Table 1

Preparation type definitions, caffeine (CAF), chlorogenic acids (CGA) and diterpene concentrations, classification within NDNS and derived coffee unit examples

Coffee preparation typeCAF mg/mLSourceCGA mg/mLSourceDiterpenes (cafestol plus kahweol) mg/LSourceCAF+CGA mg/mLNDNS databaseCoffee unit of typical drink
Instant
(concentrated brewed coffee granules or powder diluted with boiling water)		0.33
(0.10–0.56)*		21 home brewed8 0.51
(0.28–1.22)*		Eight lab prepared9 3.8†‡Three lab prepared sampled in duplicate10 0.84Volume of diluent for instant coffee1 unit in 227 mL mug
Decaffeinated instant§
(instant with CAF removed by processing)		0.01
(0.00–0.01)*		Three home brewed8 0.46Assumed 10% less than caffeinated11 3.7†‡Three lab prepared sampled in duplicate10 0.47Volume of diluent for instant coffee0.6 units in 227 mL mug
Espresso
(pressurised water passing through finely ground coffee)		3.11
(1.40–8.92)*		32 shop bought9 (Scotland)1.64
(0.22–10.54)*		32 shop bought9 (Scotland)4.6†‡Five lab prepared sampled in triplicate12 4.75Strong infusion<65 mL0.7 units in 30 mL espresso
Filter
(coffee and water passing through a filter, commonly paper)		0.62
(0.22–0.75)*		14 home brewed8 0.81†‡One lab prepared sampled in triplicate13
(Arabica)		0.3†‡One lab prepared sampled in triplicate12 1.43Strong infusion
≥65 mL and all weak infusions		1.7 units in 227 mL mug
French press
(also known as cafetière—coffee pot with plunger)		0.52†
(SD of the mean 0.02)		Three lab prepared sampled in triplicate4 0.65†
(SD 0.002)		Three lab prepared sampled in duplicate
14 		27.9†‡
(based only on cafestol)		Three lab prepared sampled in duplicate15 1.17Not differentiated in database1.4 units in 227 mL mug
Cappuccino
(espresso and frothed milk)		0.72
(0.49–
1.24)*		20 shop bought9 0.41*
(0.06–0.99)		20 shop bought9 9.2Extrapolated from espresso1.13Separate category2 units in 354 mL cup
Latte
(espresso and steamed milk)		0.72Extrapolated from cappuccino0.41Extrapolated from cappuccino9.2Extrapolated from espresso1.13Separate category1.4 units in 240 mL latte glass
Mocha
(espresso and chocolate and steamed milk)		0.72Extrapolated from cappuccino0.41Extrapolated from cappuccino9.2Extrapolated from espresso1.13Separate category2 units in
354 mL cup

  • *Median (minimum to maximum).

  • †Mean.

  • ‡Variability not available/calculable for combined measure.

  • §Other decaffeinated coffee types not included in table.

  • NDNS, National Diet and Nutrition Survey.