Structural Properties, Mechanical Behavior, and Food Protecting Ability of Chickpea Protein-Derived Biopolymer Films

This study aimed to enhance the characteristic properties of chickpea proteins enriched with quercetin by incorporating whey proteins. For this, whey proteins were supplemented into the film systems at 10, 20, 30, 40, and 50% of the total protein content, and these formulations were labeled as CWF1, CWF2, CWF3, CWF4, and CWF5, in that order. Negative control (CF) was designed with chickpea protein alone. Essential amino acid content of chickpea protein (16.48%) was higher than that of whey protein (8.09%). FTIR spectra revealed protein-protein interactions occurred within film systems. Raising the whey protein content above 40% led to morphological issues in the films. Differences in moisture content, thickness, color, and opacity were obvious (p < 0.05). As the protein content boasted, a decrease in solubility and an increase in the swelling ratio of the films was detected (p < 0.05). CWF4 exhibited enhanced barriers and mechanical properties, followed by CWF3, CWF2, CWF1, CF, and CWF5 (p < 0.05). Moreover, in food simulators, quercetin release from films was monitored, and the highest release of quercetin occurred in 50% ethanol, followed by water and 95% ethanol. Ultimately, highly functional quercetin-loaded edible films, especially CWF4, stood out in protecting fresh strawberries.