At the California Tea and Coffee Brewery, we hear “need caffeine / want black tea” regularly. Many people have been told that black tea has more caffeine by another tea place or a coffee and tea place, or just thought it worked that way. The conclusion that many have drawn is that the darker the tea – or the stronger the taste – the more caffeine. Of course, that’s a misconception for both tea and coffee, and the controversy about which tea has the most caffeine has been going on for quite awhile.
We have a short summary on our counter for anyone who would like to read it, based on various studies. However, I came across an article the other day on the great blog Cha Dao with Nigel Melican that was so thorough, I thought it would be great to share parts of it.
The first passage that stood out for me was the following:
“Three scientifically verifiable facts are:
- Caffeine level varies naturally in types of tea and levels in one type may overlap with another type
- Black and green tea manufactured from leaf from the same bushes on the same day will have virtually the same caffeine levels (within +/- 0.3%)
- For a given bush, the finer the plucking standard, the higher the caffeine level …
The above summary disregards the changes in caffeine level (albeit smaller than genetic, edaphic and climatic mediated changes) produced during tea processing.”
Mr. Melican goes into much more detail, including discussing the effects of withering and oxidation on the leaves and amount of caffeine. He also debunks the quick-decaf process that was so popular on the Internet awhile back as follows:
“Again we would have to be washing our tea for a long period – three to four minutes to achieve 80% decaffeination. While a 30-second ‘wash’ under Spiro’s rather extreme laboratory conditions (small leaf CTC tea, loose in the ‘pot’ rather than in a teabag, at constant temperature and stirred vigorously) leached 20% of caffeine rather than the 9% yielded by Hicks’s more normal steeping, neither of these scientifically conducted findings comes anywhere near the 30-second/ 80%-decaffeination claims perpetuated as an Internet Myth.”
Finally, Mr. Melican provides links to informational sites that serve to make us (or me) even more unsure of what to tell customers to feel 100% accurate:
This page supports the information given above – summarizes the Hicks et al paper, and in places borrows some of my own data, with a few (unimportant) errors. It debunks some of the popular caffeine myths and concludes ‘all teas have roughly similar caffeine contents, and one cannot rely on the belief that green tea has less caffeine, as asserted by many popular claims.’
The Linus Pauling Institute gives a fairly inconclusive comment on the level of caffeine in tea showing data (from just 20 snapshot analyses) that the green teas they analyzed varied from 40 to 211 mg/liter, while the black teas varied from 177 to 303 mg/liter — a larger and more representative sample of the worlds [sic] teas could have would have [sic] increased these ranges and the overlap considerably. However, LPI do suggest that the popular belief of low caffeine level in White Tea is misplaced: ‘Buds and young tea leaves have been found to contain higher levels of caffeine than older leaves, suggesting that the caffeine content of some white teas may be slightly higher than that of green teas.'”
I’m thankful that “tea scientists” with the status of Nigel Melican have taken the time to talk about the subject of caffeine in tea. Whatever our beliefs, there is definitely caffeine in tea, and since we don’t carry any decaf teas, we kindly point those who don’t want any caffeine at all to the wonderful assortment of herbals we also carry.