Effect of surimi quality on properties of edible films based on Alaska pollack

Transparent and flexible edible/biodegradable films were successfully made from frozen Alaska pollack surimi. The effects of surimi quality on film formation, tensile strength (TS), elongation at break (EAB), water vapour permeability (WVP), light transmission, transparency, film solubility, protein solubility, and enzyme hydrolysis of surimi films were investigated. Thawed Alaska pollack surimi was incubated at 30 °C for 20 min (slight protein denaturation) and at 30 °C for 5 h (complete protein denaturation) in order to intentionally lower the surimi quality. Slight protein denaturation caused decreased EAB of the films and the complete denaturation gave rise to reduction of TS and EAB. The remaining of film properties were not markedly influenced by the loss of surimi quality. Hydrogen bonds, together with ionic bonds, played an important role in the formation of surimi films, but hydrophobic interactions were more involved when surimi with complete protein denaturation was used for the film preparation.