Effects of the hydration state of psyllium husk on the gel properties of pork meat batters under 50% phosphate reduction: Protein molecular interactions and lipid conformational alterations

Abstract

The effects of two hydration states (dry powder versus prehydrated gel) of psyllium husk on the gelation properties of pork meat batters with a 50% reduction in sodium tripolyphosphate content were investigated. The results revealed that both forms of psyllium husk significantly improved the water- and fat-binding abilities and textural characteristics of phosphate-reduced pork meat batters (P < 0.05). Moreover, the prehydrated gel outperformed the dry powder in most gel quality indicators, thereby enabling the reduced-phosphate formulations to attain gel properties comparable to those of the high-phosphate control. The prehydrated gel of psyllium husk augmented the adsorption of myofibrillar proteins onto fat surfaces, reinforced protein hydrogen and disulfide bonding, increased the degree of myosin denaturation, promoted the formation of trans-gauche-trans disulfide conformations, and induced interchain vibrational coupling and acyl chain disordering in lipids. These molecular alterations may have contributed to the formation of a protein gel matrix with enhanced structural coherence, featuring uniformly dispersed small fat particles. Therefore, psyllium husk (particularly its prehydrated gel) emerges as a promising "clean-label" ingredient for phosphate replacement in meat products.

Keywords: Lipid conformation; Molecular force; Phosphate replacement; Prehydration; Psyllium husk; Regulatory mechanism.