ABSTRACT
This study investigated effects of carboxymethylcellulose sodium (CMC) on the conformational evolution of pea protein during the high moisture extrusion process. The morphological observation showed that the addition of CMC facilitated the formation of fibrous structure of pea protein. In comparison with the pea protein in the melting zone and extrudate, the combination of CMC increased the denaturation enthalpy of pea protein by 2.09 % and 2.34 %. Compared with the material in the mixing zone, the degree of grafting between CMC and pea protein in the die was enhanced by 98.95 %. In general, the supplementation of CMC depressed the exposure of hydrophobic groups in the pea protein. In the extrusion barrel, the CMC increased the unfolding of protein molecular chains while it promoted the refolding of protein chains in the die. For the extrudate, the addition of CMC decreased the contents of α-helix and ß-sheet of pea protein by 9.67 % and 6.93 % while the contents of ß-turn and random coil were increased, leading to changes in the molecular weight distribution of protein molecules. In conclusion, these results provided new strategies toward producing the high-quality pea protein-based meat analogues by adding CMC.
ABSTRACT
Rice Bran (RB) was added to soybean protein isolate (SPI) at 0%, 5%, 10%, 15% and 20% as addition to produce simulated meat by high moisture extrusion, and the apparent properties and structural characteristics of RB-SPI simulated meat were studied. The addition of 10% RB weakened the interaction among hydrogen bond (HB), hydrophobic bond (HI) and disulfide bond (DB), further increasing the hardness of simulated meat. Meanwhile, it decreased the content of intermolecular hydrogen bonding and enhanced the interaction between HI and HB, resulted in an increased tension. Adding 5% RB weakened the interaction between HB, HI and DB, decreased the content of random coils in the secondary structure, but strengthened the DB and ultimately increased the thermal stability of simulated meat.
