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Following the new eco‐friendly technologies for food packaging, biodegradable composites with edible components as starch, glycerol, and lentil flour rich in fiber (0, 0.5 wt.% and 1.0 wt.%) are developed. The lentil flour, obtained from the residue of a commercial lentil protein extraction process, have micrometer size and, unlike typical lentil flour, have three times higher concentration of fiber. Its use leads to increments in the storage modulus, strength at break, and toughness of the composites, and to decreases in water vapor permeability, with respect to the matrix, showing that the additive can act as reinforcement for starch films. Composites with 0.5 wt.% of flour result in more flexibility due to their homogeneous dispersion in the matrix. All films are thermally stable up to 240 °C and biodegradable in vegetal compost after 4 weeks. These new composites are high promising for use as biodegradable and edible food coatings. They could enrich food nutritional value by the fiber‐rich flour addition.

Starch constitutes a promising resource for biodegradable packaging, but it presents several processing drawbacks when using conventional industrial equipment, such as flat‐die extrusion. This work demonstrates that the replacement of native cassava starch (NS) with commercial hydrolyzed (HS) or carboxymethyl (CMS) starches diminishes the amount of energy required to process starch granules into thermoplastic films by extrusion. Homogeneous films with starch‐glycerol interaction improvements are obtained when using HS or CMS instead of NS. HS films exhibit the lowest crystallinity and the highest susceptibility to water among the studied systems. Likewise, CMS films maximize Vh crystalline structure fraction and present higher Young's modulus and stress at break, and lower water vapor permeability values. In order to combine the positive properties and to overcome the limitations of each modified starch, blend films from HS:CMS (50:50 wt%) are also developed and investigated. Phase separation is observed in this system, and there are no improvements in the overall properties. The results of this investigation show that employing commercial CMS, even in very low carboxymethylation degree represents a successful strategy to improve mechanical and barrier properties of flat‐die extruded films, while HS can be used to obtain water‐soluble films for specific applications.

Obtaining edible and biodegradable films for food packaging applications has been a strong desire of consumers, scientific community and industry for years. In this context, edible films from cassava starch with wheat or oat bran (0, 5 and 10 wt.%) manufactured from an industrially established process for packaging, such as extrusion technique, are investigated. Wheat bran is found to have a high content of total dietary fiber, being able to provide a nutritional contribution to the packaging and to consumers. Some broken bran grains smaller than 1 µm are observed, distributed quite homogeneously in the matrix and without the presence of phase separation, suggesting great miscibility between the components. Brans acted as reinforcement in concentrations of 10 wt.%, leading in thecase of wheat bran to increases of 850%, 45% and 25% in Young modulus, strength at break and toughness, respectively, and to decreases in moisture content. The incorporation of bran not significant change the thermal stability and biodegradation of the films. This investigation showed that biodegradable and edible cassava starch-based films can be manufactured by a scalable process with possible improvements in nutrition and mechanical strength using 10 wt.% of bran for its potential employ as food packaging.