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The effect and mechanism of myofibrillar protein (MP) gelation influenced by konjac glucomannan (KG) addition were studied. The KG addition significantly improved gel strength and water holding capability (WHC) of MP-KG composite gel, but it had additive limitation at 1.0%. The SEM showed that KG (1.0%) reduced the appearance of moisture channels and promoted the formation of an integral MP gel network. Raman spectroscopy showed that KG addition (1.0%) promoted the protein unfolding and the interaction of hydrophobic groups during thermal processing. However, the KG (1.0%) would form continuous viscous hydrogel and interpenetrate with the MP solution, which hindered the interaction of hydrophobic groups during thermal process, and the MP formed a loose and degraded final structure. Hence, MP gels produced with the addition of KG underwent a transformation from a loose structure to a compact structure to an unaggregated structure, which was influenced by moisture stability and phase separation behavior.

The effects of high pressure (100–500 MPa) on chemical forces and water holding capacity of heat-induced myofibrillar protein (MP) gel were investigated. As pressure increased, total sulfhydryl (SH) group content decreased and absolute value of zeta potential increased, which suggested the formation of disulfide bonds and increased the strength of electrostatic repulsion. Surface hydrophobicity and normalized intensity of the 760 cm −1 band showed a maximum value at 200 MPa, indicating that 200 MPa was the optimum pressure for hydrophobic interactions. Hydrogen bonding of MP gel was strengthened at pressures of 300 MPa and above. Bound water (T 2b ) had lower water mobility and was more closely associated with proteins. Free water (T 22 ) had higher water mobility. More free water was attracted by proteins or trapped in gel structure, and transferred to bound or immobilized water as pressure increased. A value of 200 MPa was the optimum pressure for the water holding capacity of MP gel.

In order to investigate the mechanism between flavor binding and proteins degradation during meat processing, the influence of different trypsin contents on the structure of myosin and the adsorption capacity on aldehydes and ketones was determined. The 1% treatment produced subfragment 2 (S2), light meromyosin (LMM) and decreased 18 and 16kDa light chains; 5% and 10% treatments produced 100 and 65kDa new bands and more S2, LMM and cleaned light chains. With the rising trypsin contents, β-sheet, β-turn, random coil, hydrophobicity and total sulfydryl content increased; solubility, α-helix and free percentages of aldehydes and ketones decreased. The increase of absorbing capacity could be attributed to the increased hydrophobicity and total sulphydryl and the unfolding of secondary structures by exposing reactive amino and thiol groups and hydrophobic sites; the decreased solubility was related to the increased hydrophobicity. The trypsin-dose dependent proteolysis of myosin increased the retention of volatile compounds.