## 4 Conclusions  
This study focused on starches derived from commonly cultivated crops in Kazakhstan, including cassava, potato, corn, wheat, pea, and rice. The physicochemical properties, structural changes, and thermal behavior of both native and thermally modified starches were systematically analyzed, aiming to provide a theoretical foundation and technical basis for the development of biodegradable film materials in Kazakhstan. The results demonstrated that starches from different botanical sources exhibited unique characteristics in terms of molecular structure, hydrophilicity, thermal properties, and biodegradability. High-molecular-weight starches such as cassava and potato showed excellent film-forming ability and mechanical stability, making them suitable for applications that require strength and durability, such as agricultural films and packaging materials. In contrast, wheat and rice starches, due to their rapid biodegradation, are  
Figure 5: X-ray diffraction (XRD) analysis (CSN—cassava native starch samples, CSM—cassava modified starch samples, PSN—potato native starch samples, PSM—potato modified starch samples, WSN—wheat native starch samples, WSM—wheat modified starch samples, CoSN—corn native starch samples, CoSM—corn modified starch samples, PeSN—pea native starch samples, PeSM—pea modified starch samples, RSN— rice native starch samples, RSM—rice modified starch samples). more appropriate for short-term or single-use biodegradable products. Pea starch, with its flexibility and moderate moisture resistance, is well suited for use in humid environments. Thermal modification significantly improved the thermal stability of all starch types, raising their glass transition and melting temperatures, reducing hydroxyl group reactivity, and enhancing structural compactness and moisture resistance. FTIR and DSC analyses confirmed the positive effects of thermal treatment on starch molecular structure and performance, validating the feasibility and practical value of this modification approach. Among all types analyzed, cassava starch stood out for its high amylopectin content, excellent elasticity, and strong film-forming capacity. After thermal modification, it showed significantly enhanced thermal stability and mechanical strength, making it a promising primary material for biodegradable films. Potato starch also exhibited outstanding water-binding capacity and structural integrity, especially after modification, although its brittleness may require the incorporation of plasticizers to improve flexibility. In conclusion, starches commonly available in Kazakhstan, particularly cassava and potato starches, hold strong potential for the development of biodegradable, eco-friendly film materials. This study offers a practical pathway for the high-value utilization of local starch resources and supports the advancement of a sustainable materials industry. It also lays the foundation for future research focusing on advanced formulation techniques, synergistic modification with functional additives, and the scale-up of industrial production. Conceptualization, M.M. and G.O. ; methodology, K.Z., Y.Y., K.S. and D.T. ; software, D.K., Y.Y. and Y.Z. ; validation, S.S. and K.A. ; formal analysis, M.M., I.T. and A.S.; investigation, K.S., D.T., I.T., A.S. and D.K. ; resources, Y.Z. and G.O. ; data curation, D.K., I.T. and A.S.; writing--original draft preparation, M.M. and K.Z. ; writing--review and editing, M.M. ; visualization, A.S. and I.T. ; supervision, G.O. ; funding acquisition, G.O. All authors have read and agreed to the published version of the manuscript. This research was funded by the Ministry of Agriculture of the Republic of Kazakhstan, grant number BR22883587 \"Improvement and development of high-tech technologies for deep processing of agricultural raw materials to strengthen food security in the Republic of Kazakhstan\". Not applicable. The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding author.