Last weekend we spring-cleaned the kitchen (we are late for 2013 spring cleaning not early for 2014!). In the process, I found some very old matcha, which makes for an interesting comparison with the fresh matcha that I bought last week.
Here are the photos. You can see that the fresh matcha is striking bright green but the old one is a dull, grey-green. Tea doesn’t spoil with time but it does loose its flavour and colour especially if exposed to air. Matcha is one of the brisker tea on the fading process. Ideally it should be used within a few weeks of opening but keeping it in an airtight container in the fridge can extend this a little. I’m ashamed to say that the old matcha was not in an airtight container, not in the fridge and has probably been on the shelf for well over a year. In other words, a perfect storm of matcha degradation!
The old matcha still has a strong vegetal aroma but it doesn’t form the nice froth and the taste is unpleasant and slightly sour.
Not all the examples of stale tea are as obvious as matcha and of course it varies with vacuum sealing, conditions etc. but here are the general rules that I use: greens: within 4/5 months (of the harvest date), light oolongs and early Darjeeling: within 6/7 months, black tea (apart from Darjeeling) within 12-18 months, pu-ehr and heavily roasted oolongs: whenever they’re ready – both improve with age.
For the teas that don’t age, I have a terrible habit of not drinking them quickly enough. When I find a tea that I love, I sometimes wait until I can make enough time to really enjoy it, or the right occasion, or someone to share it with. Some fine teas have been lost in this way and the matcha was a good reminder. From now on, I am going to be dedicated in keeping my tea list updated with the date of purchase/harvest. That might sound nerdy but it’s nothing compared to the plans I have for rules in excel and automatic colour coding depending on the best time to drink ;-).