Abstract: The crude tea protein extracted and preliminarily purified from the depolyphenoled tea leaves dregs was hydrolyzed by chemical and enzymatic method respectively. These modification methods could obviously improve the functional proper- ties of tea dregs protein, such as solubility, water absorption, foaming capacity, emulsibility and gelation; but slightly reduce the oil absorbability. The functional properties of modified tea dregs protein could compare favourably with soybeen protein concentrate (SPC). The degree of hydrolysis could influence these functional properties differently. It was also confirmed that in the AP-TEMED system assay the 0.1 mg/L tea crude protein could eliminate the peroxide free radicals with the efficiency of 52.0%.

Key words: tea protein, modification, functional properties, eliminate peroxide free radicals