Abstract:The function and structure of Pleurotus eryngii protein under different dry heat treatments temperatures were studied.The isolated proteinsamples were exposed to the air at 65，80，95，110℃and 125℃，respectively，for 30 min.Cracks and small pores were observed on the surface of the treated protein under an electron microscope.The total sulfhydryl groups and free sulfhydryl groups in the dry heated protein reduced（p＜0.05）compared with those of the no dry heat protein.The solubility of the protein was improved after dry heat treatment.With the increase in temperature，the foaming ability of the protein increased andpeaked at 95℃，while the treated protein was less stable than the untreated protein.Circular dichroism spectra and UV spectra showed changes in the secondary and tertiary structures of P.eryngii protein.The secondary structure was increasingly disrupted with the increase in temperature，while the tertiary structure of the protein treated at 110℃ and 125℃showcased lower absorbance than that of the untreated protein，which might be because the increased temperature made the unfolded small molecules aggregate to form large molecules.Overall，dry heat treatment changed the structure of P.eryngii protein，and the protein heated at 95℃ for 30 min demonstrated the best functional properties.