Effect of γ-Oryzanol+β-Sitosterol-based Oleogels on the Gel and Digestive Properties of Nemipterus virgatus Surimi

In order to investigate the effect of γ-oryzanol+β-sitosterol-based oleogels on gel and in vitro digestive characteristics of surimi, oleogels were prepared using different unsaturated vegetable oils (soybean oil, sesame oil, corn oil, flaxseed oil, camellia oil) and γ-oryzanol+β-sitosterol. The effects of different vegetable oils and oleogels on gel strength, water holding capacity, in vitro protein digestibility and antioxidant capacity of surimi were compared. The results showed that the addition of vegetable oil reduced the gel strength, water holding capacity and in vitro digestibility of surimi, and increased the particle size of in vitro digestion products. However, the strength, water holding capacity and antioxidant capacity of surimi gel added with oleogels significantly increased compared to the corresponding vegetable oil group. In addition, the addition of oleogels could promote the formation of a more compact and uniform gel network structure, reduce the binding site of myofibrillar protein and protease, and decrease the protein digestion. Among them, the strength and digestibility of surimi gel added with flaxseed oil-based oleogels were the highest, which were 3936.067 g·mm and 75.89%, respectively. The digestive fluid also contained more beneficial fatty acids to human body, such as α-linolenic acid, EPA, DHA. Therefore, the flaxseed oil gelatinized using γ-oryzanol+β-sitosterol can be added to surimi to improve the gel quality and enhance nutritional value of surimi products.