Patent ID: 7981449

Claim:
A process for producing a purified product of green tea extract, which comprises: a primary step comprising: subjecting an aqueous solution of green tea extract to solid-liquid separation by filtration using a membrane having a pore size ranging from 1 to 30 μm and/or centrifugal separation to obtain another aqueous solution of green tea extract, controlling a turbidity of said another aqueous solution to a range of from 0.2 to 2.0 as measured with a concentration of non-polymer catechins therein adjusted to 1 wt %, and a second step comprising: allowing said another aqueous solution of green tea extract to pass through a spiral polymer membrane or a hollow fiber polymer membrane having a membrane pore size of from 0.05 to 0.8 μm such that said turbidity of said another aqueous solution of green tea extract is reduced to lower than 0.2 as measured with a concentration of non-polymer catechins therein adjusted to 1 wt %, wherein said polymer membrane is selected from a polymer hydrocarbon membrane or polymer fluorocarbon membrane.