High moisture extrusion cooking on soy proteins: Importance influence of gums on promoting the fiber formation.

The influence of gums on the quality of extrudates prepared by the high moisture extrusion cooking of soy protein was studied. Three food gums, iota carrageenan (ICGN), carboxymethylcellulose sodium (CMC) and sodium alginate (SA), were investigated for their effects on promoting the fiber formation of extrudates. Results obtained indicated that lamellar structures were formed at the cooling zone for samples containing 6% CMC and 6% SA. The addition of 6% SA enhanced the quality of extrudates, such as improved rehydration rate and digestion rate. Furthermore, interactions between protein molecules over the extrusion process were also analyzed, and the importance of the type of molecular bonds responsible for the formation of extrudates was determined to be: disulfide bonds ≥ hydrogen interactions > hydrophobic interactions. Results of this work would be of importance in the design of meat analogs using soy protein concentrate, and more importantly, in the understanding of protein-protein interactions during extrusion for sustainable health.