Cold Brew Iced Tea

Before you start

Cold brewing extracts tea slowly in refrigerator-cold water. At low temperature, the aromatic and sweet compounds dissolve readily while the bitter catechins and much of the caffeine come out more slowly, so the tea tastes rounder and softer than the same leaves brewed hot. It also never clouds, because it is never heated and chilled.

The method is almost effortless: weigh the leaves, add water, refrigerate and strain. What changes the result is the ratio and the steep time for each tea type. Green teas get grassy and flat if left too long; black teas need the full night to build body. Because cold water extracts less, use a little more leaf than you would for hot tea.

Ingredients

• 10 to 12 g (about 4 to 5 tsp loose, or 5 bags) loose-leaf tea — black, oolong or green; whole leaves give the cleanest result
• 1 liter (4 cups) cold filtered water
• to taste simple syrup (1:1) — optional, about 15 ml per glass
• 1 per glass lemon wedge or orange slice — optional
• as needed ice cubes

Method

1. Weigh the tea. Start with 10 g per liter for black or oolong and 8 to 10 g for green tea. Delicate whites and Darjeelings can go up to 12 g.
2. Put the leaves in the jar and pour in the cold filtered water. Swirl so all the leaves are wet; dry leaves floating on top extract unevenly.
3. Cover and refrigerate. Steep green tea for 6 to 8 hours, oolong 8 to 10 hours and black tea 10 to 12 hours.
4. Taste a spoonful at the minimum time. It should taste full and smooth; if it is still thin, give it another 2 hours.
5. Strain through a fine-mesh strainer into a clean jar. Do not press the wet leaves, which pushes out fine sediment and a little bitterness.
6. Serve over ice, sweetened if you like, with citrus on the side. Keep the strained tea in the fridge.

Tips for success

• Water quality shows clearly in cold brew because nothing masks it. Filtered or spring water makes a sweeter, cleaner tea.
• Japanese sencha and Taiwanese high-mountain oolong are especially good cold brewed; they turn sweet and floral with almost no astringency.
• Strain on time. Leaving green tea in the water overnight past 10 hours gives a vegetal, slightly stale taste.
• Cold brew is milder in caffeine per glass than hot tea from the same leaf, but it is not decaf.

Substitutions

Loose-leaf tea

Tea bags work. Fannings in bags extract faster, so check at the shorter end of the time range and use 5 bags per liter.

Simple syrup

Honey syrup (equal parts honey and warm water, cooled) adds floral sweetness. Granulated sugar will not dissolve well in cold tea.

Cold water

Sparkling water can be used to stretch a stronger cold brew. Make it at 20 g per liter, then dilute 1:1 with chilled soda water just before serving.

Variations

Cold brew peach oolong

Add 2 sliced ripe peaches to the jar with oolong leaves and strain both out together after 8 hours.

Cold brew jasmine

Use 10 g jasmine green tea and steep 6 hours. Excellent with a splash of lychee syrup.

Troubleshooting

The tea tastes weak and watery

Use more leaf, not more time. Raise the dose by 2 g per liter; overlong steeps make tea dull rather than stronger.

It tastes grassy or like cooked vegetables

Green tea steeped too long. Strain at 6 to 8 hours and try a sweeter-style green such as a Japanese sencha.

There is fine sediment in the glass

Broken leaves or tea dust passed the strainer. Line the strainer with a paper coffee filter, or let the tea settle and pour off the top.

Storage

Keep strained cold brew tea covered in the refrigerator and drink it within 3 days for the best flavor. Discard it if it turns sour, stringy or cloudy in a way that does not settle. Do not leave the leaves in the water longer than the stated times.

Safety notes

Cold-brewed tea still contains caffeine. Steeping at fridge temperature, rather than leaving the jar at room temperature, keeps unheated tea out of the range where bacteria grow quickly.