Boiled coffee

History

Decoction, that is, extraction by boiling, is the “old-fashioned” coffee according to Ukers. In 1722, the merchant Humphrey Broadbent attacks the practice of the London coffeehouses, boiling an ounce of powder in a quart of water, and argues for steeping (source 1, ch. XXXVI).

In the American colonies, before 1800, coarsely pounded coffee is commonly boiled for a quarter of an hour to half an hour. In 1844, a household manual still advises twenty to twenty-five minutes of boiling and clarification with isinglass or egg (source 1, ch. XXXVI); in 1881, Francis Thurber still defends the egg method (source 11), in a book that Ukers dates to 1883.

The first measured comparisons condemn it. In 1915, at Ukers's request, the Mellon Institute of Pittsburgh compares nine devices: boiling gives the most caffeine and what was then called “caffeotannic acid,” and the drink is more pleasant between 195 and 200 °F, that is 90 to 93 °C, than at the boil. In 1917, a cup test by the Tea and Coffee Trade Journal ranks the boiling pot last, behind the paper filter, the cloth filter, the glass filter and the percolator (source 1, ch. XXXVI).

Scandinavia kept it for a long time. In 1922, in Norway, the boiling method “has many followers”: the coffee is thrown into a large open copper kettle, set as it is on a board on the table of modest homes; in the Australian bush, the water boils in the camp can, the powder is thrown in, and the coffee is ready when the water returns to a boil (source 1, ch. XXXV). In Norway, electric filter coffee makers only became common in the second half of the 20th century (source 2).

It is in Norway that the method changed medicine. In 1983, the Tromsø study, of 14,581 adults, links coffee consumption to total cholesterol, from 5.56 mmol/L in men who drink less than one cup a day to 6.23 in those who drink more than nine (source 4). In 1989, a Dutch trial shows that boiled coffee raises cholesterol by 0.48 mmol/L in nine weeks, and filtered coffee does not (source 5). In 1994, cafestol is identified as the culprit (source 6).

The motion

All that is needed is a kettle or a saucepan, water and coarsely ground coffee: in 1922, the “coarse” grind is the one the trade intends for boiling (source 1, ch. XXV). In Sweden it is called kokkaffe, in Norway kokekaffe, that is “cooked coffee”; here we will say boiled coffee. The water is brought to a boil, the grounds are thrown in, left to come back to the boil and the pot is taken off the heat (source 1, ch. XXXV).

What remains is to bring the grounds down. Broadbent adds a spoonful of cold water, which “immediately precipitates the heavy parts” (source 1, ch. XXXVI); Thurber mixes a whole egg, shell included, into the grounds, boils for ten to fifteen minutes, lets it rest for three minutes and strains through a fine sieve (source 11). It is then poured gently, without stirring up the bottom.

The settings

• GrindCoarse, the class intended for boiling in 1922 (source 1, ch. XXV).
• DoseOne tablespoon to a pint of water in 1844 (source 1, ch. XXXVI); one ounce to a quart in the London coffeehouses of 1722, that is about 25 to 30 g per liter depending on the quart chosen (calculation, source 1, ch. XXXVI).
• Brew ratioAbout 1:33 to 1:41 for the London practice of 1722 (calculation, source 1); not standardized.
• TemperatureBoiling, about 100 °C at sea level; the Mellon Institute found as early as 1915 that the drink was better between 90 and 93 °C (source 1, ch. XXXVI).
• TimeFrom a simple return to the boil (Australia, source 1, ch. XXXV) to 10 or 15 minutes (Thurber, source 11) and 20 to 25 minutes (1844 manual, source 1, ch. XXXVI).
• PressureAtmospheric.

What it has going for it

• All it takes is a vessel and a fire, which made it the coffee of camps, of the bush and of homes without equipment (source 1, ch. XXXV).
• A single kettle serves a whole table and is carried to the table as it is (source 1, ch. XXXV).
• Boiling extracts a great deal: in 1915, it gave the drink highest in caffeine of the nine devices compared (source 1, ch. XXXVI).

What is held against it

• Boiling carries off a large share of the aromas with the steam and hydrolyzes part of the insoluble matter into bitter compounds; reheating the coffee spoils it further (source 1, ch. XVII).
• In the cup test of 1917, the boiling pot came last of the five devices for color, flavor, body and aroma (source 1, ch. XXXVI).
• It is the drink richest in diterpenes: 7.2 mg of cafestol and as much kahweol per cup of Scandinavian boiled coffee (source 7), with 2 to 5 g of fines per liter (source 8); nine weeks of boiled coffee raise cholesterol by about 10% (source 5).
• As late as 2015-2016, in Tromsø, drinking six or more cups a day of boiled coffee or French press coffee remains associated with a cholesterol level higher by 0.30 mmol/L in women and by 0.23 mmol/L in men (source 9).

What it gives in the cup

The cup is heavy, cloudy and bitter: boiling pulls bitter compounds out of the insoluble matter (source 1, ch. XVII), and fines and oils stay in the liquid (source 8). Relative to the cafestol in the grounds, boiled coffee from a light roast extracts 5.84%, almost as much as the French press (source 10).

No recent measurement of concentration or yield specific to boiled coffee was found.

Anecdotes

• The first written mention of coffee in Norway is a kettle: in 1694, the post-mortem inventory of the customs controller Nicolai Flyg lists, among his goods, a coffee kettle (source 2).
• The Nordic Museum in Stockholm keeps the copper coffee kettle, with its rounded belly and domed lid, that belonged to Inga Maria Nutti, of Liedakka, in the Sami village of Lainiovuoma; the curator Ernst Manker brought it into the collections on November 8, 1943 (source 3).
• Francis Thurber dedicates his 1881 book to the man who runs the buffet at the Poughkeepsie station, whose name he admits he does not know, because he serves “year after year” an ideal cup of coffee (source 11).

The sources for this sheet

1. William H. Ukers, All About Coffee, New York, The Tea and Coffee Trade Journal Company, 1922 (local transcription 1922_Ukers_All_About_Coffee_UTF8.txt), ch. XVII (chemistry of boiling), ch. XXV (grind classes), ch. XXXV (Norway, Sweden, Australia), ch. XXXVI (Broadbent, colonies, Thurber, Mellon Institute, 1917 test) · online · primary
2. Lokalhistoriewiki (Norsk lokalhistorisk institutt), “Kaffi,” accessed October 21, 2026 · online · secondary
3. Nordiska museet, Stockholm, copper coffee kettle (kaffepanna), inventory no. NM.0228818A-B, entered November 8, 1943, DigitaltMuseum record · online · primary
4. D. S. Thelle, E. Arnesen, O. H. Førde, “The Tromsø heart study. Does coffee raise serum cholesterol?” New England Journal of Medicine, 308 (24), 1983, p. 1454-1457, doi:10.1056/NEJM198306163082405 · online · primary · reading: abstract only (PubMed)
5. A. A. Bak, D. E. Grobbee, “The effect on serum cholesterol levels of coffee brewed by filtering or boiling,” New England Journal of Medicine, 321 (21), 1989, p. 1432-1437, doi:10.1056/NEJM198911233212103 · online · primary · reading: abstract only (PubMed)
6. M. P. Weusten-Van der Wouw et al., “Identity of the cholesterol-raising factor from boiled coffee and its effects on liver function enzymes,” Journal of Lipid Research, 35, 1994, p. 721-733, PMID 7911820 · online · primary · reading: abstract only (PubMed)
7. G. Gross, E. Jaccaud, A. C. Huggett, “Analysis of the content of the diterpenes cafestol and kahweol in coffee brews,” Food and Chemical Toxicology, 35 (6), 1997, p. 547-554, doi:10.1016/s0278-6915(96)00123-8 · online · primary · reading: abstract only (PubMed)
8. R. Urgert, A. G. Schulz, M. B. Katan, “Effects of cafestol and kahweol from coffee grounds on serum lipids and serum liver enzymes in humans,” American Journal of Clinical Nutrition, 61 (1), 1995, p. 149-154, doi:10.1093/ajcn/61.1.149 · online · primary · reading: abstract only (PubMed)
9. Å. L. Svatun, M.-L. Løchen, D. S. Thelle, T. Wilsgaard, “Association between espresso coffee and serum total cholesterol: the Tromsø Study 2015-2016,” Open Heart, 9 (1), 2022, e001946, doi:10.1136/openhrt-2021-001946 · online · primary · reading: abstract only (PubMed)
10. C. Zhang, R. Linforth, I. D. Fisk, “Cafestol extraction yield from different coffee brew mechanisms,” Food Research International, 49 (1), 2012, p. 27-31, doi:10.1016/j.foodres.2012.06.032 · online · primary · reading: abstract only (Semantic Scholar, OpenAlex)
11. Francis B. Thurber, Coffee: From Plantation to Cup, New York, American Grocer Publishing Association, 1881 (local copy 1881_Thurber_Coffee_From_Plantation_to_Cup.pdf) · online · primary