Sustainable starch-based cryogels enriched with phenolic compounds extracted from cashew apple bagasse by subcritical water for active food packaging applications.

Abstract

Using agro-industrial residues with effective technologies is key to advancing a circular bioeconomy. This study proposes the use of phenolic compounds extracted from cashew apple bagasse for green technology applications (subcritical water) and their incorporation into wheat starch cryogel. The cryogels were extensively characterized in terms of morphology, physical-chemical, mechanical, thermal, and structural properties, along with their in vitro release behavior and application in food matrices of vegetal (arugula leaves) and animal (chicken breast) origin. The findings revealed cryogels possessing a range of pore sizes and shapes, characterized by low density (0.071-0.081 g cm-3) and high porosity (88.2-89.5%). Cryogels containing phenolic extract maintained their water absorption capacity, showed an increase in solubility, and a reduction in syneresis from 512.2% to 382.0%. indicating improved structural integrity. Extract-loaded cryogels had lower compressive strength than the control, but they remained intact when swollen, making them suitable for moisture-sensitive packaging applications. In vitro release studies showed rapid release in both hydrophobic and hydrophilic simulant food, indicating cryogels could be used in more perishable foods. Cryogels with 5% phenolic extract reduced mass loss and G-value degradation (shown in green) in arugula leaves, while cryogels were not very effective at controlling pH increase in chicken breast. These findings underscore the significance of customizing cryogel formulations to meet the specific needs of plant-based or animal-based foods, the food industry's aim to prolong product shelf life, along with designing smart packaging that supports a circular bioeconomy and minimizes environmental impacts.