The above summary disregards the changes in caffeine level (albeit smaller than genetic, edaphic and climatic mediated changes) produced during tea processing."
The interview link is http://chadao.blogspot.com/2008/02/caffeine-and-tea-myth-and-reality.html if you'd like to read the entire posting..worth it!
He also debunks the 'steeping one time first before infusing for beverage purpose to remove significant caffeine' theory.
He then links more information on the caffeine question: http://nobleharbor.com/tea/caffiene.html [sic] 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.' A good rule of thumb is that tea, in general, has 1/3 to 1/2 the caffine of coffee when both are brewed. As Mr. Melican has so eloquently pointed out, the amount of caffeine in tea is dependent not just on the level of oxidation.
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 at all to the wonderful assortment of herbals we also carry.
Diane Walden is co-founder of two retail loose leaf companies. She and her husband own and manage California Tea & Coffee Brewery in the Winchester Meadows Plaza in Temecula. The shop is one of the best rated tea stores in the U.S. according to TeaMap.
Website: http://www.caltcb.com.
Diane can be reached at 951-693-5727 with any questions on teas & herbals.
All photos in this column courtesy of Regina Fell Designs http://www.reginafell.com/