Does tea go bad?

Tea, whether loose-leaf, or in tea bags, loses its flavor slowly over time, and in some rare cases, can spoil or develop "off" qualities in the aroma or flavor. The rate at which this happens depends on how the tea is stored, and what variety it is. Many tea retailers overstate the degree to which tea loses its flavor, because they have an interest in continually selling their product. Most stale tea becomes somewhat bland but is still perfectly drinkable.

The aroma chemicals in tea are volatile and will escape into the air if the tea is not stored in an airtight container. For most teas, then, it is best to store the tea in an airtight container. The tea must be completely dry, or else it can mold, causing the tea to spoil.

Tea should also be stored away from light. The best way to accomplish this is to store the tea in metal tins. If you store your tea in glass jars or other containers that let light through, keep them in a closed cupboard.

One exception to these recommendations are aged teas or teas that you plan on aging. These include Pu-erh tea, and a few other types of tea. These teas are generally stored in a porous container, like a ceramic jar, in a dark, dry area away from other smells or aromas. They have active bacterial and mold cultures that enhance the quality of the tea if it is stored properly.