, and biological pretreatment strategies are compared, with an emphasis on inhibitor formation and enzymatic hydrolysis efficiency. Reported PHB contents range from approximately 50% to 75% of cell dry mass, while cellulose acetate yields from flax residues exceed 80%, and EPS-based peel films exhibit suitable barrier and antimicrobial properties for food-contact applications. The review also discusses the implications of the circular bioeconomy, techno-economic constraints, and research needs for scaling waste-to-bioplastic processes. Overall, the literature demonstrates that properly pretreated agricultural and food waste streams can be transformed into competitive bioplastic materials and should be considered in future sustainable waste management strategies.