The characteristics of gelation of myofibrillar proteins combined with salt soluble Rhodotorula glutinis proteins by enzymatic crosslinking

Some microbial single-cell proteins are capable of producing synergistic crosslinking interactions with edible proteins by rational regulation. Herein, we reported that salt soluble proteins (RGP) extracted from Rhodotorula glutinis in an alkaline and saline system may combine with myofibrillar proteins (MP) by transglutaminase (TG) polymerization to form improvable irreversible thermal co-gels. The combination of M P , RGP, and TG, namely restructured M P gels, led to significantly enhanced water holding capacity (WHC), up to 90.76 +/- 1.88% (% of retained water) and textural properties (hardness, springiness, and adhesiveness) as well as decreases of 'gauchegauche-gauche' S-S bonds and alpha-helix conformations and increases of 'gauche-gauche-trans' S-S bonds and beta-fold conformations, compared to MP and MP-RGP groups. Differential scanning calorimetry analysis validated that thermostability of myosins and actins from MP was reduced after using RGP, TG, and their combination, and unfolding and denaturation of myosin occurred easily during thermal co-gelation by TG and/or RGP.

Automated summary

Microbial single-cell proteins can create synergistic crosslinking with edible proteins through rational regulation. Salt soluble proteins extracted from Rhodotorula glutinis may combine with myofibrillar proteins through transglutaminase polymerization to form improved irreversible thermal co-gels, enhancing water holding capacity and textural properties while altering protein structures. The thermostability of myosins and actins in myofibrillar proteins decreases when combined with salt soluble proteins and transglutaminase.