There are an increasing number of ways to prepare filter coffee, each of which has its own effect on flavor and texture. For the most part though, there are two main ways to brew coffee: percolation and immersion.
With immersion brewing, the coffee is in full contact with the water for the entire duration of the extraction. This enhances the body and aftertaste of a coffee.
One of the most popular immersion brewing methods, particularly in Japan, is the siphon (also known as a siphon or vacuum brewer). This unique coffee maker includes two separate chambers that rely on steam pressure and gravity to extract the coffee.
So how do siphons work and, in turn, how do they affect the flavor and texture of the coffee? To find out, I spoke to two baristas. Read on to learn more about his vision.
You may also like our article on which filter coffee brewing method is best for you.
A brief history of the siphon and other sous vide preparation methods
While the first vacuum coffee maker is believed to have been invented by Loeff of Berlin sometime in the 1830s, siphons became commercially available in the mid-1800s thanks to French inventor Marie Fanny Amelne Massot.
Around the same time, Scottish engineer Robert Napier designed his Napier coffee maker, which also creates a vacuum for brewing coffee. Although the brewer received an award from the Institution of Mechanical Engineers in 1856, it was never patented.
Since then, many types of vacuum coffee makers have entered the market, but the most popular model is the siphon, specifically the Hario siphon, which is widely used in Japanese and Taiwanese coffee shops.
Hirona Yamamoto is a barista at LiLo Coffee Roasters in Osaka, Japan. She is also preparing to compete in the World Siphonists Championship, an event in which competitors craft three siphons and three signature drinks in a 15-minute performance.
“In the past, and even today, the siphon has been an indispensable piece of equipment for coffee shops in Japan,” he explains.
He adds that while the first Kisses Inaugurated in Japan in the mid-18th century, they became more popular after World War II, when the country was going through a period of economic growth.
“As part of this, more coffee shops started opening up, which people used as everyday social spaces,” Hirona tells me. “Because of their aesthetic design, siphons have become a hot item in coffee shops.”
Narumi Sato is the CEO of Belleville Japan, which also operates a location in Paris. She is also the 2016 World Champion Siphonist.
“During this time, the siphon was very popular,” she says. “One of the reasons it has become so common in coffee shops is because baristas can perform other tasks while making coffee with it.”
Narumi adds that while most Kisses Focusing primarily on pour overs, he believes interest in siphoning will continue to grow, especially in the specialty coffee sector.
How does it work?
Unlike most brewing methods, a siphon uses pressurized steam to extract the coffee. Most other coffee brewing methods use time (immersion) or gravity (percolation) to extract the flavors and aromas of the coffee.
By definition, siphons and other vacuum brewing methods brew coffee in an environment where air is removed. Siphons have two brew chambers: an upper chamber, which is where the vacuum is created, and a lower chamber, which is where the brew water is initially added.
The heat source, as well as the siphon design, helps create a vacuum within the upper brew chamber. This is caused by a difference in air pressure. As the water in the lower chamber boils, some of it turns to water vapor, which in turn means its pressure increases.
Since the density of water vapor is much less than that of liquid water, the mixture of air and water vapor in the lower chamber expands. This continues until the spout of the upper chamber connects with the lower chamber, causing water to enter the upper chamber.
When the heat source is turned off, the pressure drops, forcing the brewed coffee back into the lower chamber, but leaving the used grounds behind.
When using any method of vacuum preparation, the extraction time is usually much shorter. This is due to the absence of oxygen and other gases. In this environment, the volatile compounds in the coffee can be extracted much more quickly, as there are fewer gas particles to inhibit extraction.
This is especially noticeable with automated vacuum cold brew methods, which can extract the cold brew in a matter of minutes, rather than hours.
How to prepare a siphon
Although many coffee professionals claim that brewing with a siphon can be complicated and time consuming, Narumi tells me that the method is relatively simple.
- Add water to the lower chamber. Narumi suggests using a 1:15 ratio of 16g coffee (ground slightly finer than for a V60) and 240g water.
- Turn on your heat source (ideally on high heat) and place it under the bottom chamber. Regardless of which brand of siphon you use, most come with a portable heat source, usually a gas burner or infrared lamp.
- As the water heats up, place the filter (either paper or cloth) in the upper chamber and place the spout in the lower chamber. Once the water begins to boil, a buildup of steam pressure will cause it to move into the upper chamber.
- When most of the water reaches the upper chamber, you must stir it vigorously (traditionally with a bamboo paddle or chopsticks) to create a “whirlpool”.
- Add the ground coffee to the water and stir, before placing the lid on the upper chamber to preserve most of the coffee aromas.
Narumi explains that after 25 seconds, the heat source must be turned off, which will cause the brewed coffee to return to the lower chamber. She adds that the total prep time should be between a minute and a minute and a half, making it a much simpler prep method than others.
“When you make a pour-over, you have to fully focus on it for about three minutes,” he explains. “But with a siphon, you only have to focus for 20 to 30 seconds, which makes it a lot easier.”
Why is it so important to stir the coffee when using a siphon?
As with any other preparation method, the correct level of agitation is important if you want to ensure an even extraction. However, according to the World Championship of Siphonists, to achieve the best possible result with a siphon, you should use the double stirring technique.
This is when you first stir the water to create a “whirlpool” in the upper brew chamber, and then stir a second time once you add the coffee to the water.
“The first stir is the most important,” says Narumi. This is because it ensures a more even saturation of the coffee grounds once they are added to the water.
Hirona agrees, saying, “If you don’t allow the grounds to become completely saturated, it’s more difficult to achieve high-quality extraction.”
While the first stirring can be more vigorous, the second should be more gentle to allow the coffee to degas, similar to a bloom when preparing a pour over.
Ultimately, a sign of performing a highly skilled stirring technique is the formation of a dome of coffee grounds at the base of the upper chamber, with larger coffee particles accumulating at the bottom.
How does siphon coffee taste?
When preparing a siphon, the coffee is in full contact with the water during the entire extraction, since it is an immersion preparation method.
However, compared to coffee made using other immersion methods, siphoning creates a different sensory profile, particularly in terms of texture and mouthfeel.
This is mainly due to the vacuum created during the brewing process, as well as the use of a cloth filter, both of which can produce a more improved mouthfeel.
Narumi tells me that this may also be a reason why siphoning is so popular in Japan.
“When I went to the Belleville cafe in Paris, the baristas were describing the taste of the coffee, but not the mouthfeel,” he says. “In Japan, people like to describe the mouthfeel and different foods and drinks.”
This is most likely the result of language differences. Compared to the English language, for example, the Japanese language contains more words to describe mouthfeel.
Narumi adds that there are around 400 words in the Japanese language to describe the mouthfeel. This is most prominent in Japanese cuisine, which tends to focus much more on the texture and consistency of food. By comparison, the English language has around 80.
For example, the word bull bull (which roughly translates to “syrup” in English) describes the texture of the liquid that is slightly thicker than water.
Tips for using a siphon to prepare coffee
Hirona tells me that the siphon is a very versatile coffee maker and can be used by anyone, no matter their level of brewing experience.
“You can make any type of coffee with a siphon,” she says. “It doesn’t matter if the coffee is light or dark roast, or if it’s commercial grade or specialty.”
Narumi agrees, saying that dark roasts often work well with this brewing method.
“This is due to the higher amount of oils in the darker roasted beans,” he explains. “The increased bitterness of these coffees will become fuller, so it can result in a richer tasting coffee.”
Many coffee professionals and home brewers use a cloth filter when siphoning, which allows more oils to be extracted from the coffee, further improving its mouthfeel.
However, if you use a cloth filter, you need to make sure it is clean. Since cloth filters can be reused many times, if they are not properly cleaned and dried after each use, they can quickly attract mold and impart sour flavors to your coffee.
To prevent this, after squeezing out as much water as possible, you can store used cloth filters in the freezer and run them under hot water before using.
The siphon’s distinctive design and unique vacuum brew system make it a great addition to specialty cafeterias and home brew setups.
With their rich history and unique style, it’s clear that siphons have a place in specialty coffee and will continue to do so for the foreseeable future.
Did you enjoy this? then read our article on how stirring affects the preparation of filter coffee.
Photo credits: Hirona Yamamoto, Kaori Umezawa, Takumi Yamashita
Perfect Daily Grind
All Hirona Yamamoto’s quotes are translated from Japanese to English.
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