The Coffee Syphon (Vacuum) Brewer

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The Coffee Syphon (Vacuum) Brewer

Post by wosbald » Thu May 22, 2014 12:37 pm


The Coffee Syphon is, quite simply, the enthusiast's brewer. It combines the advantages of the French Press, the Filter Drip and the Percolator into a single, elegant, finicky and (if, as is typical, made of glass) fragile device.

Like the French Press, it is a Full-Immersion Brewer. This means that all of the grounds and all of the water are in contact for the full brewing time.

Also like the French Press, it offers (with rigorous methodology) full control of the brewing variables and, thus, repeatability of the brewing process.

Again like the French Press, it offers that advantage of Full-Immersion brewing which makes over-extraction difficult. NOTE: This advantage can be signifcantly negated through either an excessive agitation of the grounds or through the heat source being kept too high for too long a time (this last of which can cause the water to boil and the coffee to isomerize).

Like the Filter Drip, it is capable of straining the finished coffee to a crystalline clarity (i.e. lacking in suspended and sedimented solids).

Like the Percolator, it produces an excruciatingly hot cup of coffee.

Variables to be Considered
  1. Size of the Brewer
    The most common size of Syphons are the 3-cup (12 oz) and the 5-cup (20 oz) versions. 8-cup (32 oz) is the largest practical size (and which is usually only available in stove-top (not free-standing with alcohol burner) versions. 8-cup sizes can also complicate the draining (or "kick-down") of the coffee by lengthening the contact time due both to increased liquid volume as well as a greater amount of grounds through which the liquid must pass. This time can be lengthened all-the-more when cloth or paper filters, rather than nylon-mesh, metal-mesh, glass plugs or plasticine plugs are used. I recommend any of the above 3 sizes. Any size smaller than 3-cup will tend towards impracticality and any larger than 8-cup will introduce excessive problematics.
  2. Type of Filter Plug
    • Cloth Filter - My filtration medium of choice. Highly recommended.
    • Paper Filter - Excellent, though uncommon and, thus perhaps, unnecessary.
    • Glass Filter Rod - Somewhat fragile and finicky, especially if it does not "lock into place" with a chain-and-hook.
    • Metal Filter - A metal apparatus (such as the Nesco filter) which is designed to mechanically strain the coffee. Durable. Easy to clean and maintain.
    • Plasticine Filter - Durable. Available on the Bodum Santos.
    • Nylon-Mesh Filter - Uncommon and fragile.
    • Metal-Mesh Filter - More durable, common, and replaceable than Nylon-Mesh Filters.
  3. Syphon Styles
    • Stove-Top - Very practical, especially if one has a gas stove-top.
    • Free-Standing - Elegant and somewhat portable.
    • Balance-Type - An archaic style. The "coolness" factor far outweighs the "practicality" factor. No more will be said about this style.

Brewing Variables
  1. Grind Size - This variable is obvious to all coffee lovers, so nothing needs to be said about it. My preference for Syphon Brewers is for a Fine Grind. This is neither a Pulverized nor an Espresso Grind. Instead, its consistency is akin to common Table Salt.
  2. Water Quality - Again, this is a no-brainer. Use clean water. Spring water or filtered water is acceptable. Distilled water, in which 1/4 tsp of salt per 1 gallon of water is dissolved, is an excellent choice.
  3. Agitation/Turbulence - Contrary to the common opinion, excessive agitation of the grounds within the water bath can be very deleterious to the final product. This is true for a couple of reasons:
    • It increases the extraction rate, and thus, the likelihood of overextraction.
    • It increases the extraction rate of starches and oils from the coffee which can greatly slow the drainage of the liquid through the grounds and filter during the Kick-Down.
    • By releasing excess starches and oils into the brewing water, it may increase the rate at which a Cloth-Filter occludes, thus shortening its life-span.
    Suffice it to say that, in my methodology, agitation of the grounds should be kept to a minimum. The use of a cloth filter (among a few others) minimizes the excessive agitation from air bubbles that is common with some types of filter plugs (such as the Glass Filter Rod).
  4. Kick-Down - The phenomenon, after the Extinguishment Time, in which the liquid in the Top Bowl begins to be drawn down into the Bottom Bowl.
  5. Contact (or "Dwell") Time - The total time of the brewing cycle. When using a Fine Grind (and assuming Agitation/Turbulence is kept to an absolute minimum), this will generally be about 3-6 minutes (with this variance being due to the volume being brewed). When the brewing technique is correctly executed, this variance will not appreciably affect the flavor profile of the finished brew.

My Recommendations

Leaving aside the question of vintage, electrical, metallic Syphon Brewers (of which I have one), my recommended setup is a glass brewer of either the 3-cup (12 oz), 5-cup (20 oz) or 8-cup (32 oz) sizes, used in conjunction with the use of a Cloth-Filter plug.

Stovetop brewers are probably the most convenient, but, depending upon one's kitchen setup, a brewer designed for use with an alcohol burner may be the best choice. Brewers made by the Yama company are currently the most accessible on the American market. Yama-made stovetop brewers are available in the 5-cup and 8-cup sizes whilst their free-standing alcohol-burner models are available in 3-cup and 5-cup versions.

Use and Care of a Cloth Filter

Before use, the Cloth-Filter must be tied onto the specially-designed, metallic Cloth-Filter Plug.

NOTE: It is helpful, though not absolutely necessary, to soak the Cloth-Filter in boiled water for a few minutes to soften the cloth, allowing it to be more easily stretched to a taut snugness on the plug before the securing strings are decisively tied.

The Cloth-Filter will have two sides: a smooth side that is destined for contact with the coffee grounds and a "furry" side onto which the drawstring is stitched. Place the furry-side of the filter over the metal filter plug while tightening the drawstring. Keep adjusting the filter tauter and tauter whilst tightening the drawstring until a drum-like tautness is achieved. Of course, take care not to overextend this process so as snap the drawstring. Ensure that the filter is taut enough such that the fit is smooth along the circumferential edge of the filter with no "folds" of cloth to interfere with a uniformly tight seal of the filter plug against the surface upon which it rests. This will not only increase the agitation of the brew with the release of large air bubbles, but may also allow some grains of ground coffee to seep into the finished brew.

Once the filter is secured to the plug, it is never to be removed from said plug until it is time to replace the filter with a fresh one. One can discount any advice to tie the filter cloth loosely such that it can be removed from the plug in order to be washed, scrubbed, oxy-cleaned or otherwise manhandled. With a Cloth-Filter, the less that one fusses with it, the better. Simply "set it and forget it", as the saying goes. After each use, the most that one should do to the filter is to gently rinse it under cold, running tap-water and brush off (with one's fingertips) any remaining grains of adhered coffee.

To care for the filter in-between uses, simply submerge the entire assembly in a container of cold water in the fridge. A few drops of liquid bleach can be added to the water each time it is changed (every week or two) so as to keep the water fresh. The filter should never be allowed to dry out as this will cause the coffee oils to oxidize and rancidify. Occasionally (every 20-50 brews, perhaps?), the Cloth-Filter can be cleaned by running the brewer through two or three Water-Only cycles (i.e. without coffee grounds).

Carefully maintained with a hands-off approach, a cloth filter can last for several hundred uses (6 months or more, even with multiple daily uses). Pay little attention to internet advice regarding the frequent changing of Cloth-Filters. (I've even seen an internet recommendation to change it after eight uses!) Properly maintained, such a quick filter change-out is unnecessary as flavor-carryover from brew-to-brew is negligible. It also nullifies the durability-advantage and the economic advantage of Cloth-Filters, which are both a bit pricey (about $8-$10 for a pack of 5) as well as a bit difficult to conveniently source at retail outlets.

Adapting to the Changing Characteristics of a Cloth-Filter

Over time, Cloth-Filters become progressively more occluded with oils. This is unavoidable. Thus, the liquid will continue to drain at a progressively slower rate as the filter is increasingly used. In the practical order, this means little beyond keeping track of the Contact Time over the "long haul". When, as the months go by, the Contact Time becomes unreasonably long (which affects both the flavor and the temperature of the final brew), then it is a signal that a replacing of the filter may be in order.

The Process

NOTE: One will need a smallish dowel, whether of wood, plastic or some other material. Obviously, metal dowels should not be used on glass Syphon Brewers.
  1. Boil the Brewing Water in a Kettle.
  2. Add the Boiled Water to the Bottom Bowl.
  3. Apply the Heat Source to the Bottom Bowl.
  4. Loosely place the Top Bowl (with the Filter Plug attached) into the neck of the Bottom Bowl. Do NOT complete the seal.
  5. When the Water comes to a boil, affix the Top Bowl by completing the seal.
  6. Lower the Heat somewhat (if possible), as the Water rises into the Top Bowl.
  7. Adjust the Heat again, if necessary (and possible), so that it is High enough to maintain the Water in the Top Bowl but Low enough to minimize Agitation/Turbulence.
  8. Add the Finely Ground Coffee and Begin Timing. NOTE: Do not allow the water to sit in the Top Bowl for too long a duration before adding the coffee, as the water temp may infelicitously decrease over time. This is particularly the case if the heat source under the Bottom Bowl is suitably lowered.
  9. Working in concentric circles, quickly, but gently (i.e. without creating undue Agitation), poke the dry grounds with the dowel. They will turn dark as they become wetted. Avoid leaving dry lumps ("islands") of coffee grounds.
  10. Continue the above-noted process of poking the crust with the dowel. One may stop the process once the crust of grounds have fully saturated and sunk beneath the surface.
  11. Extinguish the heat at a time appropriate to obtaining a Contact Time which falls roughly within the 3-6 minute parameter.
  12. When the Brewing Water is fully drawn into the Bottom Bowl, there will be a lot of bubbling and agitation in the Bottom Bowl caused by ambient air bubbles being drawn into it.
  13. When the bubbling in the Bottom Bowl lessens or abates, gently break the seal and remove the Top Bowl.
  14. Coffee is served. Decant coffee into a preheated thermal carafe, if desired.


This should be done immediately after the Brewing process is completed. At the very least, the Cloth-Filter should be immediately cleaned and stored in cold water.
  1. Add cold tap-water to the Top Bowl, gently swish the water and carefully (fragile glass!) invert the bowl over a strainer/fine-mesh colander in the sink in order to contain the grounds. Repeat if necessary.
  2. Under running tap-water, use your hand to loosen and remove any adhering dry grounds in the Top Bowl.
  3. Invert the Top Bowl under the stream of water from the faucet. This entails running cold tap-water "reversely" through the Cloth-Filter by forcing the water through the tip of the Top Bowl's Tube. This will loosen adhered grounds from the Cloth-Filter.
  4. Upright the Top Bowl and run cold tap-water onto the Cloth-Filter to clear away loosened grounds.
  5. Repeat Steps 3 and 4 a few times.
  6. Unfasten the Filter Plug and rinse away any remaining grounds from it. If needed, gently use your hand to brush off the last of the grounds. Do NOT use a brush or anything abrasive.
  7. Store the Cloth-Filter Plug in the container of cold water and place it into the refrigerator.
  8. Finish rinsing out the Top and Bottom Bowls. If cleaned soon after the brewing process is completed, these do not have to be intensively cleaned; a simple rinse (along with a paper towel to wipe away coffee oils in the Top Bowl) will be all that is necessary.
  9. Voilà!
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Re: The Coffee Syphon (Vacuum) Brewer

Post by Jocose » Wed May 18, 2016 4:25 pm

How does Yuban taste in it?
"And for Freds sake, DO NOT point anyone towards CPS or you'll put them off of both Christianity and pipe smoking forever." ~ FredS


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