Researchers have declared that long storage of commercial green tes brands may reduce the concotion's health benefits, which include fighting bacteria, viruses and cancer.
The healthy tea's leaves produce antioxidant organic compounds called catechins that reportedly have beneficial health effects. But consumers need to be aware of possible adverse consequences of their long-term storage, say researchers Mendel Friedman and Carol Levin in an article in the Journal of Food Science, published by the Institute of Food Technologists.
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.