Influence of germination and pulse type on texture of high moisture meat analogs

Enhancing the texture profile of high moisture meat analogs (HMMAs) presents a notable challenge, one that can potentially be addressed by diversifying the ingredients used. This research examines how the type of pulse specifically peas and lentils - and the germination process can impact the functional properties and structural transformation of proteins within these ingredients. A twin-screw extrusion cooking process was used to produce HMMAs with an optimized screw speed of 800 rpm and a final zone temperature of 140 degrees C. The quality of the HMMAs was evaluated through an analysis of their textural properties and Scanning Electron Microscopy (SEM). Generally, germination and variations in pulse types were seen to create significant (p < 0.05) changes to the protein profile. These changes resulted in reduced subunit molecular weight, altered melting temperatures (120-127 degrees C), and increased quantities of disulfide bonds. In turn, these shifts elicited corresponding adjustments in the HMMAs when subjected to identical extrusion conditions. Notably, the protein-rich fraction derived from lentils was markedly different (p < 0.05) from that of peas, contributing to lower levels of cohesiveness, chewiness, and gumminess in HMMAs. SEM images taken at 250 x -1000 x magnification demonstrated filaments in HMMAs, illustrating the transformation of proteins from a globular to a fibrous form. Guided by the influence of melting temperature and shear force on pulse protein, the "Thermo-shear Protein Structuring Principle" was proposed. Overall, our findings offer critical insights into how germination and pulse selection can affect protein behavior during the production of HMMAs.