Development of Biodegradable Films From Wheat Flour: A Comparative Study Between Soft and Hard Wheat and Impact of Cysteine and Glutamine

The study's main objective is to evaluate and compare the creation of biodegradable films from soft wheat flour and durum wheat flour, as well as to examine the effect of the addition of cysteine and glutamine on the structure and functional properties of said films. Soft wheat flour (SWF) and durum wheat flour (DWF) were used to prepare biodegradable films, with the incorporation of additives such as cysteine and glutamine (0.02 w/w), and the properties in color and brightness, opacity, thickness, internal transmittance, moisture content, and water solubility, water absorption capacity, contact angle, water vapor permeability, mechanical properties, thermal properties, and microstructure were evaluated. The results indicate that DWF films maintained their characteristics better under humidity and temperature conditions, and SWF, although more flexible, presented limitations in their thermal and mechanical stability. The addition of cysteine and glutamine in DWF significantly increased the flexibility and thermal stability of the films. Among the formulations, DWF‐C films exhibited the highest tensile strength (3.9 MPa) and elastic modulus (240 MPa), confirming the reinforcing effect of amino acid incorporation. Thus, due to its higher gluten content, DWF demonstrated superior mechanical and thermal properties to SWF, which contributes to a more rigid and resistant structure. Therefore, DWF is the most suitable option for high‐strength and stability applications. At the same time, SWF could be useful in contexts that prioritize flexibility.