A Comprehensive Guide to Using Siphon Coffee Makers! The Complete Process and Methods for Making Siphon Coffee! Essential Safety Tips to Prevent Siphon Pot Accidents!

Introduction to Siphon Coffee

Although the siphon brewer hasn't become a mainstream coffee method, thanks to its involved operation and lengthy preparation time, plenty of enthusiasts remain deeply fascinated by the process - FrontStreet Coffee among them. After all, purely as a spectacle, it offers an experience with few equals. Siphon coffee also has its own distinctive character. So today FrontStreet Coffee will share how to brew siphon coffee properly.

It's worth noting that because siphon brewing is quite unusual, before using one we need not only to understand its working principle but also to clear up some misconceptions about it, and to recognize and avoid incorrect operation to prevent the risk of a broken pot. Once we're fully familiar with it, we'll find that siphon brewing and pot handling aren't as difficult as imagined - they're actually quite enjoyable. So without further ado, FrontStreet Coffee will first walk you through how the siphon pot works.

Working Principle of the Siphon Pot

Although it's called a siphon pot, it doesn't actually work through a siphon principle but through pressure differences created by thermal expansion and contraction. The structure mainly consists of a stand, a lower pot, and an upper pot. As the image below shows, the stand connects to the lower pot, providing fixation and support; the lower pot holds the liquid and heats it, and is roughly spherical to ensure more even heating; the upper pot is a cylinder extending from a slender tube, with a rubber ring at the tube's contraction point - a very important core component.

The extraction process is quite simple. First, fill the lower pot with water and heat it, then place the upper pot in without sealing it tightly. As the temperature rises, the water expands and turns into water vapor more quickly. Once we seal the upper pot tightly, a vacuum forms in the lower pot. The water vapor compresses the space in the lower pot, forcing the hot water to climb continuously up through the tube under pressure. While the hot water sits in the upper pot, we can add coffee grounds for mixed extraction.

After extraction is complete, we remove the heat source. As the temperature falls, the water vapor in the lower pot contracts and the pressure returns to normal. The coffee liquid in the upper pot then flows back into the lower chamber, while the grounds are held back in the upper pot by the filter. When all the coffee liquid has flowed down, extraction is done. (This is why the siphon pot is called a siphon pot - because of this siphoning action.)

Misconceptions About Siphon Brewing

Because the most conventional approach to siphon coffee waits until the water in the lower pot is frequently producing large bubbles before starting extraction, most people assume the brewing temperature is 100°C. There are actually two misconceptions here. The first is that the extraction temperature for siphon coffee is not really 100°C.

In traditional methods, although the lower pot is heated until it bubbles continuously, the hot water at that point has not yet reached boiling - at most around 96°C, with bubble formation accelerated by the boiling chain. Then, when the hot water moves from the lower pot to the upper pot under pressure, it loses heat owing to the upper pot's material and heat absorption from the surroundings. FrontStreet Coffee measured the hot water arriving in the upper pot and found it to be only around 92-93°C. The second misconception concerns the point at which the pressure difference forms: water does not have to be heated to boiling to produce vapor and generate pressure. Water evaporates at any temperature, though the evaporation is slower when the temperature is lower. If we seal the upper pot before frequent bubbling begins, the hot water will still be pushed up into the upper pot, just more slowly.

This means the extraction temperature for siphon brewing is not fixed. We can decide which water temperature to use based on the set extraction time or the roast level of the coffee. For example, if we want a longer extraction time, or are brewing light-roasted coffee that's harder to extract, we can use a higher temperature; if we're brewing darker roasted beans or want a shorter extraction time, we can let the water temperature be lower. The same logic applies to grind size: longer extraction time, darker roast, coarser grind; shorter extraction time, lighter roast, finer grind. (Note, though, that even the coarsest siphon grind is finer than a pour-over grind.)

Siphon Pot Filtration Tools

Besides the stand, upper pot, and lower pot, the siphon pot contains a small accessory - the filter device connected to the boiling chain. The device can be fitted with different filters to taste: filter paper, flannel filter cloth, or other filters (non-woven fabric). (The boiling chain has several uses, such as helping us observe temperature changes and preventing violent boiling. So at the start, we need to place the upper pot properly.)

In the article "The Difference Between Filter Papers is Greater Than the Difference Between Humans and Chimpanzees," FrontStreet Coffee explained that these material differences not only change the seepage speed but also determine how much oil and how many particles are retained in the coffee liquid. Filter paper has the highest precision, so when we use it the resulting siphon coffee is relatively clean with strong flavor clarity. The downside is that it's too clean, lacking the soul of siphon coffee (according to readers in the comments). So generally, when we make coffee for ourselves and don't mind the trouble, FrontStreet Coffee recommends flannel filter cloth as the filtration tool for siphon coffee. Its drawbacks are that it's expensive and relatively troublesome to clean. Its advantage is that it possesses the soul of siphon coffee - it can retain coffee oils and some particles in the liquid, giving the coffee a richer aroma and fuller body.

Coffee Ground Addition Sequence

There are two ways to add grounds in siphon brewing, divided into "pre-addition" and "post-addition." Pre-addition means adding the grounds to the upper pot before the hot water arrives under pressure, then waiting for the water to rise for extraction; post-addition means adding the grounds after the hot water has fully risen into the upper pot for mixed extraction. (The image below shows post-addition.)

Each has its advantages, but in general FrontStreet Coffee recommends the post-addition method for beginners. It has fewer variables and results in relatively even extraction. With pre-addition, the extraction of the grounds varies with the order in which they contact the water, which can bring more layers but also demands a higher level of understanding from the operator.

Siphon Pot Stirring Methods

When you buy a siphon pot, besides the main body described above, it also comes with a stirring rod. This is because siphon extraction is an immersion method, so stirring comes into play during brewing.

There are many stirring methods - the tapping method, circular stirring, cross stirring, Z-shaped stirring, and even figure-eight stirring. Apart from the tapping method, the others provide relatively strong agitation, which can markedly increase the extraction rate (the exact result depends on stirring force and speed). The tapping method uses taps to push the grounds into the water, primarily to fully saturate them. We can choose among these based on our extraction approach - there's no rule saying you can only use one.

Ancillary Tools for Siphon Brewing

Besides the two tools above, when extracting with a siphon pot we also need to prepare two accessories - cloths and a heat source. We need two cloths in total: one dry and one wet. The dry cloth is used to prevent breakage. Before heating the lower pot, wipe away any moisture on the lower chamber, otherwise the moisture makes the lower pot prone to breaking during heating. The wet cloth is used to control the speed of the coffee liquid's return flow, which we'll discuss later.

There are many choices for a heat source - gas stoves, induction cookers, or alcohol lamps; anything that generates heat will work. Common gas stoves and induction cookers can control heat intensity, with relatively fast and stable temperature rise, though they cost somewhat more. Alcohol lamps cost less but have a smaller, less stable heat source and longer heating times. Either way, they all work. Use whatever you have, though FrontStreet Coffee suggests that with an alcohol lamp it's best to add hot water rather than room-temperature water to the lower pot, otherwise heating takes a very long time. Those are the essential points for siphon brewing. Now FrontStreet Coffee will combine them with a practical demonstration.

Siphon Coffee Brewing Method

Let's first understand the extraction parameters. FrontStreet Coffee will use a fast-paced method this time, paired with a light roast bean - Kenya Assalia. The water temperature will therefore be relatively high, around 92°C, meaning we seal once the lower pot reaches frequent bubbling. Since the extraction time is short - just 60 seconds - and the beans are lightly roasted, we use a grind two degrees finer than pour-over: EK43 setting 9, with 90% passing a #20 sieve. The coffee-to-water ratio is 1:14, meaning 20g of grounds with 280ml of hot water. So first, prepare all the equipment and pour the target amount of water into the lower pot.

After pouring, remember to use the dry cloth to wipe water droplets from the lower pot to avoid the risk of breakage.

After wiping, first install the filter device in the upper pot. Specifically, lower the boiling chain from inside the upper pot, then hook the chain's hook firmly onto the tube. This way the filter device blocks the upper pot's outlet tightly, preventing excess grounds from seeping into the lower pot, and effectively slows the drainage speed.

After installation, place the upper pot on the lower pot, making sure the boiling chain can touch the bottom, then start heating.

When the lower pot starts continuously producing small water droplets, don't rush. Wait until the small droplets turn into large bubbles, then straighten and press the upper pot to create a vacuum in the lower pot. Afterward, wait until all the hot water has run up into the upper pot, and we can begin extraction.

Start timing as you pour in the grounds, then begin the first stir.

The purpose of this stir is to fully saturate the grounds, equivalent to the bloom in pour-over coffee, so we first use the tapping method, tapping all the grounds into the water to ensure even water absorption.

At 25 seconds, we perform a second stir. Its purpose is to accelerate the dissolution of coffee flavor compounds, so here we can use a technique with relatively strong agitation. For example, FrontStreet Coffee uses the Z-shaped method, drawing Z shapes back and forth through the grounds for 10 seconds.

At 50 seconds, we perform the final stir. Its purpose is also to increase the dissolution of coffee substances, but the difference is that, because we're in the final stage of extraction, there aren't many sweet and sour compounds left in the coffee, so we reduce the stirring force. FrontStreet Coffee uses circular stirring here, drawing slow circles. At 55 seconds we can remove the heat source and wait for the coffee liquid to return. If the return flow is very slow, we can speed up the temperature drop by wiping the lower pot with the wet cloth, which accelerates the return and avoids the risk of over-extraction.

When the coffee liquid has fully returned to the lower pot, extraction can end. The siphon coffee we pour out may be a bit hot, so let it cool appropriately before tasting. After letting it sit a while, FrontStreet Coffee tasted it. Besides Kenya's bright cherry tomato and plum sour notes, we also tasted brown sugar and apricot sweetness. The overall body is full and round. Although the layers aren't as distinct as pour-over, siphon coffee does feel more substantial, with a more prominent aroma - a completely different experience.

FrontStreet Coffee Recommendation

Siphon's flannel filter retains oils and fine particles, so it flatters beans with a fuller body and a bright fruit core - exactly the profile of FrontStreet Coffee's Kenya Cherry Tomato. From Kenya's Thika region at 1550-1750 meters, using the classic SL28 and SL34 varieties and a local 72-hour double-washed fermentation, it brings vivid cherry tomato, smoked plum, pear, and black plum notes with a bright, solid acidity and a clean, long brown-sugar-and-green-tea finish. Brewed in a siphon, those bright tomato and plum notes come through clearly, just as in the demonstration above.

If you want to lean into the richer, rounder side that siphon handles so well, choose FrontStreet Coffee's PWN Indonesian Golden Mandheling. Roasted to a medium-dark level, it shows almost no acidity: full-bodied and lingering, it opens with herbal and dark chocolate aroma and a faint earthy note, with clean layers and a sweet, mellow finish. It is a fine everyday cup and an equally good gift.