Concentration-dependent CO2 injection modulating porous structure and physicochemical properties in plant protein-based meat analogues.

This study presents the investigation of CO2 injection as a strategy to modulate the structural and textural properties of meat analogues. The effects of different CO2 injection concentrations (0.1, 0.2, 0.3, 0.4, and 0.5 wt%) were systematically examined. The results revealed that the injection of CO2 enhanced the expansion ratio, porosity, and water absorption capacity of the extrudates, while reducing their hardness. Notably, extrudates produced with 0.4 wt% CO2 exhibited a hardness similar to cooked beef, while those with 0.5 wt% resembled the hardness of cooked chicken. In addition, at concentrations below 0.2 wt%, the generated pores were small and evenly distributed. In contrast, concentrations above 0.2 wt% led to the formation of larger pores and a higher mass flow rate, which further influenced the molecular structure of the extrudates. These findings highlight the potential of CO2 injection as a promising strategy for improving the quality of meat analogues.