I have only been covering the specialty tea business for a year and a half, and I’ve already seen or heard the subject of the so-called “30-Second Decaffeination” method come up many times. The last T Ching post on the topic generated quite a bit of heated discussion.
The method is usually described something like this: Put caffeinated tea in a cup, pour boiling water over it, wait 30 seconds, discard the water, and keep the now-decaffeinated leaves for steeping at their normal temperature and time. After this 30-second bath in boiling water, proponents of the method say the tea loses “most” of its caffeine (amounts given range from half to “nearly all”).
There are many such proponents – some of note. Most recently, Atlanta Tea Examiner Althea DeBrule posted a YouTube video of Bigelow Teas President Cindi Bigelow showing viewers “how to naturally decaffeinate your favorite tea”.
At the same time, many other people – also, some of note – insist the 30-second decaffeination method is actually the 30-second decaffeination myth. Most recently, QTrade Teas & Herbs CEO Manik Jayakumar told me that the whole idea was “nonsense”. It has been well-proven, he added, that you cannot decaffeinate tea simply by pouring boiling water over it.
Being a journalist, I decided to find the facts for myself.
Some 30-second decaffeination debunkers like to point to a 13-year-old study done at Auburn University in Auburn, Alabama. I got my hands on it and even spoke to one of the original researchers, Professor Leonard Bell.
The study is titled “Tea preparation and its influence on methylxanthine concentration”. Having noticed that the Chinese would always discard the liquor of their first tea infusion (with the idea that they were getting rid of some unwanted components), the researchers set out to determine the amounts of methylxanthines (caffeine, theobromine, and theophylline) left in the liquor after each of three infusions.
Although it’s interesting, this study doesn’t prove that tea can or can’t be decaffeinated in 30 seconds for one simple reason: None of the tea studied was steeped for 30 seconds; each infusion was done for five minutes.
That said, Bell et al. did find that after the first (five-minute) infusion, 69 percent of the caffeine was released, on average, across the different types of tea (black, oolong, and green). Another 23 percent of caffeine was released on average after the second infusion, and 8 percent after the third.
The better study to look to was one done by research lab ChromaDex, whose president and CEO Frank Jaksch presented the results at the 2008 World Tea Expo in Las Vegas.
In part of the presentation, Jaksch addressed common tea myths, including the 30-second decaffeination method. In answer to the question, “Does a 30-second hot water wash remove most of the caffeine? (Industry believes this to be 80 to 85 percent removal),” Jaksch said, “No.”
In ChromaDex’s study of green tea “washing,” tea brewed for five minutes without a wash was 2.9 percent caffeine, based on the dry weight of the leaves. Tea brewed for five minutes after a 30-second wash was 1.9 percent caffeine, based on the dry weight of the leaves. In other words, the 30-second wash produced a liquor with 34 percent less total caffeine content than liquor with no wash, suggesting that just over one-third of the caffeine was removed by the 30-second wash.
So, as with many things, the true answer to the question appears to be somewhere in the middle. Does a 30-second rinse decaffeinate your tea? Yes…but only partially. A subsequent five-minute infusion will remove much more of the caffeine, and a third infusion, nearly all.
Of course, none of this addresses the issue of flavor. Do you really want to drink a green tea that’s been brewed in boiling water for five minutes? And none of the studies or articles I found were comprehensive in terms of looking at varying types of tea and brewing methods across the board. Instead, they examined the results obtained with one consistent tea and/or method.
Until a more comprehensive study emerges, the safest route may be to stick to conventional wisdom: If you want a good-tasting, completely caffeine-free tea, go with an herbal.