Cassava Starch Thermoplastic Packaging: A Systematic Evidence Map of Additive and Property Relations for Water Affinity and Mechanical Performance

Cassava thermoplastic starch (TPS) is a renewable candidate for short-life biodegradable packaging, but high water affinity, moisture-dependent mechanical behavior, and limited barrier performance constrain its use. A manual PRISMA-guided systematic review of Scopus and Web of Science (1996–2025; 312 records) was conducted according to strict criteria (standardized tensile testing, ≥70 wt% cassava starch, and mean ± SD reporting). Tensile strength, extracted from 14 eligible studies (92 film formulations), had medians of 2.2 MPa (interquartile range, 1.0–3.9 MPa; 11 studies) for unmodified glycerol-plasticized films and 2.7 MPa (1.5–5.0 MPa; 13 studies) for formulated films, indicating a substantial mechanical gap relative to conventional packaging polymers such as polyethylene (15–40 MPa) and PLA (50–70 MPa). A computer-assisted evidence map of 934 Scopus records, with automated triage, full-text extraction, and topic modeling, describes how visible formulation–property relations are in the literature rather than their magnitude. The evidence shows that formulation routes cannot be ranked by isolated property gains: plasticization improves processability and ductility but may increase moisture sensitivity, whereas reinforcement, chemical modification, and blending improve selected properties with formulation-dependent trade-offs. Cassava TPS should therefore be engineered as an application-matched property portfolio. Comparability remains limited because conditioning, thickness, processing history, test methods, uncertainty, and food-contact validation are inconsistently reported.