Effects of freeze-dried Ecklonia cava hot water extract as a gel enhancer for fried fish cakes with threadfin bream (Nemipterus spp.) surimi

In the present work, we used threadfin bream (Nemipterus spp.) surimi fish cakes to test the viability of freeze-dried Ecklonia cava hot water extract (ECWE) as a gel enhancer. The effects of freeze-dried ECWE on the gel strength and the colour of the fish cakes were investigated. The gel strength increased in fish cakes incorporated with 0.5% freeze-dried ECWE as compared to the control (no ECWE). The lightness and whiteness values of samples containing ECWE were lower than those of the control samples. Scanning electron microscopy (SEM) observations of fish cakes containing 0.5% freeze-dried ECWE exhibited a finer and more continuous matrix as compared to the control samples. Incorporating 0.5% ECWE improved the gel strength, and produced high-quality emulsions with a finely distributed gel network due to the presence of mannitol and some polyphenolic compounds in freeze-dried ECWE. The use of freeze-dried ECWE in the production of fish cakes is effective as a natural gel enhancer for surimi-based products.