The French press
The French press steeps the grind in all the water, then separates the drink from the grounds by pushing a metal mesh to the bottom of the vessel. It is an immersion without paper: everything that passes through the mesh, oils and fines included, ends up in the cup.
What happens in a French press?
Start the scene or choose a stage. The animation simplifies the mechanism; what follows gives the details and the available references.
Hot water is poured over all the coarse grind at once. The grind rises in a crust, releasing its gases; extraction begins everywhere at the same time.
Read the stages without animation
- All the water at onceHot water is poured over all the coarse grind at once. The grind rises in a crust, releasing its gases; extraction begins everywhere at the same time.
- ImmersionWith the lid on and the filter raised, the grind bathes in all the water. Concentration rises quickly, then more and more slowly toward a plateau, at around 21% extraction in the laboratory.
- The plunger descendsThe plunger is pressed down slowly; the mesh, edged with its spring, slides against the wall. The spring follows the irregularities of the glass: the grounds are pushed to the bottom without slipping past the edges.
- The grounds packed at the bottomThe mesh stops on the packed grounds. The oils and the finest particles pass through the wire mesh and stay in the liquid.
- Serve at onceThe whole carafe is poured into the cups. Grounds left in contact would keep extracting; once emptied, the carafe stops there.
To remember: The plunger does not press the coffee: it puts the grounds away at the bottom. What passes the mesh, oils and fines, makes the body of the cup.
In history: Milan, 1928 to 1934: Paolini, Calimani and Moneta, then Cassol for the seal; a French ancestor of 1852 remains unverified.
Read the full article and its sources ↓History
The method descends from infusion without boiling, born in France in the early 18th century with a fustian bag, a cloth in which the grind was put; Ukers dates it to 1710 in one chapter and 1711 in another (source 1, ch. XXXIV and XXXVI). In 1722, Broadbent already advises pouring boiling water over the powder, in a stoneware or silver pot, and letting it steep five minutes before the fire (source 1, ch. XXXVI). The perforated disc on a rod appears as early as 1806 in Hadrot's French patent, but on a pot where the water passes through the coffee (source 1, ch. XXXIV).
A French patent of 1852 in the name of Mayer and Delforge, with no seal around the filter, is cited everywhere as the first ancestor; it could not be read, and the information comes from Wikipedia, which cites the New York Times (source 6). The same goes for a Paquet patent of 1924.
The first patent read is Milanese. Ugo Paolini filed on April 2, 1929 in the United States, on an Italian priority of April 2, 1928, an “apparatus for preparing infusions, in particular coffee,” granted on March 24, 1931: a vessel, a lid, a filtering member “in the form of a piston” mounted on a rod, and a spring wound around the rod that holds the filter at the desired height. The water boils in the vessel with the grind, the rod is pushed down, and the coffee is poured without removing the lid. Paolini assigned half of his rights to Attilio Calimani and the other half to Giulio Moneta (source 2), in whose names the Swiss and French patents of the same priority were published in 1929 and 1930 (source 3).
The seal comes next, and for a reason. On March 2, 1934, Bruno Cassol, also a Milanese, filed in Italy a sliding filter whose tightness relies on a helical spring fixed all around and covered with gauze: coffee is better prepared in glass or ceramic than in metal, but the inside of a glass or ceramic vessel never has an exact diameter, and the spring follows these irregularities. His patent was assigned to Gemma Barelli Moneta (source 4).
Faliero Bondanini filed in Switzerland, on February 25, 1955, a “filter coffee pot” that cites Cassol's patent; the American version was granted in 1959 (source 5). According to Wikipedia, the French clarinet maker Martin produced it under the brand Melior, and the Danish company Bodum bought the rights to the Chambord in 1983 and then Martin in 1991 (sources 6 and 7), dates not read in a primary document.
The motion
The coffee maker consists of a glass carafe, a lid pierced by a rod, and a wire-mesh filter edged with a spring that rubs against the wall (source 4). In English it is called the French press; here it will simply be called the plunger pot. The coarse grind goes into the carafe, all the hot water is poured in, the lid is set on with the filter raised, and one waits.
After the chosen time, the rod is pressed down slowly: the mesh pins the grounds to the bottom, and the coffee is poured at once. The SCA standard, from the international specialty coffee association, allows the French press for the descriptive evaluation of a coffee, at 55 to 60 g of coffee per liter of water, with a grind suited to the method (source 8).
The settings
- GrindCoarse, suited to the method (source 8); no standardized particle size distribution found.
- Dose55 to 60 g of coffee per liter in SCA standard 102-2024 (source 8); Broadbent 1722: two ounces per quart, or about 50 to 60 g per liter depending on the quart used (calculation, source 1, ch. XXXVI).
- Brew ratioAbout 1:17 to 1:18 (source 8).
- TemperatureNot standardized; between 80 and 99 °C, temperature changes the speed of extraction in immersion, not the yield reached at equilibrium (source 9).
- TimeFive minutes for Broadbent in 1722, about six minutes in the Viennese urn of 1922 (source 1); no standardized time found.
- PressureAtmospheric: the plunger separates the grounds, it does not force water through the coffee.
What it has going for it
- The metal mesh can be reused indefinitely: no paper or consumable.
- Immersion is forgiving: at equilibrium, the extraction yield barely depends on the brew ratio, the grind or the temperature between 80 and 99 °C (source 9), so an imprecise motion changes little in the result when time is left to do its work.
- The oils and the finest particles pass into the cup and give a full body (source 10).
What is held against it
- The mesh lets the fines through: about 1.5 g of fines per liter is measured in a French press coffee (source 10), hence the sediment at the bottom of the cup.
- It also lets the diterpenes through: a light roast prepared in a French press releases 6.5% of its cafestol, the highest rate of four methods compared (source 11), about 70% of the cafestol drunk is absorbed by the intestine (source 13), and six cups a day of boiled or French press coffee remain associated with higher cholesterol (source 12).
- The grounds stay in the carafe: concentration keeps rising up to a plateau reached at around twenty minutes (source 9), and the coffee left on the grounds does not freeze at the moment the plunger was pressed.
- Everything rests on the contact of the spring against the wall: it is precisely because glass does not have an exact diameter that the spring had to be invented (source 4), and a worn seal lets the grounds through.
What it gives in the cup
The cup has body, a veil of particles and a sometimes oily surface: nothing holds back the oils or the smallest particles (source 10). In the laboratory, a one-liter immersion plateaus at around 21% extraction (20.7% on average), and its concentration is inversely proportional to the brew ratio: 1.36% dissolved solids at 99 °C for a ratio of 15, whatever the grind between 579 and 1,311 microns median size (source 9).
The authors caution that two drinks of the same concentration can taste different, and that measuring dissolved solids ignores the oil droplets and suspended colloids, which count for a lot in a French press cup (source 9). Stopped after a few minutes, before the plateau, the French press gives a cup less extracted than equilibrium.
Anecdotes
- In the restaurants of Vienna in 1922, a large urn steeps the coffee for about six minutes, then a screw lifts a metal sieve whose thrust forces the liquid through a cloth bag: a plunger in reverse (source 1).
- In Paolini's patent, the water boils in the carafe with the coffee, and the coffee is poured through a spout without lifting the lid: the first patented plunger was also a small decoction (source 2).
The sources for this sheet
- 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. XXXIV (fustian bag, Hadrot 1806), ch. XXXV (Viennese urn), ch. XXXVI (infusion of 1711, Broadbent 1722) · online · primary
- Ugo Paolini (assigning half to Attilio Calimani and half to Giulio Moneta), US patent 1,797,672, “Apparatus for preparing infusions, particularly for preparing coffee,” filed April 2, 1929, Italian priority of April 2, 1928, granted March 24, 1931 · online · primary
- Attilio Calimani and Giulio Moneta, Swiss patent CH 139142 (filed March 27, 1929, published April 15, 1930) and French patent FR 672330 (filed March 29, 1929, published December 26, 1929), Italian priority of April 2, 1928 · online · primary · reading: bibliographic records only
- Bruno Cassol (assigning to Gemma Barelli Moneta), US patent 2,053,021, “Apparatus for filtration of infusions,” Italian priority of March 2, 1934, granted September 1, 1936 · online · primary
- Faliero Bondanini, US patent 2,900,896, “Coffee filter pot,” Swiss priority of February 25, 1955, filed July 16, 1957, granted August 25, 1959 · online · primary · reading: record and claims
- Wikipedia (en), “French press,” accessed October 21, 2026, citing D. Engber, “Who Made That French Press?” The New York Times, May 30, 2014 · online · secondary
- Wikipedia (en), “Bodum,” accessed October 21, 2026, citing C. Robertson, The Little Book of Coffee Law, American Bar Association, 2010, p. 229, and the manufacturer's site · online · secondary
- Specialty Coffee Association, SCA Standard 102-2024, Coffee Value Assessment: Sample Preparation and Tasting Mechanics, 2024, § 5.3 · online · primary
- J. Liang, K. C. Chan, W. D. Ristenpart, “An equilibrium desorption model for the strength and extraction yield of full immersion brewed coffee,” Scientific Reports, 11, 2021, 6904, doi:10.1038/s41598-021-85787-1 · online · primary
- 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)
- 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)
- 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)
- B. De Roos, S. Meyboom, T. G. Kosmeijer-Schuil, M. B. Katan, “Absorption and urinary excretion of the coffee diterpenes cafestol and kahweol in healthy ileostomy volunteers,” Journal of Internal Medicine, 244 (6), 1998, pp. 451-460, doi:10.1046/j.1365-2796.1998.00386.x · online · primary · reading: abstract only (PubMed)