Effect of ultrasound assisted treatment and microwave combined with water bath heating on gel properties of surimi-crabmeat mixed gels

Abstract

Crabmeat from Chinese mitten crab (Eriocheir sinensis) has unique flavor and high nutritional value, which make it a useful ingredient in surimi products. To promote the manufacture of surimi-crabmeat mixed gels, we investigated the effect of ultrasound treatment and microwave heating, combined with water bath heating on gel properties. Replacing the second step with microwave heating, in the traditional two-step heating process, significantly increased the deformation and decreased the breaking force of mixed gels. Additionally, microwave heating promoted the aggregation of myosin heavy chains and the formation of high-molecular weight polymers, and improved water holding capacity. However, owing to rapid heating, microwaving led to moisture loss of mixed gels. Raman spectrum analysis indicated that microwave heating increased the α-helical content and decreased β-sheet content, while ultrasound and the addition of crabmeat had minimal effect on the secondary protein structure. Crabmeat conferred better water holding capacity and higher increment of moisture content to surimi gels but led to coarser surface morphology. Ultrasound improved the increment of moisture content and surface morphology. These results suggested that ultrasound and microwave could be used as efficient ways to improve gel properties of mixed surimi gel products.