Investigation of the changes in gelation properties of hydroxypropyl distarch phosphate-surimi gel under different gelation-freezing treatments.

BACKGROUND: Frozen storage often leads to quality deterioration of surimi-based products. At present, most of the research focuses on improving the quality of surimi products by adding cryoprotectants, and there are few studies available on preparation technology. Therefore, the effects of different gelation-freezing treatments, high temperature heating-freezing treatment (HF), low temperature heating-high temperature heating-freezing treatment (LHF) and low temperature heating-freezing-high temperature heating treatment (LFH) on the quality changes of surimi gels containing hydroxypropyl distarch phosphate (HPDSP) during frozen storage were investigated. RESULTS: With the extension of frozen storage time, the quality of surimi gel in all groups decreased, but the quality of surimi gel with HPDSP was better than that of surimi gel without HPDSP. Compared with HF and LHF, the change range of breaking force, hardness, gumminess, whiteness and disulfide bond content of HPDSP-surimi gel treated with LFH was the least during the frozen storage. In the reheating process of LFH, HPDSP could absorb the water lost during freezing. Therefore, the change in the transverse relaxation time of HPDSP-surimi gels treated with LFH was smaller, with more immobile water and less free water and P22 of 96.81% and P23 of 0% at 16 weeks. In addition, the breaking deformation, cohesiveness, resilience, springiness and protein composition of surimi gels with and without HPDSP treated with HF, LHF and LFH did not change significantly during frozen storage. CONCLUSION: The combination of LFH and HPDSP could effectively reduce the quality change of surimi gel during frozen storage. © 2023 Society of Chemical Industry.

Ovalbumin/sodium alginate Pickering emulsion: Structural characteristics and its contribution to enhancing the gel properties of Hairtail (Trichiurus haumela) surimi.

In this study, ovalbumin (OV) and sodium alginate (SA), two macromolecular complexes, were coagulated into the emulsifier (OV/SA), which stabilized soybean oil by electrostatic interaction, hydrophobic interactions, and hydrogen bonding. The structure of OV/SA and properties of OV/SA Pickering emulsion were investigated. Additionally, the effect of emulsions on the gel and protein properties of hairtail surimi was studied. The results revealed that with the increasing concentration of OV/SA, the particle size and zeta potential value (negative value) of the emulsion initially decreased and then increased, while the rheological properties gradually improved. Compared with the surimi gel directly supplemented with soybean oil, the addition of emulsion enhanced gel strength, whiteness, water holding capacity, and hydrophobic interactions, resulting in a more stable gel network structure. In summary, incorporating emulsion into surimi at the same lipid content not only maintained its gel properties but also improved its color and compensated for lipid loss.