Coffee and tea at home: ratios, temperature and timing like a café

Coffee is a roasted seed, and its main enemy is time. Flavour peaks 5–7 days after roasting and holds for about a month. Ground coffee loses most of its aroma within 15–30 minutes. So the best thing you can do for flavour is buy beans with a roast date on the bag and grind just before brewing.

Arabica is softer, with acidity and a complex aroma. Robusta is more bitter and stronger, has twice the caffeine and gives a thick crema. Espresso and cezve coffee often use blends; filter coffee usually single-origin arabica.

The base ratio for most methods is 1:16 — 60–65 g coffee per litre of water, or about 15 g per 250 ml mug. For stronger coffee move towards 1:14, for milder to 1:17. Kitchen scales make coffee predictable: a spoon of ground coffee can weigh anything from 5 to 10 g.

Coffee is 98% water, so the water matters. Use filtered or bottled, not distilled: without minerals coffee tastes flat. The temperature should be 90–96 °C: let a boiled kettle stand for 30–60 seconds. Boiling water scorches coffee and makes it bitter.

Grind size controls extraction speed — how quickly water washes flavour out of the coffee. Acids come out first, then sweetness, and bitterness last. Sour, hollow coffee is under-extracted: the grind is too coarse or the time too short. Bitter, astringent coffee is over-extracted: the grind is too fine, the water too hot or the time too long.

Per 100 ml cold water — 7–8 g of the finest-ground coffee (a heaped teaspoon). Add sugar at the start if you want it. A pinch of salt softens bitterness; cinnamon or cardamom are optional.

Stir and set over the lowest heat. The slower it heats, the better the extraction and the thicker the foam — ideally 2–3 minutes. When the foam starts to rise and a crack appears in the middle, take it off the heat at once. It must not boil: boiling destroys the foam and adds bitterness.

French press: 30–32 g coarse coffee per 500 ml water. Pour on water at 93–95 °C, stir and put the lid on without pressing. After 4 minutes, skim the crust off the top with a spoon and slowly press the plunger. Pour straight away — coffee left on the grounds keeps extracting and turns bitter.

Moka pot: fill the base with hot water up to the valve — that way the coffee cooks less on the hob. Fill the basket with coffee in a mound and level it, but don't tamp. Set over medium heat with the lid open. As soon as the coffee runs paler and you hear a gurgling hiss, take it off the heat and cool the base with a cold towel.

Pour-over: 15 g medium-fine coffee per 250 ml water. Rinse the paper filter with hot water to remove the papery taste. First pour 30–40 ml of water and wait 30–40 seconds — the coffee blooms, releasing carbon dioxide. Then pour in a thin spiral. Total time 2.5–3.5 minutes.

Cold brew: 100 g coarse coffee to 800 ml cold water (1:8). Stir, cover and leave in the fridge for 12–18 hours. Strain through a paper filter. You get a concentrate that is smooth, sweetish and barely acidic. Dilute 1:1 with water or milk and serve over ice. It keeps for a week.

The ideal milk temperature is 60–65 °C: hot, but you can still hold the cup. Above 70 °C milk tastes cooked and the foam collapses.

Cold milk with 3.2–3.5% fat froths best: protein makes the foam and fat makes it velvety. Warm the milk and froth it in a French press: 15–20 quick strokes of the plunger. Or with a handheld frother, or just in a jar with a lid — shake for 30 seconds, then take the lid off and microwave for 30 seconds to stabilise the foam.

For plant milk, buy the barista version: ordinary almond or oat milk is low in protein and the foam soon falls apart.

Boiling water stews delicate tea: green turns bitter and grassy, white loses its aroma. Each type has its own temperature and time.

Warm the teapot with boiling water and pour it out: cold porcelain draws off heat and the tea brews worse. Add the leaves and pour on water at the right temperature.

Don't overdo it: every minute more tannins come out of the leaves and the tea turns harsh and astringent. When the time's up, pour all the tea into cups or another pot. Leaves left in water keep brewing.

Tea bags usually hold fine dust: they brew faster (2–3 minutes) and don't like being squeezed with a spoon. Loose leaf opens more slowly and stands up to several infusions.