The Effect of Salt on the Gelling Properties and Protein Phosphorylation of Surimi-Crabmeat Mixed Gels.

Yajun Zhu,Jianfeng Lu,Shaotong Jiang,Yufeng Lu,Lin Lin,Tao Ye

doi:10.3390/gels8010010

Abstract

The effects of different salt additions (1.0%, 1.5%, 2.0%, 2.5%, 3.0%, and 3.5%) on the gelling properties and protein phosphorylation of the mixed gels (MG) formed by silver carp (Hypophthalmichthys molitrix) surimi with 10% crabmeat were investigated. The MG’s breaking force, deformation, gel strength, and water-holding capacity (WHC) increased as the salt concentration increased. The intrinsic fluorescence intensity of the samples initially decreased and then increased, reaching the lowest when the NaCl concentration was 2.5%. The result of SDS–polyacrylamide gel electrophoresis indicated that large aggregates were formed by protein–protein interaction in the MG containing 2.5% or 3.0% NaCl, decreasing the protein band intensity. It was also found that with the addition of NaCl, the phosphorus content initially increased and then decreased, reaching the maximum when the NaCl concentration was 2% or 2.5%, which was similar to the changing trend of actin band intensity reported in the results of Western blot. These results revealed that the amount of salt used had a significant effect on the degree of phosphorylation of the MG protein. The increase in phosphorylation was linked to improved gelling properties, which could lead to new ideas for manufacturing low-salt surimi products in the future.

Highlights

Surimi is a Japanese word and a term for concentrating myofibrillar protein, which is derived from the deossified material produced in fish that has been continuously washed and mixed with cryoprotectants [1]
We observed that NaCl addition significantly affected the surimi gels (SG) and mixed gels (MG)’s breaking force, deformation, and gel strength (Figure 1)
Gels 2022, 8, 10 force, deformation, and gel strength of SG gradually increased with the increase in salt concentration (1%, 1.5%, 2%, 2.5%, and 3%), but there was no significant difference (p > 0.05) in these properties of SG when the addition of NaCl was more than 3%

Summary

Introduction

Surimi is a Japanese word and a term for concentrating myofibrillar protein, which is derived from the deossified material produced in fish that has been continuously washed and mixed with cryoprotectants [1]. Silver carp (Hypophthalmichthys molitrix) is a common freshwater fish species in China, and its low cost makes it popular for commercial production. To increase the product’s added value, silver carp meat was processed into surimi products as low-fat and high-protein processed food. Surimi food, such as fish balls and crabsticks, is popular with consumers as a type of ready-to-eat food because of its nutrition, taste, and convenience [4]. After the addition of salt, surimi is chopped and heat-treated to form elastic gel products through the formation of protein networks by promoting covalent and non-covalent interactions [5]. High salt intake, according to the World Health Organization (WHO), has negative effects on blood pressure, thereby increasing the risk of cardiovascular diseases [8]

Methods

Results

Conclusion