Carrageenan/Gallic Acid Blend Hydrogel Films for Potential Use as Natural Moisture Scavengers in Active Food Packaging

One of the primary focuses in food technology is to extend the shelf life of food products using active food packaging materials. In this study, carrageenan-gallic acid blend hydrogel films were prepared by the casting method, proposed as a new hydrogel film composition to be used as a moisture scavenger. The structural and morphological characterization of the films was performed along with mechanical, thermal, and swelling analyses. Moisture absorption tests revealed that gallic acid was highly effective on the moisture uptake capacity of carrageenan hydrogels, increasing this value to approximately 80% compared to pure carrageenan film at high relative humidity (90%) and temperature (50 °C), which are critical conditions in food storage. Moreover, moisture absorption kinetics revealed that carrageenan-gallic acid blend films possessed greater theoretical moisture absorption capacities. Overall results suggest that natural carrageenan-gallic acid blend hydrogel films have promising potential as moisture scavenger absorber pad materials in active food packaging.