Research on functional properties of hemp seed protein components in different extraction pH

Alkali extraction-acid precipitation method was used to determine the protein isoelectric point of hemp seed meal under the different extraction pH.The results showed that the isoelectric points were 3.5,4.0,5.0and 5.5,with the corresponding extraction pH 8.5,9.5,11.0,11.5,respectively.The protein yield was low with the extraction pH 8.5,while the protein was yellow-brown and smelly with the extraction pH 11.5.The protein solubility,waterholding capacity,foaming ability and foam stability were researched,and found that the protein solubility of extraction pH in 9.5and 11.0were good,and water-holding capacity for four pH condition had a little difference.Because of the different solubility,with environmental pH closer to the isoelectric point,the foamability was worse.While,the foam stability was better,this may be for the repelling force among protein molecules.