Straight to the Point
When I was a barista at a busy downtown Chicago coffee bar, we made every cup of coffee to order, by hand, and offered three different brew methods daily: pourover, Chemex, and siphon. The two siphon rigs framing either side of our pourover bar were an instant draw: sell one siphon-brewed coffee, and the crowd gathered around your mysterious boiling water globes would likely order another.
Introduced in 1915, the Silex coffee maker was the first mass-produced coffee siphon in the United States and was quite common until the coffee percolator became their dominant model. In 1939, Silex even built a 7-foot tall glass siphon brewer to show off at the World’s Fair. But siphon brewing goes back even further than that: in the 1830s, the balance brewer was constructed to capture the public’s newfound love of vacuum technology. An early siphon design, the balance brewer gathered a lot of attention with side-by-side chambers for coffee and water affixed to a balance arm that tipped as the weight of the chambers shifted during the brewing process.
It’s not really a surprise that the siphon fell out of fashion when easier brew methods became widely available. It’s a particularly finicky brewing process that requires the user to time their water heating, check the brew temperature, remove and replace the top chamber, stir the coffee, and remove from the heat source in just the right manner to trigger the vacuum action. It takes time, knowledge, and concentration to brew coffee on a siphon, and, because of that, I wanted to include as much information as I could about this brew method before I felt comfortable recommending any models for home use.
The Winners, at a Glance
The Best Overall Coffee Siphon: Yama 5-Cup Stovetop Siphon
A flat base for faster, even heating, a widemouth for easy filling, and a sturdy handle for moving on and off a heat source make the Yama 5-Cup Stovetop Siphon our top choice for at-home use, especially if you have a gas range.
The Best Electric Coffee Siphon: Klarstein Syphon Vacuum Coffee Maker
For those who don’t have a gas or electric stovetop, the Klarstein Syphon Vaccuum Coffee Maker comes with an electric heating base that has built-in digital temperature controls.
- Cold Water Test: In order to test how long each brewer took to boil, I filled the siphon’s bottom chamber with 600 grams of cold water. I then set each model's heat source to the highest setting possible without the flame growing wider than the base (which was medium on my gas range), recording the time it took for the bottom chamber to reach boiling.
- Hot Water Test: To measure the difference in heating times, I repeated the cold water test but swapped out 600 grams of water just off the boil before setting the chamber to heat on the highest possible setting. I then recorded the time it took for the bottom chamber to reach boiling.
- Taste Test: To evaluate the brewing potential of each coffee siphon, I set about to dial in a standard brew recipe and repeat it in each brewer. I used a ratio of 30 grams of coffee for 500 grams of water, and ground the beans at a medium-fine setting using a burr grinder. I first boiled a kettle of water, then set the bottom chamber on a scale and poured 500 grams of water into the chamber. I set the top chamber into the bottom chamber, but did not seal it right away. I then set the siphon on a heat source, let the water get close to boiling, and then inserted the top chamber fully so the water would be close to an ideal 200ºF brewing temperature. After checking the water temperature with a thermometer, I added the coffee and stirred for 10 seconds to incorporate the grounds. The coffee was allowed to brew for one minute and 15 seconds before it was removed from the heat source, stirred one last time to break up any coffee crust, and set aside to let the siphon action pull the coffee through the filter. Once it cooled, I tasted each coffee and evaluated it for sweetness, acidity, body, finish, and overall flavor quality.
- Taste Test Two (Winners-Only): In order to establish a definitive brewing process for the best coffee siphons, I adjusted multiple variables, like grind size, brew ratio, brew time, and brew temperature in order to dial in the best tasting coffee possible.
- Usability Tests: Throughout testing, I evaluated each siphon for build quality, ease of operation and cleaning, and any other observations about how each brewer functioned.
The Science Behind Coffee Siphons
In order to fully evaluate these coffee siphons, I felt like I needed to know more about how they work on a scientific level. Generally, siphons have a two chamber system: a bottom flask (which you fill with water) and a top chamber with a filter (where you add the coffee). As you boil the water in the bottom chamber, it moves up a glass tube into the top chamber, where it saturates the coffee and steeps. Once you remove the heat source, it creates a vacuum that then sucks the brewed coffee back down through the filter, leaving you with filtered brewed coffee now in the bottom chamber and spent grounds in the top. However, I still felt I needed a better grasp on the science behind this.
Luckily, I knew just the person to ask. Christopher Hendon is an Assistant Professor of Chemistry at the University of Oregon and also has serious coffee credentials as co-author of Water For Coffee, (now out of print). His work in the lab has published papers on the fracturing of coffee during grinding as well as repeatability in espresso shots.
“The maximum density of water is reached at about four degrees Celsius,” Hendon says. “Which means it’s smallest at that point. If you boil the water, the water is going to turn into gas and fill a space, so water is always expanding when you heat it up. In a siphon, you’re using a round-bottom flask for heating water and in principle, before you add the top of the siphon on, creating a seal. You’re just heating it in one atmospheric pressure with basically infinite volume in which that water can occupy.”
What he means, in simpler terms, is that as the boiling water begins to turn into water vapor and transform into gas, it can escape the top chamber and dissipate throughout, theoretically, the entire universe. Which is a trippier concept then I expected I would have to contemplate when talking about coffee brewing. There’s nothing holding the water vapor back, and, eventually all of the water will evaporate in the bottom chamber.
“With a siphon brewing method, you’re going to put an impermeable plug on the top of that chamber. If you heat up water in a closed space, you’re going to have more water molecules in the air floating above the liquid water molecules pushing on the sides of the wall,” Hendon told me.
So, as you heat water and it starts to expand, the siphon’s lower chamber pressurizes and water is forced up through the glass pipe and filter, filling the top chamber, where the coffee brewing happens. And from there it gets a little more complicated. Hendon explained that it’s common to see bubbles in the top chamber floating upwards and to assume that the water in the top chamber is boiling, but that’s not actually the case. In a siphon, there’s always a small amount of water left in the bottom chamber, and that water is directly exposed to the heat source, so it boils. As it does, the water vapor it produces travels up the pipe and turns into bubbles once the water vapor runs into the hot brewing water in the top chamber.
If the water in the top chamber isn’t boiling, then how hot is it? Well, that depends. If you seal off the top chamber early, the water might only be 150ºF or so as it rises to the top. If you wait until the water is boiling in the bottom chamber, however, the water in the top chamber can be anywhere between 204-210ºF. There’s actually a delay—for the first minute or so, water moves slowly, initially pushed by the expanding air pressure. Once the water hits its pressure limit, the rest of the brew water travels to the top chamber fast.
“The real business happens when you pull it off the heat. As the molecules that are in that lower vessel start to cool down, they’re going to stop impacting the glass walls as frequently, which can be viewed as lowering pressure,” Hendon says. Opposed to the outside world, the mid-brew siphon's under relatively high pressure, and as the pressure lowers, it needs to pull from somewhere. The only place it can do so is from is that vessel up top which now contains brewed coffee, which then pulls the brewed coffee through the filter, leaving the solids up top and the filtered, brewed coffee in the bottom.
What Standard Siphon Instructions Get Wrong (and What to Do Instead)
Okay. That was a lot. But it was also necessary for developing our modern step-by-step siphon brew guide, because what I learned from Hendon helped break up a lot of misconceptions about how coffee siphons work, and their general brewing instructions. The average guide provided by coffee siphon manufacturers instructs the user to fill the bottom with water, affix the top chamber immediately and fill with coffee, and then set to a heat source.
We know from Hendon’s explainer that this is flawed. Ideal coffee brewing temperature is between 195-205ºF, and with a sealed top chamber, that water is going to start to travel upwards at around 150ºF. That water will also hit the coffee early, meaning that the brew water will start to saturate the grounds before it’s made its way all the way up the siphon, creating an inconsistent extraction between our ground coffee and only some of the brewing water.
Most siphon brewers also recommend a steep time of around one to one-and-a-half minutes, which is considerably shorter than standard brew times. Even with the draw down, the total coffee and water contact time would be limited to around two to two-and-a-half-minutes—much shorter than the 3- to 4-minute recommended brew time for pourover, or 5- to 10-minute brew time recommended for a French press.
Instead, here's how I recommend brewing in a siphon (I'll go into the how's and why's of each of these points more below):
- Add boiling water to the bottom chamber, then turn on the heat source to medium until the water travels to the top. Double check the brew temperature isn’t too hot or cold (a thermometer helps here). If it's below 190ºF, you can leave the heat source on until the temperature rises, and if it's above 205ºF, you can stir the water with a paddle until it cools down.
- Add your ground coffee and gently stir 10 times in a zig-zag pattern, making sure to get the grounds fully saturated, then let the coffee steep for two minutes with the heat source set to low.
- After that time is up, remove the siphon from the heat source, stir 10 more times in a zig-zag patten.
- As it cools, the lower vessel will pull the brewed coffee through the filter attached between the two chambers.
What We Learned
Coffee From a Siphon Can Taste Delicious
I was impressed by how every siphon seemed to highlight coffee's sparkling acidity, more so than the pourover I made that morning. While I don't feel comfortable stating that all coffee brewed on a siphon will taste a certain way, I will say that I thoroughly enjoyed all the test brews I made, and there might be something to the fact that a siphon is one of the only brew methods (when brewed per my adjusted instructions) that maintains the ideal brew temperature range of 200-205ºF during the entire brewing process.
How to Avoid Any Boiling Over
During my water heating tests, I let the water in the Hario Next siphon hit a rolling boil with the butane burner as its heat source. To match the same amount of water as every other siphon, I nudged it past the max fill capacity just slightly, but that was enough for the rolling boil to escape the bottom chamber and splash all over the counter.
This can also happen if the water in the bottom chamber is superheated. Superheating occurs when water is heated beyond boiling in a smooth sided vessel, like glass. Bubbles need nucleation sites, basically any sort of solid or imperfection to latch onto, for them to be able to form. If water is heated beyond boiling in a smooth sided vessel, it risks an extreme rapid boil over once a nucleation site is introduced.
Because of this, you should never heat the bottom chamber of a siphon without the top chamber at least partially inserted. The dangling chain from the filter assembly can act as a nucleation site easily, allowing bubbles to form safely and cut down the risk of boiling over.
Water Temperature Management Was Crucial to Cup Quality
If the water is allowed to boil in the bottom chamber, it turns out it’s really, really hard to get it to cool down. As water near boiling travels up to the top chamber, it becomes heated by the boiling water sending steam up from the bottom chamber. I found that if I waited too long, the water in the top chamber would be between 204-210ºF—hotter than our ideal temperature range of 200-205ºF .
The best way to manage water temperature is to boil it in a separate kettle and add it to the bottom chamber just before brewing. While this may seem finicky, it actually takes less work than boiling water directly in the siphon, which requires you to watch it the entire time in order to have precise temperature management. Boiling water in a separate kettle lets you multitask, setting up your siphon filter or grinding coffee knowing the water temperature won’t get too hot.
Water just off the boil poured into the bottom chamber will drop to around 180-190ºF, which is just below our ideal brewing temperature. However, since the water in the top chamber will continue to heat, you can affix the top chamber fully right away and get the siphon on its heating source. The water will start to travel up immediately, and will be around 180-185ºF in the top chamber once it’s finished its journey. From there, you can easily turn the heat source higher to gently raise the temperature of the water in the top chamber to around 195ºF before adding the coffee. It’s best to check this with an instant-read thermometer before adding the coffee.
Excess Agitation and Heat Were No Good
Once the coffee is added to the top chamber, it’s necessary to stir to incorporate the coffee fully. Any amount of agitation, however, can cause the coffee to extract at different rates. Think about making lemonade: the more you stir, the quicker the sugar dissolves. With coffee, the more agitation, the more it will extract. Any amount of stirring should be gentle and timed for consistency. I settled on 10 seconds in a soft zig-zag pattern, which allowed the coffee to be fully saturated into the brew water.
Rising bubbles from the bottom chamber, however, can also cause excess agitation. If the heat source is turned too high, large, aggressive bubbles will rise up like a powerful jacuzzi jet and toss the coffee grounds around. It’s important to dial down the heat source to its lowest setting after the coffee is added: as the coffee forms a crust, it’ll create an insulating layer that will maintain your ideal brew temperature. A lower heat setting can maintain full pressure while only creating a gentle influx of tiny bubbles.
The coffee should be stirred one more time, at the end of the brew cycle, to break up the forming crust and allow the grounds to be fully mixed in the brewing water during the draw down. Again, a gentle, zig-zag stirring pattern for 10 seconds will allow the grounds to gently saturate while creating a system of consistency.
Brew Times Were Flexible
Coffee siphons are a form of immersion brewing. That means that the coffee and water are allowed to saturate, in a mostly static environment, during the brew cycle. With immersion brews, the total brew time is more flexible, because you don’t have a constant influx of new brewing water rinsing the grounds like you do with drip coffee or pourover brewing. While many siphon guides advocate for short steeps, I found that there wasn't a huge difference in the extraction of the coffee across a variety of brew times. Ultimately I settled on a 2-minute steep before killing the heat, which usually created a total contact time of around three-and-a-half minutes. I’m sure that one could create a recipe that works for longer or shorter steep times, but in all my testing, two minutes created a very repeatable brew process.
Brew Ratios Needed More Consideration
No matter what, that water at the bottom of the chamber is going to dilute what comes through the filter from the top chamber. Because of this, I found the best tasting results came from using a slightly stronger brewing ratio of 1:15—one part coffee to 15 parts water. Siphons are a form of immersion brewing, like a French press, so they tend to brew better at stronger ratios. My first brew tests used a pourover ratio closer to 1:16, and I found that while the coffee tasted nice, it was also thin and lacked the concentration I was looking for. Bumping up the ratio solved the issue easily.
Filter Style Mattered
The standard siphon filter is a cloth circle that’s tied securely around a spring-mounted metal disk. When you set it into the top chamber, you pull the spring downwards and latch it to the lower lip of the glass tube to secure the filter in place. Cloth filters are more porous than paper, so more of the coffee’s natural oils can travel thr ough, enhancing the body of a brewed coffee.
The porous nature of a cloth filter also is helpful for allowing water to move up and brewed coffee to move down with ease. The Bodum model I tested came with a plastic disk adorned with multiple, small ridges to serve as the filter. While this let more grit into the bottom chamber, it also choked and clogged during the drawdown, stalling out.
Siphons Needed to Be Sturdy
Aside from the filter mishap with the Bodum model, all of the siphons brewed coffee very similar. What made some models stand out from the rest were small details in design and construction. Because siphon brewing involves moving the brewer on and off of a heat source, a sturdy handle that fits comfortably in your hand is key. And since you have you move the top chamber in and out while also securing it to create a seal, the rubber gasket around the top chamber is also a key design feature. Some gaskets sealed well, but were flimsy enough for the top chamber to be able to lean slightly.
And while every model was made from heatproof borosilicate glass, some models felt thin and brittle while others were thick and sturdy. With stone countertops in my kitchen, I had to stay hyper vigilant every time I moved any siphon around, and the models with thicker glass gave me way more peace of mind.
The Criteria: What to Look for in a Coffee Siphon
A truly great coffee siphon should be made with sturdy glass, have a comfortable handle, and have an easily removable top chamber that also locks in place securely. A good siphon is easy to move from the stovetop to the counter and creates a consistent vacuum draw to filter the coffee, too.
The Best Overall Coffee Siphon: Yama 5-Cup Stovetop Siphon
What we liked: Brewing a siphon on a stovetop can feel dangerous—you have an open flame directly touching a glass vessel, and have to move it off of the heat source while the top chamber is still full of near-boiling water and a coffee slurry. The Yama 5-Cup Stovetop Siphon had a flat base, which both made it feel more secure sitting on a burner and helped it heat up quicker than any other model tested. The handle was also sturdy and comfortable, which made it easy to move the hot siphon from the stove to the counter during the drawdown. The top chamber featured bumps on its rubber collar, helping to lock it in place more firmly than other models.
What we didn’t like: The main drawback with the Yama siphon was the bowl-shaped upper chamber. Because of how wide the chamber was, the coffee grounds spread out pretty far and didn’t immediately saturate as evenly as a more narrow, cylindrical siphon chamber might.
Price at time of publication: $65.
- Filter type: Spring loaded cloth filter
- Time to boil: 5 minutes, 28 seconds
- Heat source: Gas or electric stovetop; not induction compatible
- Care instructions: Hand-wash glass chambers; rinse cloth filter thoroughly between brews; replace filter every 5-10 brew cycles with a siphon cloth filter like these
The Best Electric Coffee Siphon: Klarstein Syphon Vacuum Coffee Maker
What we liked: I was originally skeptical about an electric siphon, but the Klarstein Syphon Vacuum Coffee Maker had solid temperature controls and a simple operation. Once the water in the bottom chamber hit 94ºC (210ºF), the siphon goes into brewing mode, allowing you to set an automatic shutoff based on time. I was surprised at the accuracy of the temperature controls that kept the top chamber from getting too hot, and at how consistent the brew cycle was. For people without a gas or electric burner, the Klarstein siphon performed well in all my tests and was able to brew some tasty coffee with relative ease.
What we didn’t like: The main issue for me is that the heating element takes up the entire bottom of the lower chamber. This means that as soon as the coffee is brewed, it comes in direct contact with the heating element, which could affect the quality of the coffee. I also felt like the materials of the siphon itself felt cheaper than some of the competition, with thinner plastic and a wobbly seal.
Price at time of publish: $90.
- Filter Type: Spring loaded cloth filter
- Time To Boil: 6 minutes, 58 seconds
- Heat Source: Electric base
- Care Instructions: Hand-wash glass chambers; rinse cloth filter thoroughly between brews; replace filter every 5-10 brew cycles with a siphon cloth filter like these
- Hario “Next” Syphon Coffee Maker: The Hario Next felt extremely high-quality, and is modeled after a standard countertop-style siphon. The main issue with a countertop siphon at home is the heat source. While I used to brew countless siphons on a model similar to this one at the coffee bar, home users are limited either to the alcohol wick that comes with it (way too slow, no heat control) or a butane burner, which was tricky to dial in correctly. I had a hard time finding a balance between dialing the burner hot enough to move the water and cool enough to keep the water from overheating. It performed the brew tests just fine, but compared to stovetop models, it’s hard to recommend this model for the average home user.
- Bodum PEBO Siphon Coffee Maker: I was immediately struck by how thin this model's glass was and how flimsy and cheap the handle felt. The Bodum PEBO felt shaky and hard to manage, and its large size was clumsy and awkward to hold. The Bodum PEBO was also the only siphon that didn’t feature the standard spring loaded cloth filter. Instead, it had a plastic filter disk with grooves on the underside that acted as the filtration medium. The main issue with this was that the PEBO stalled out during multiple brews, where the plastic disc cut off flow rate so drastically that the siphon couldn’t finish brewing. Out of all the siphons tested, this is the only model I would recommend people stay far away from.
How do you use a siphon coffee maker?
Coffee siphons function as immersion brewers with an added filter, and uses heated water to create atmospheric pressure to drive water from the bottom chamber to the top. When the heat source is removed, the decreasing pressure creates a vacuum that pulls the brewed coffee back into the bottom chamber.
Does siphon coffee taste better?
Different brew methods might accentuate certain flavor characteristics, but ranking brew methods is one of personal preference. Siphon coffee makers combine immersion brewing with a filter, landing somewhere between a French press and pourover brew method. They also usually use a cloth filter, which can let more of the coffee oils pass through than a paper filter while still filtering out all the solid particles. Some people might appreciate the flavor profile more than other brew methods, but it’s still a matter of personal preference.
How long does it take to make siphon coffee?
It can take up to 10 minutes to brew coffee on a siphon coffee maker. On average, heating water just to the boiling point alone can take five to six minutes, and the total brew process takes around four minutes. The best way to speed up the process is to boil the water separately in an electric kettle first, so that once that water is added to the bottom chamber, you can begin the brewing process sooner.