Turmeric essential oil‐loaded wheat starch cryogels as superabsorbent pads for active packaging of fish fillets

BACKGROUND: This study aimed to create a cryogel with water-absorbing and antioxidant properties. Wheat starch (10%, w/v) was used to produce cryogels, which were then incorporated with turmeric essential oil (TEO) at two concentrations: 20% and 30% (w/w of starch). The production method consisted of gelatinization, freeze/thaw cycles, and subsequent freeze-drying. The materials were applied as an absorbent pad for fish fillet exudate. The major compounds of TEO were ar-turmerone (43.60%) and α-turmerone (23.49%), characterized by gas chromatography. RESULTS: ) and high porosity (85.97%), not differing among the formulations. The water absorption capacity was high, with the control (0% TEO) reaching 1026% and reducing for those with TEO to approximately 883%. Cryogels demonstrated a high TEO loading capacity, exceeding 90%. In vitro release showed that, after 2880 min, the 30% TEO cryogels released 22% of their content in a hydrophilic medium and a substantially higher 69% in a lipophilic medium. The cryogels with 30% TEO achieved an antioxidant activity of 48% for ABTS [i.e. 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)] radical inhibition and 23% for DPPH (i.e. 2,2-diphenyl-1-picrylhydrazyl) radical. When applied to fish fillets, after 7 days of storage, the cryogels maintained stable pH (6.06) and mass loss (5.6%) across treatments, at the same time as showing a comparable exudate absorption of approximately 35%. CONCLUSION: Exhibiting water-absorbing capacity, high loading capacity, controlled in vitro release, and antioxidant activity. The developed materials are promising three-dimensional materials for active food packaging applications in fish fillet preservation.