Cold brewing tea

Cold brewing is a gentle extraction method that relies on time rather than heat to draw flavour from tea leaves. By steeping loose leaf in chilled water over several hours, you extract fewer bitter tannins and less caffeine while preserving delicate aromatic notes. It requires no special equipment beyond a clean bottle or jug, making it an accessible and reliable way to prepare iced tea at home without bitterness.

The mechanics of cold extraction

Hot water dissolves catechins and tannins very quickly, which can introduce harsh bitterness and astringency if not timed with precision. Cold water extracts these bitter compounds much more slowly while still dissolving amino acids, natural sugars, and volatile aromatic oils. As a consequence, cold-brewed tea tastes inherently sweeter, rounder, and noticeably smoother than hot tea poured over ice. The absence of thermal breakdown also helps delicate green, white, and floral teas retain their crisp botanical character.

Leaf ratios and steeping times

A dependable baseline for cold brewing is around 10 to 12 grams of loose leaf tea per litre of cold, filtered water. If you prefer a stronger base to dilute over ice cubes, you can increase this to around 15 grams per litre. Once combined in a clean container, place the vessel directly into the refrigerator. Delicate white and green teas typically require around 4 to 8 hours to infuse, whereas dense oolongs, dark teas, and hearty black teas benefit from 8 to 12 hours of cold extraction.

Best tea types for cold brewing

Almost all tea types perform well in cold water, but some shine exceptionally bright. Japanese green teas like sencha and gyokuro yield intensely savoury, umami-rich liquors with vivid green colour. Rolled green oolongs, such as Tieguanyin, offer crisp floral notes and a clean, refreshing body. White teas bring subtle melon and honey sweetness, while whole-leaf black teas produce a bright, fruit-forward liquor free from the cloudy sediment that often appears when hot-brewed black tea cools down.

Equipment and preparation steps

You do not need specialised apparatus to cold brew tea. A simple glass bottle, a wide-mouthed mason jar, or a pitcher with an integrated strainer lid works perfectly. Simply measure your dry leaves into the container, pour cold water over them, cover tightly to keep out fridge odours, and chill. Once the steeping duration has elapsed, strain out the wet leaves using a fine sieve. Straining promptly prevents over-extraction and keeps the liquid fresh for several days.

Storage and food safety

Because cold brew bypasses boiling water, clean utensils and pure water are important. Always use fresh, potable water and thoroughly washed containers. Keep the steeping tea inside the refrigerator rather than on the kitchen counter at ambient room temperature to inhibit bacterial growth. Once strained, store the cold-brewed tea in a sealed glass bottle in the fridge. For optimum flavour and freshness, consume the tea within three to four days of straining.

Key points

Use around 10 to 12 grams of loose leaf per litre of cold filtered water.
Steep green and white teas for 4 to 8 hours, and oolongs or blacks for 8 to 12 hours.
Keep the tea inside the refrigerator while steeping to ensure freshness and safety.
Strain out the leaves once brewed and consume within three to four days.