Watch out for old, out-of-date tea. Check the tea. Smell it. Look at it and check for dried-out leaves. Taste a piece (but don’t taste it if is has been wet and in a container for a long time, or smells completely different from its original scent; if it smells a sickly sweet [rotted]).

It helps to know how a specific tea will smell before you buy it. If you happen to buy a tea frequently, then you can check at the store if it has gone bad before buying it.

If you are buying loose leaf tea, make sure you examine what you are putting in the pot. Rarely small objects, such as twigs, foil (depending on the wrapping), or insects can make their way into tea accidentally.

(China.org.cn August 8, 2011)