The same tea tastes different from last time

In short

Tea is an agricultural product sold under a stable name, so a real change and an imagined one feel identical. Work through what changed on your side first, because it is usually one of four things and all of them are easy to check.

Likely causes, in order

Most likely first. Answer the question under each one before moving on — several of these look alike in the cup and are told apart only by what was done to the leaf.

1. 1. A new harvest of the same tea

   Leaf quality

   Check: Is there a harvest year or season on the packet, and does it differ from the last one?

   Fix: Named teas are re-made every year from a new crop. Year-to-year variation is real and expected, and it is largest in flush-based regions such as Darjeeling and in weather-sensitive districts such as Uva.

2. 2. The tea has rested or faded since you bought it

   Storage

   Check: How long has the packet been open, and how is it stored?

   Fix: Roasted oolong genuinely improves over the first months as the roast settles; green tea genuinely declines. Both are the same tea changing in storage rather than a different tea.

3. 3. Your water changed

   Water chemistry

   Check: Have you moved, changed filter cartridge, or started using bottled water?

   Fix: Water is the largest single ingredient and the one people never think to control. Brew the same leaf side by side with filtered and unfiltered water before blaming the tea.

4. 4. A parameter drifted without you noticing

   Technique

   Check: Are you still weighing, or has the dose become a spoonful? Is the kettle on the same setting?

   Fix: Habits drift. Re-weigh, re-time and re-check the temperature once; the deviation is usually larger than expected.

5. 5. A blend was reformulated

   Leaf quality

   Check: Is it a named blend rather than a single origin?

   Fix: Blends are built to a flavour target from whatever the market supplies, so their components change continuously by design. A blend tasting different is the blender working, not failing.

Related problems

Sharing a cause category, a tea type or a brewing method with this one.

• I bought a big bag to save money and it was stale before I finished it — A large quantity bought at a good unit price faded well before it was drunk, so the saving turned into waste.
• I cannot taste the difference between my expensive tea and my cheap one — Two teas at very different prices taste much the same in the cup, and the tasting notes on both packets describe things you cannot find.
• I have too many teas open and most of them are going stale — A dozen or more packets are open at once, three or four get drunk regularly, and the rest fade quietly on the shelf until they are thrown away.
• I think the famous tea I bought is not what it claims to be — A tea sold under a protected or famous place name — West Lake Longjing, Tongmu Zheng Shan Xiao Zhong, a named pu-erh village, Anxi Tie Guan Yin — does not match its descriptions, and the price was suspiciously reasonable.
• My green tea tastes flat and looks dark in this house — A delicate green tea that tasted bright elsewhere comes out dull and heavy here, with a darker, browner liquor than it should have and none of its aroma.

Sources