Enhancing frozen fish quality through polysaccharide-ice glazing: Insights from physical properties and preservation effects

Abstract

Polysaccharide ice-glazing is a widely employed method for preserving frozen fish, with the choice of polysaccharide playing a crucial role in preservation effectiveness. This research investigates the impact of various polysaccharides, including neutral polysaccharides like konjac glucomannan (KGM) and pullulan (PUL), as well as ionic polysaccharides such as gellan gum (GG), κ-carrageenan (KC), carboxymethyl cellulose (CMC), and xanthan gum (XG), on the physical properties of ice. Additionally, we assess the influence of polysaccharide ice-glazing on the quality of frozen snakehead (Channa argus) fish fillets. Our study shows that the physical properties of polysaccharide-infused ice are affected by both polysaccharide type and concentration. Increasing the polysaccharide concentration led to a reduction in water activity within the supercooled polysaccharide solution. Additionally, the characteristics of ice formed by the polysaccharide solution, including ice crystal size, compressive strength, sublimation rate, and oxygen permeability, consistently decreased. In our comparative analysis, at equivalent polysaccharide concentrations, the PUL solution exhibited the lowest water activity. Notably, PUL-ice demonstrated superior performance, displaying the smallest ice crystal size, highest compressive strength, lowest ice sublimation rate, and the most effective oxygen permeability barrier. Following this in decreasing order of performance were the GG, KC, CMC, XG, and KGM samples. Moreover, when applied to glazing snakehead fish fillets, pullulan ice-glazing outperformed KGM ice-glazing in preserving fish quality, confirming the direct influence of polysaccharide-induced ice properties on fillet preservation outcomes. This study provides essential insights to guide informed decisions in the field of polysaccharide ice-glazing applications, aimed at enhancing the quality of frozen fish.