The Tea Lover's Way to Make the Best Cold-Brew Iced Tea

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Photographs: Vicky Wasik

Summer can be tricky season for a tea lover. At a time when tea shops everywhere are hawking their freshly picked spring harvests, it's too damn hot to pull out the kettle and brew any of them. (How people swig hot tea all summer in the swampy heat of Hong Kong and Chennai I do not know.) The solution for those of us who can't stand the heat is to brew our tea ice-cold, especially considering how most of the bottled iced tea you can buy in the States—overly sweetened to cover up a jolt of tannins, and rank with off flavors— isn't worth its bottle.

There's more to making quality iced tea than meets the eye. On the surface, you can ice any old tea any way you want and get a refreshing drink, but the way I see it, "refreshing" and "drinkable" are just the starting point. A good iced tea can be just as complex, interesting, and delicious as a hot tea, and we shouldn't have to sacrifice cold temperatures and Collins glasses for the most interesting facets of the teas we love. If coffee nerds can geek out about iced beverages, there's no reason us tea people can't do the same.

The Mark of A+ Iced Tea

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What does a fantastic iced tea taste like? Much of that answer depends on you and your tastebuds, but for me that means a tea that's naturally sweet (sugar need not apply), clean-tasting, and refreshing with little to no bitterness and astringency. Astringent tannins dry out the tongue, leaving you feeling parched even after a big gulp, and while they add structure and balance to hot tea, they're just not what I'm after in a glass of iced.

A really good tea doesn't just taste good; it's aromatic, too, and it also has some body, a rounded richness than lingers long after you've finished a sip, leaving a sweet finish on the tongue and down your throat. I want that quality in my iced tea as well, something to cool me down even once I've drained my glass.

In short: A great iced tea makes you pause and take notice. It's a different animal from hot tea, but done right, is just as worthy of savoring.

On the road to great iced tea, we have three questions to consider: the brewing method, tea leaf concentration, and the teas best suited to the job.

Getting Steeped

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A few years ago, Kenji did a deep dive into sun tea, the practice of brewing tea using the heat of the sun for hours. He effectively punctured the entire concept, finding that a tea you cold-brew in the fridge tastes just as good as sun tea, and a little cleaner in flavor, plus it doesn't carry sun tea's risk of bacterial growth. He also found what many tea drinkers know: if you brew a tea hot, then chill it down in the fridge, you get a drink that tastes like stale cold tea.

I did my own version of that test, comparing a high quality green tea brewed in the fridge with cold water to brewing hot tea, covering it, refrigerating until cold. I also tried a tea version of the Japanese iced coffee method, which many coffee people vastly prefer to cold brew these days, in which I brewed tea at double strength, then diluted it to "normal" strength over ice cubes to ice it. The method's advocates say that, for coffee at least, the resulting brew is cleaner and brighter with less unwanted oxidation.

But tea doesn't play by coffee's rules, at least not in my tests. Hot tea chilled down to iced still tastes like bitter mulch water. The Japanese method fared a little better: it had the body and richness I wanted, but tasted simultaneously over-extracted and watered down. The cold-brew method, steeped overnight for eight hours, worked like a charm—sweet, refreshing, and full of great body and an aftertaste that cooled my throat down like an alpine breeze.

Even better, I've yet to over-steep a tea when cold-brewing. Batches that steep for 24 hours don't taste bitter or even noticeably different to those that steep for five or eight, which makes it especially easy to make a large batch overnight and drink it for hours the next day. Once you're done steeping, don't toss those leaves! You can re-steep them for a second or even third brew that, while not as powerful in flavor and body, still tastes better than most of the bottled stuff. Remember, good tea doesn't come cheap, so it's worth wringing every last drop of flavor out of your purchase.

Dialing in Concentration

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Three batches of cold brew sencha made with different concentrations of leaves. The glass on the left tastes bland and watery, while the one on the right is bitter and over-extracted. The one in the middle is just right.

"When it comes to cold brew, nothing impacts the bitterness of your tea more than how much leaf you use."

Unlike cold brew coffee, good cold brew tea doesn't need much in the way of tea leaves, but just how much still matters. Use too little and your tea will taste bland and watery; use too much and it's overly bitter. When it comes to cold brew, nothing impacts the bitterness of your tea more than how much leaf you use.

After playing around with ratios, I've settled on eight to 12 grams of tea per quart of water. For most teas, that's a rounded tablespoon, though if your leaves are fluffy, curly, and light, you might need a little more. Your mileage may vary depending on the exact tea, but start with a fat tablespoon and a quart of cold water (filtered? bottled? depends on your water source), and steep in a covered glass or plastic container overnight (both materials work fine). Strain off the leaves the next day, but keep them around for another steeping or two.

The Best Teas for Cold Brewed Ice Tea

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Before I get too tea-snobby on the subject, I'll say it again: you can cold brew any tea you want and get something good to drink. And yes, the difference between decent tea and great tea is much smaller with cold brew than hot. But chances are, if you've read this far, you're okay going the extra mile for an amazing sip, and higher quality teas do yield higher quality cold brew. And if you want to dig really deep, some teas take much better to cold brewing than others.

Black tea, the most common tea in the West, is in many ways the worst candidate for serving iced. Its golden-fruitiness gets downplayed by cold temperatures, and oftentimes it's plagued with high levels of tannins that dry out the tongue. I'll drink iced black tea, but it doesn't leave me feeling that refreshed. Those tannins are likely why many iced teas are made deliberately weak, or loaded with sugar to fight back against the astringency.

Instead, consider broadening your tea horizons to other styles. Here are the four that I find myself cold-brewing the most.

White Tea

Delicate and aromatic, white tea leaves bring a lovely perfume to cold brew and a touch of creaminess. The resulting taste is rather light but extremely refreshing. White Darjeeling, silver needle, and white peony all do well here. Tete's Himalayan white, with its exceptional creaminess, has been my recent go-to for white tea cold brew.

Green Tea

Good green tea is all about fresh, clean flavors and aroma, and its grassy backbone takes extremely well to cold brew. It also delivers on body: not viscous per se, but a slippery richness that's especially refreshing down the throat. I've been enjoying lots of beany bilochun this way, but my favorite green cold brew candidate is Japanese sencha. Unlike Chinese-style teas, Japanese greens are steamed to halt the oxidation process, which emphasizes their vegetal notes and brings out complementary hints of pine, melon, and alpine air. Ippodo and O-Cha sell great sencha for cold-brewing.

Roasted Oolong

Green teas are unoxidized; black teas are fully oxidized. Oolongs lie in between—partially oxidized and meticulously processed to draw out unique rounded qualities and powerful fragrances and finishes. Often that processing includes roasting, and if you're looking for a darker iced tea with a crisp, clean bite and notes of honey, flowers, and cream, roasted oolongs are just the thing. For cold brew, I prefer the relatively lighter roasts you'll find in roasted baozhong and roasted high mountain oolongs from Taiwan, but some heavily roasted tieguanyin makes for a buttery, floral indulgence, too. I'd recommend avoiding unroasted "green" or "jade" oolongs for cold brew, though, as they can veer toward astringent.

Mugicha

One of Japan's warm-weather cure-alls, mugicha, a.k.a. roasted barley tea, is the best budget-friendly iced tea option out there. It's not tea, but rather roasted barley, which brews up dark, crisp, and incredibly refreshing, with nutty coffee notes that make it a great iced coffee alternative. It's generally sold in large tea bags, each of which can make a quart of cold brew for about 20 cents. Make this in big pitchers and keep it around all summer long.