Impact of Myofibrillar Protein Emulsion With Different Pre-Emulsified Soybean Oil Contents on the Freeze–Thaw Cycles Characteristics of Surimi Gel

Abstract

The research examines how myofibrillar protein emulsion with different pre-emulsified soybean oil (PESO) levels (0%, 6%, 8%, and 10%) influences surimi gel across seven freeze–thaw (F-T) cycles. The addition of PESO led to a notable improvement in gel strength and whiteness. Significant increases were also noted in hardness, water-holding capacity (WHC), and the maximum relaxation time of the immobilized water (p < 0.05). The findings revealed an increase in both the storage modulus (G′) and the loss modulus (G″), while secondary and microstructural assessments demonstrated a stronger and more organized gel network. As the gel was subjected to successive F-T cycles, its overall quality declined progressively. An increase in the number of F-T cycles resulted in a steady decrease in gel hardness, WHC, gel strength, and lightness; however, there was no significant change in gel springiness (p > 0.05). Notably, when the soybean oil concentration in the pre-emulsion was set at 8%, the surimi achieved optimal G′, hardness, and gel strength after enduring seven F-T cycles, with its WHC peaking at a significant 76%. The findings demonstrate that the addition of PESO effectively improves surimi gel properties and mitigates lipid loss during rinsing, providing insights for enhancing surimi product quality.