High Pressure Treatment Modifies Rigid Structure of Myoglobin and Improves Its Digestibility

Objectives Myoglobin is a special globular protein composed of a polypeptides chain and a heme group. Our previous in vitro and in vivo studies have shown that myoglobin is less susceptible to digestion because of its rigid structure. High pressure treatment is gaining more and more popularity in meat industry. To improve the digestibility and nutritional value of myoglobin, the effects of high pressure treatment on the structural and nutritional properties of myoglobin were investigated. Methods Myoglobin was treated during 100–400 MPa for 20 min, spectroscopic techniques and an in vitro digestion model were performed. Results High pressure treatment induced unfolding of globin and dissociation of heme, with an increase in the absorbance of Soret band and a reduction in the intensity of intrinsic and synchronous fluorescence spectra. Some certain changes occurred in the dissociated heme group, as the content of heme and metmyoglobin decreased. The gastric and intestinal digestibility of myoglobin increased as the pressure rose. Conclusions The results indicated that high pressure treatment could be a promising technology to improve digestibility of myoglobin by modifying its structure to improve its nutritional value. Funding Sources This work was supported by the grants from NSFC (32072211).