Sodium alginate-combined ultrasonic modification of starch: Structural characterization, batter properties, and crispiness improvement in fried fish.

Sodium alginate-combined ultrasonic (SA-US) modification of wheat flour and corn starch was characterized to investigate its effects on batter properties and fried fish crispiness. This modification significantly increased hydration properties, and gelatinization temperature of wheat flour and corn starch (P < 0.05), while decreasing short-range structure, double helices, crystallinity, and starch granules' integrity. Further, addition of SA-US-modified wheat flour and corn starch to the batter increased viscosity, G', G", and bound water, which improved batter pick-up and adhesion to the fish. The fried battered fish containing SA-US modified starch exhibited increased water content, L*, b*, crispiness, overall acceptability, and decreased oil content, a*, volumetric shrinkage, and frying loss. The hardness, crunchiness, and crispiness of products with SA-US-modified starch were enhanced by 44.3 %, 58.2 %, and 52.7 % after post-fry holding for 60 min, respectively. The study offers new insights into hydrocolloid-combined ultrasonic modification of starch for enhancing the quality of fried foods.