Study on the mechanism of protein-polysaccharide complex high viscosity gel and its adhesion in plant meat substitute.

This study prepared high viscosity food gels using soybean protein isolate (SPI), coconut oil, potato starch (PS), and Konjac glucomannanone (KGM) to explore the adhesive properties of the gel between the texturized proteins (one of the components of plant meat substitute). The changes in the colloidal properties containing different PS and KGM concentrations were examined by adjusting the ratio to improve the viscosity, texture, and taste of the gel, while the mechanical, rheological, thermal, and microstructural properties were also comprehensively evaluated. The apparent viscosity test, tensile test, and plane observation indicated that the sample containing 7 % PS and 1.5 % KGM (P7K1.5) displayed the highest viscosity after stretching. SEM analysis indicated that the P7K1.5 sample exhibited a relatively uniform structure. After unfolding, the aggregation of protein chains resulted in a dense protein-polysaccharide gel network structure with KGM. The PS aggregates coalesced to create a continuous viscous network structure. DSC results indicated that the sample exhibited the highest melting point temperature of about 139 °C and optimal thermal stability. In conclusion, the P7K1.5 sample yielded the best results in plant meat substitute assembly and other test indexes. These findings establish a theoretical foundation for the research and development of high viscosity food gels, promoting their utilization in plant meat substitute.