Black Tea: What Makes It Black, Caffeine and How to Brew It

Black tea is the most widely drunk tea in the Western world: malty, brisk and full-bodied, and just as good plain as with milk. This guide explains what makes black tea different from green tea, what gives it its color and flavor, how much caffeine it contains and how to brew loose-leaf black tea well.

Table of Contents

• 1. What makes black tea black
• 2. Black tea vs green tea
• 3. Caffeine and L-theanine
• 4. Whole leaves vs tea bags
• 5. How to brew black tea
• FAQ

1. What makes black tea black

All true tea comes from the Camellia sinensis plant. For black tea, the leaves are withered, rolled and then fully oxidized before drying. Oxidation turns the leaves dark and creates theaflavins and thearubigins, the compounds that give black tea its amber-to-red color, its brisk body and its malty depth.

2. Black tea vs green tea

Green tea is heated soon after picking to stop oxidation, so it stays green, fresh and grassy. Black tea is oxidized fully, so it is darker, stronger and more robust. Black tea also keeps its flavor longer in storage and stands up well to milk and sugar.

• Assam: bold and malty, ideal with milk.
• Darjeeling: lighter and muscatel, best plain.
• Ceylon: bright and citrusy, great iced.
• Keemun: smooth, with cocoa and stone-fruit notes.

Explore black tea and flavored black teas such as Earl Grey and chai.

3. Caffeine and L-theanine

A cup of black tea typically contains about 40 to 70 mg of caffeine, roughly half of a similar cup of brewed coffee. Tea also naturally contains L-theanine, an amino acid found in the tea plant. Many people find a cup of black tea a gentler morning ritual than coffee. See our guide to caffeine levels in tea for details.

4. Whole leaves vs tea bags

Most supermarket tea bags hold small broken pieces (“fannings” or “dust”) that brew quickly but can taste flat or bitter. Whole loose leaves have room to unfurl in the pot, which gives a fuller, more layered flavor and allows several steeps.

5. How to brew black tea

1. Use about 1 teaspoon (2 to 3 grams) of loose leaves per 8 oz cup.
2. Heat water to 95 to 100°C (203 to 212°F).
3. Steep for 3 to 5 minutes: 3 for a lighter cup, 5 for a strong one to take with milk.
4. Strain fully so the leaves do not keep steeping and turn bitter.

Pro Tip: If your tea tastes bitter, shorten the steep before you reduce the amount of leaves.

FAQ

How much caffeine is in black tea?

Usually about 40 to 70 mg per cup, depending on the tea and how long it steeps. That is roughly half of a typical cup of brewed coffee.

Can I add milk to black tea?

Yes. Strong, malty black teas such as Assam and English Breakfast are traditionally taken with milk.

Is loose-leaf black tea better than tea bags?

Whole loose leaves usually give a fuller, smoother flavor and can be steeped more than once.

Can black tea stain teeth, and how can I prevent it?

Yes, like coffee, it can. Rinsing with water after your cup and regular brushing help.