Coffee & Café
// Total coffee needed total_g = cups × dose_per_cup_g // Expected yield (Italian standard) yield_ml = cups × 25 to cups × 30 // Shots per kg shots_per_kg = 1000 ÷ dose_per_cup_g // Italian standard: 7 g dose shots_per_kg = 1000 ÷ 7 ≈ 142 shots // Extraction parameters (Italian bar) Dose: 7 g (± 0.5 g) Yield: 25–30 ml Time: 25–30 seconds Temperature: 90–92 °C Pressure: 9 bar
The Italian bar standard is 7 g of ground coffee per single espresso shot (tazzina). Commercial espresso machines are typically calibrated for a single dose of 7 g or a double dose of 14 g. Specialty coffee bars may use 8–10 g for a richer extraction.
The Italian standard specifies an extraction time of 25–30 seconds to produce 25–30 ml of espresso. Faster extraction (under-extraction) gives a thin, sour shot. Slower extraction (over-extraction) produces bitter, astringent coffee.
At 7 g per shot, 1 kg of coffee yields approximately 142 single espresso shots. In a busy Italian bar serving 200+ coffees per day, a kg of coffee lasts about half a day.
Standard tamping pressure is approximately 15–20 kg (30–44 lbs) of force. Consistent tamping is more important than hitting an exact number. The tamped puck should be level and compact to ensure even water distribution.
The coffee dose stays the same — 7 g. The difference is in the water volume: a ristretto uses about 15–20 ml water (shorter pull), an espresso 25–30 ml, and a lungo 40–60 ml. The dose does not change; only the extraction volume and time change.