Cold brew sure hit the spot on a warm spring day in Atlanta last week where coffee enthusiasts extolled its virtues and throngs among the 12,000 attending sampled offerings at the annual convention of the Specialty Coffee Association of America.
Cold brew coffee is hot. When Peet’s Coffee & Tea switched its iced coffee for cold brew in 2014 and sales increased 70%. Starbucks soon followed. Consumption of ready-to-drink coffee is up 52% since 2009 accounting for 24% of coffee sales in 2013.
During the Re:Co Symposium a group of experts including Diane Aylsworth, vice president of cold brew at Stumptown Coffee Roasters and Julia Leach with Toddy, the firm that popularized cold brew beginning in 1964, set to rest the notion that cold brew and its hip nitro cousin is a craze. The category is resilient with a broad base of support and resembles in many ways the craft brew movement, said Michael Kiser, founder of Good Beer Hunting, a consultancy working with World Barista Champion Stephen Morrissey to bring craft beer and specialty coffee culture and customers together.
Little wonder then cold brew tea would seek the limelight.
Several tea companies have introduced tea brewed for 10 to 14 hours in cool to lukewarm water. The tea is then chilled before it is served. These are not concentrates diluted to make iced tea, the current trend is high quality artisan loose leaf teas. Some rely on green tea cultivars that extract nicely at low temperatures. TWIG Cold Brew Teas bottles Bōcha, a type of Japanese roasted green tea made using the twigs and stalks of the tea plant, rather than the leaves. The tea is grown in Shiga Prefecture, Japan. The brand also offers a bottled cold brew Keemum from Qimen, in China’s Anhui province and a Formosa Oolong from Northern Hsinchu in Taiwan.
The Tea Spot, TeaSource, Samovar Tea Lounge and Arbor Teas all offer online recipes for brewing tea and even Lipton has a cold brew tea bag.
“Cold brewing tea and coffee are all the rage, and for good reason: they’re idiot-proof,” writes Karen Ahn on the WonderHowTo website. “So the beauty of cold-brewed tea and coffee is manifold: because the tea leaves or grounds are left in cold water overnight, your brew has a smooth lusciousness with no risk of that tannic, puckery effect you get from brewing green and oolong teas for too long, while it lacks the harsh astringency that poorly made coffee contains. Plus it’s healthier in a couple of key ways,” she writes.
Fresh brewed green tea whether cold or hot contains the same percentage of antioxidants. A 2012 study at Taiwan’s National Chung Hsing University showed that cold-brewed green tea steeped 12 hours had the same high level of polyphenols at tea steeped in hot water for five minutes.
In 2014 Fresh Cup Magazine interviewed The Tea Spot founder Maria Uspenksi on her discovery that after a night in the Mason jar “I’d have two or three amazing bottles of fresh tea. And I was shocked, because some of them tasted better than they did hot-brewed.”
“In a hot brew, the water molecules hit the leaves like wrecking balls, plowing away big and small molecules, and fast. Here in the cold brew, it’s more like an archeological excavation, slow brushwork that only pulls off highly soluble compounds,” writes Fresh Cup’s Cory Eldridge.
“The carbohydrates in the tea leaf dissolve readily into water whether it is hot or cold,” explains Donna Fellman, online education director of the World Tea Academy. The water pries off some simple amino acids as well but what does not come off are compounds that add the deep and sometimes harsh flavors in hot tea. Polyphenols, for instance, cause astringency in tea, not a taste but that dry sensation you sometimes get. Caffeine is pure bitterness. Those classes of compounds do show up in cold-brewed tea, but at tiny fractions of their hot-brew numbers.