Tea leaves will undergo changes over time, regardless of whether they are vacuum-packed. The chlorophyll and polyphenol compounds in the tea can cause the leaves to age and turn yellow or red. If the tea was not sufficiently dehydrated or dried improperly, the Infusion may become bitter and astringent. If stored improperly, it may even develop mold. Therefore, when you return to Drinking Tea that has been opened for some time, there are certain issues to be mindful of.
First, check if the tea has developed mold. Place the tea leaves in your hand and examine them under bright light or give them a light sniff. If there is a musty smell, the tea should not be consumed and can instead be used as plant fertilizer.
Brewing Method to Address the Issue
If the dry tea leaves have a grassy scent or other off-flavors, you can seek the assistance of a professional tea roaster or a tea shop to process them. If there is only a slight aged or stale flavor, you can use a brewing method to address this.
Method One
The water temperature should be high, ideally boiling. Allow the first Steeping to sit for longer than usual, then discard the infusion. For subsequent steepings, reduce the time by about half compared to normal, and brew quickly. Drink the tea while it's still hot whenever possible.
Method Two
Decrease the water temperature by a few degrees and follow the normal brewing time. This can help avoid the bitterness and astringency in the tea.
Method Three
It's best to switch to brewing with a larger teapot, such as a teapot warmer, and reduce the proportion of tea leaves. This can improve the taste.
When you find that your tea at home has been stored for too long, check for any signs of mold. If there are some off-flavors due to prolonged storage, you can follow these three methods to brew the tea and still achieve its previous flavor.