Storing Crude Tea in a Daikai-bag Using Nitrogen Gas

• Published in: Chagyo Kenkyu Hokoku (Tea Research Journal) Vol. 2008; no. 105; pp. 105_35 - 105_41
• Main Authors: Nishimura, Shinichi, Imada, Takahiro, Shinsho, Seiji, Iriki, Hiroyuki, Asai, Junya, Sato, Shoichi
• Format: Journal Article
• Language: Japanese
• Published: Japanese Society of Tea Science and Technology 2008
• Subjects: crude tea; daikai-bag; nitrogen gas; storage
• ISSN: 0366-6190; 1883-941X
• DOI: 10.5979/cha.2008.105_35

We developed a simple and low-cost storage method for keeping crude tea in a daikai-bag. (1) Oxygen in the daikai-bag could be replaced with nitrogen by allowing a continuous flow of nitrogen gas into the airtight container that fed the daikai-bag. (2) When the nitrogen gas mass flow per hour into the container was the same as the volume of a container and the pressure in the container was 0.01 MPa or more, the oxygen concentration in the daikai-bag became 1% or less within 10 hours. Moreover, since there was pressure, mixing with the open air was suppressed. (3) The oxygen concentration in the daikai-bag kept 1% or less for six months by maintaining pressure in the container. (4) The quality of crude tea after six months storage by the new storing method was changed very little compared with tea stored using the conventional storing method which put tea in the aluminum bag and was filled up with nitrogen gas.