The Rise of Cold Brew Tea
Cold brew has become incredibly popular in recent years, especially among people looking for a refreshing drink that highlights the natural flavor of tea. Before this trend, iced beverages were already well-loved: from iced lemon tea to bubble tea, many of us grew up drinking sweetened tea-based drinks. I still remember that when I was little, the first big hit was lemon iced tea—delicious, but extremely sweet.
As demand grew, large beverage companies began producing simple jasmine iced tea, oolong iced tea, and even “pure” iced tea. Yet even in the simplest formulas, they still added some sugar or artificial sweeteners.
When producers realized the growing market for pure infusion teas, people were skeptical. I remember very clearly how a truly pure infusion tea—unsweetened, simple, clean—was mocked by people around me for being “boring.” And yet, look at how popular it has become now. As we grow older, our tastes shift: we start to appreciate simplicity, natural beauty, and authenticity. And of course, we begin paying more attention to how much sugar we consume every day.
Fruits and tea infusions are still a wonderful combination—I enjoy them a lot too. But sometimes, you just want a simple cold brew iced tea that lets you taste the tea itself—the natural sweetness that comes from the leaves. This is especially true for roasted or heavily baked teas: when brewed cold, their inherent sweetness becomes even more pronounced.
A Bit of History: How Cold Brew Tea Developed
Cold brewing tea originated in Japan, where it is known as mizudashi (水出し). The technique was created to produce a smooth, low-bitterness tea by steeping high-quality leaves in cold water for several hours. Because cold water extracts fewer tannins, the resulting tea tastes sweeter, softer, and cleaner.
Later, Taiwan embraced this method and elevated it, especially with high-mountain oolongs. Many fine dining restaurants in Taiwan began serving pure oolong cold brew—no sugar, no additives—because cold brewing brings out the floral notes, natural sweetness, and elegant aftertaste of premium teas. This helped the trend expand quickly across Asia and eventually to the rest of the world.
Today, cold brew tea has become a symbol of minimalism, health, and authenticity—a way to appreciate tea at its purest.
How to Make Cold Brew Tea
Cold brewing is simple and requires no special skills.
Standard Cold Brew Method (Recommended)
Ingredients
- 5–10 grams of tea (this varies depending on the tea; dosage recommendations are indicated on each tea’s page)
- 1 liter of cold or room-temperature water
- A clean bottle or jar
Steps
- Add the tea leaves to the bottle.
- Pour water over the tea.
- Close the container and refrigerate for 5–12 hours.
(Lighter teas need less time; darker or roasted teas may need longer.) - Strain before drinking.
- Enjoy within 2–3 days for the best flavor.
Cold brewing extracts flavors slowly, creating a smoother, sweeter tea without any bitterness.
Japanese Traditional “Ice Brewing” (氷出し / Kōridashi)
What Is Ice Brewing (Kōridashi)?
Kōridashi (氷出し) literally means “ice‑extracted”: you place ice cubes on top of tea leaves, and as the ice melts, the water slowly infuses through the leaves. It’s a very gentle, low-temperature brew — because the water that does the extraction comes from melting ice (around 0 °C), the extraction is extremely gradual. This method is particularly praised for high-quality Japanese teas (like gyokuro, shaded sencha, or first-flush green teas) because it emphasizes umami and sweetness while minimizing bitterness and astringency.
How to Make Kōridashi (Ice-Brewed Tea)
Here is a practical guide to doing ice brewing:
Ingredients / Equipment
- High-quality loose-leaf tea.
- Ice cubes — preferably made from clean, filtered water
- A teapot or steeping vessel
Steps
- Add tea leaves to your teapot. For example, the Global Japanese Tea Association suggests using “a larger quantity of leaves than usual” for kōridashi.
- Place the ice cubes directly on top of the tea leaves.
- Wait patiently for the ice to melt completely. Depending on conditions (room temperature, ice size, vessel), this can take several hours.
- Once the ice has melted, strain the tea to separate the leaves, and serve the resulting brew.
Cold Brew, Kōridashi, and Hot Iced Tea: What’s the Difference?
All three methods give you cold tea, but the way they extract flavor makes a big difference.
Classic Cold Brew
- How it works: Tea leaves steep slowly in cold or room-temperature water for several hours.
- Flavor profile: Smooth, naturally sweet, gentle, with very little bitterness.
- Why it tastes this way: Cold water extracts fewer polyphenols and tannins—the compounds that cause bitterness and astringency—while amino acids like theanine dissolve more readily at lower temperatures, producing a smooth, naturally sweet flavor, and caffeine is released more slowly, making the tea gentle and less stimulating..
Japanese Ice Brewing (Kōridashi / 氷出し)
- How it works: Ice cubes slowly melt over the tea leaves, letting nearly freezing water do the extraction.
- Flavor: Sweet, rich in umami, silky, with almost no astringency.
- Why it tastes this way: The extremely low temperature pulls out amino acids without releasing much bitterness or caffeine.
Hot-Brewed Then Cooled
- How it works: Brew tea hot, then let it cool or pour over ice.
- Flavor: Stronger aroma, fuller body, but often bitter and astringent.
- Why it tastes this way: Hot water extracts everything quickly — tannins, caffeine, and other compounds that remain bitter even after cooling.
- Best for: Strong black teas, fruity blends, or when you want a quick, robust iced tea.
What Types of Tea Are Best for Cold Brew?
Different teas develop unique personalities when cold brewed.
◎ Oolong Tea (Excellent Choice)
- High-mountain oolong
- Lightly roasted oolong
- Roasted oolong (Da Hong Pao, Tieguanyin)
Cold brewing highlights floral aromas and natural sweetness. Taiwan is especially famous for this style.
◎ Green Tea
- Japanese sencha
- Chinese longjing
Freshness is key—use good-quality leaves to avoid bitterness.
◎ White Tea
- Bai Mu Dan
- Shou Mei
White tea becomes incredibly sweet, soft, and refreshing when cold brewed.
◎ Black Tea
- Assam
- Ceylon
- Taiwanese Ruby Black Tea
Cold brew smooths out bitterness and brings out round, aromatic flavors.
◎ Herbal Tea
- Hibiscus
- Mint
- Chrysanthemum
Perfect for caffeine-free options and naturally fragrant.
Why Cold Brew Tea Is So Appealing
- No bitterness thanks to slow extraction
- Naturally sweet without sugar
- Healthier and hydrating
- Showcases the original flavor of the tea
- Easy to prepare—just steep and chill