Method for the manufacture of caffeine free black tea

US4167589A · kind A · utility

Inventors

• Otto Vitzthum · Bremen, DE
• Peter Hubert · Lemwerder, DE

Key dates

• Filing date: Apr 26, 1977
• Grant date: Sep 11, 1979
• Expiry date: Apr 26, 1997

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A23F3/423
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A caffeine free black tea product is produced by an extraction procedure with a supercritical gas such as carbon dioxide in which first the aromatic content of the tea is extracted with dry gas, then the caffeine content is extracted with wet gas, and finally the decaffeinated tea is reimpregnated with the aromatic content.