Long-term storage of green tea lessens health benefits

Mar 20 2009

Green tea leaves produce antioxidant organic compounds called catechins that reportedly have beneficial health effects, such as fighting bacteria, viruses and cancer.

But consumers need to be aware of possible adverse consequences of long-term storage of commercial tea brands, according to researchers Mendel Friedman and Carol Levin in an article in the Journal of Food Science, published by the Institute of Food Technologists. The study was sponsored by the U.S. Department of Agriculture (USDA) Western Regional Research Center in Albany, California, and Uiduk University in Korea.

Because tea generally does not spoil, it can be stored for extended periods. However, catechins in commercial tea leaves may not remain stable during long-term storage in the solid state.

For the study, tea bags were stored in their original containers in the dark at room temperature for time periods ranging from one week to six months. "Degradation of catechins in commercial tea leaves during a storage time of six months in warehouses, stores or even the home could adversely impact tea's potential health benefits," say the researchers. Even in the absence of moisture, the quality of teas may degrade with time. The researchers added that different tea varieties are harvested in different ways and at different times of the year, which might affect their catechin content.

Read more about the study: http://www3.interscience.wiley.com/cgi-bin/fulltext/121589670/PDFSTART

About IFT
Founded in 1939, the Institute of Food Technologists is a nonprofit scientific society with more than 20,000 individual members working in food science, food technology, and related professions in industry, academia, and government. IFT serves as a conduit for multidisciplinary science thought leadership, championing the use of sound science through knowledge sharing, education, and advocacy. For more on IFT, visit http://www.ift.org.