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This work proposes an advance towards the scaling of biodegradable films based on corn starch and chitosan, considering the relevant film properties that condition their use for food packaging and their economic feasibility. The influence of corn starch: chitosan (CS:CH) proportion and chitosan molecular weight used in the formulation is also studied. Chitosan (CH) addition improves film forming dispersions (FFDs) stability stored under refrigerated conditions and enhances the film UV barrier properties and elongation at break, however material costs are higher. Films with higher starch content exhibited higher elastic modulus and tensile strength. Water vapor barrier, heat‐sealing capacity, and sealing resistance also increase with the corn starch (CS) proportion in film formulation. Taking into consideration the chitosan type used, the polymer‐plasticiser and polymer‐solvent interactions prevail and led to the development of more flexible materials in film formulations with low molecular weight chitosan (LMW‐CH). Meanwhile, polymer‐polymer interactions also became relevant in those obtained with MMW‐CH leading to resistant films. The obtained results indicate that composite films could be used in food packaging design, with those formulated with 75% CS and 25% medium molecular weight chitosan (MMW‐CH) being a good option considering both the film's properties as well as its economical feasibility.

Blueberries are highly appreciated for their high antioxidant content but are also particularly susceptible to fungal deterioration. In this work, corn starch and chitosan, byproducts of the fishing industry, as well as active compounds obtained from citrus processing waste were used to obtain active biodegradable film packaging. Blueberries were packed in corn starch–chitosan (CS:CH) films and in active films containing lemon essential oil (LEO) or grapefruit seed extract (GSE). The effects of film packaging on the quality parameters of berries and the fungal incidence of disease during storage were studied and compared to benchmark materials. A conservation assay simulating transport and commercialization conditions was conducted. Blueberries packed in CS:CH films showed antioxidant capacity values closer to those packed in commercial PET containers (Clamshells), preserving 84.8% of the initial antioxidants content. Fruit packed in LEO films exhibited the greatest weight loss and rot incidence, and poor surface color. CS:CH and GSE films controlled the fruit respiration rate and weight loss, therefore they are materials with adequate barrier properties for blueberries conservation. Bags formulated with GSE showed adequate barrier properties to maintain fruit quality attributes without the incidence of rottenness, being an interesting option for blueberries exportation.