- Today's topic: Learn how to siphon beer from one container to another.
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Of all the steps of brewing beer, I actually think it's siphoning that really trips people up, at least to begin with. It seems so simple — we're just transferring beer from one container to another using a rubber hose. Easy-peasy. But then when theory becomes reality, and you're standing in the kitchen with a bunch of beer and a hose in your hand, it's not nearly so intuitive.
My goal today is to walk you through the basic steps of how to siphon beer — what to do, what to expect, and how to practice — so when it comes time to actually transfer your beer in a few days, you won't be left wondering.
Talk Like a Brewer
Siphoning: A way of moving beer form one container to another (or into bottles) without introducing a lot of oxygen into the system, transferring a lot of sediment, or making a major mess.
Racking: Brewing lingo for moving beer from one container to another to move it off of the sediment in one container.
Trub: The sediment that gathers at the bottom of the fermentation container.
What Does Siphoning Mean?
Siphoning is a way of moving — or "racking," as brewers say — beer from one container to the next without introducing a lot of oxygen into the system, transferring a lot of sediment, or making a major mess. You've maybe heard of people siphoning gas from car tanks into gas cans? The same principle applies here.
How Does a Siphon Work?
A siphon operates based on simple physics: If you create a difference in pressure between two containers, and then you force liquid to flow from one container to the next, the water will continue flowing as long as the pressure remains and there is liquid to pump. It's Bernouille's principle!
That's the physics. In practical, homebrewing terms, you're placing the container full of beer on the counter, and an empty container on a chair or the floor a few feet below. (Or the empty bottles — this is the same technique you'll use when it comes time to bottle.) Run a hose between the two containers with one end submerged in the liquid nearly to the bottom of the first container and the other end opening into the second container. Once you get the liquid flowing, it will keep flowing until the first container is emptied. (In our case, we're using the pull of gravity to force pressure into the system. Science!)
We make this whole process a bit easier by using an auto-siphon or a racking cane. This is a skinny tube of hard plastic with a hooked bit on one end. The auto-siphon goes into the bucket with the liquid and the plastic tubing gets attached to that hooked end. If you have an auto-siphon, all you have to do is pump it once or twice and the liquid will start siphoning right away. If you have a racking cane, getting the siphon started is a bit more complicated — take a look at the step-by-step instructions below.
If you're feeling a little panicked right now, it's OK. Part of the reason why siphoning is tricky is because it's something that few of us have ever done before and because it's really difficult to explain it in words. Read through the step-by-step instructions a few times and flip through the gallery of photos. Also, try some practice siphoning with plain water to get a feel for it before you try doing it with your homebrew. It might take you a few tries to understand how the siphon works and feel comfortable with the steps, but after that, it's a skill you'll have for life (which is handy if you ever need to "borrow" gas out of someone else's gas tank).
Why Do We Need to Siphon?
After reading all this, maybe you're wondering why we need to bother with it at all. Why not just pour the liquid from one container to the next? The biggest reason is that we don't want to introduce too much oxygen into the beer at this stage — which you would do if you poured the beer manually, and which can give your beer some oxidized, sherry-like flavors. Siphoning does introduce a little oxygen (it's pretty unavoidable unless you have a pro brewing system), but far less than if you did it the other way.
Siphoning also reduces the amount of sediment that gets transferred from one container to the next. Solids like used-up yeast, protein particles, and leftover bits of grain will gradually settle down to the bottom of your bucket or jug forming a layer of "trub." Siphoning mostly leaves this trub alone; again, a little will get transferred because it's not a perfect system, but it's much less than if you stirred up the trub while pouring the beer yourself.
And finally, siphoning the beer keeps everything a bit neater and contained, especially when bottling. The beer goes right where you want it to go and there are fewer spills to clean up.
→ Primary vs. Secondary Fermentation: If you are curious about one-stage verses two-stage fermentation, or why bother transferring beer from a primary fermenter into a secondary, read through the next post: Transfer Your Beer from the Primary to the Secondary.
What to Do: Starting a Siphon and Transferring Beer
These general directions apply to both transferring from the primary fermentation bucket to the secondary fermentation jug, and also bottling your beer. Flip through the slideshow above for step-by-step photographs of each step.
What You Need
Jug or other container into which you will siphon
Auto-siphon or racking cane
Siphoning Using an Auto-Siphon
- Assemble the siphon: Place the tip on the auto-siphon or racking cane. Attach the plastic tubing to the hooked end of the auto-siphon. Slip the hose clamp over the open end of the hose and move it a few inches up.
- Sanitize your equipment: Be sure to run sanitizer through your auto-siphon and the tubing to sanitize the insides. Also sanitize the container or bottles that you will be siphoning into.
- Place the container of beer and the empty container (or bottles) a few feet below: I usually place the beer on the counter and the empty container on the seat of a chair. Just make sure the two containers are a few feet apart.
- Remove the lid or stopper from the container full of beer. If you're opening the primary fermentation bucket, you will likely see some floaters and some scum around the waterline — this is normal.
- Insert the auto-siphon into the container of beer: Slide the auto-siphon along the wall of the bucket until it hits the bottom and hold it there with your hand or another clamp so that it stays still and doesn't stir up the trub. If transferring from a jug, position the siphon at an angle as you insert it so that the tip lands near the edge.
- Place the open end of the tubing inside the empty container: If you're siphoning into a jug, wedge the tubing so it stays in the neck of the bottle. If you're siphoning into an open container, like another bucket or a stockpot, just let the tubing rest on the bottom of the container for now.
- Pump the auto-siphon a few times: Use your free hand to pull the auto-siphon partway up and pump it once or twice. This should start the flow of beer through the siphon — the beer should entirely fill the tube without any air bubbles. (This step is doable, but a little tricksy, with just one person; if you can, draft a nearby housemate to help you out until the siphon is started.)
- Siphon until the beer is almost entirely transferred: Once the siphon has started, you just need to keep an eye on everything. As the liquid empties into the new container, try to keep splashing to a minimum. If you can, keep the open end of the tubing submerged an inch or so under the surface of the transferred liquid. Use the hose clamp to control the speed of the siphon.
- Tip the original container toward the end of siphoning (optional): This is a bit controversial, as tipping the container can transfer more of the trub than you might like, but personally, I like to get every last drop that I can. I generally tip the container and continue siphoning until the tube becomes very cloudy — most of the trub is left behind and what has been transferred will quickly settle to the bottom of the new container.
- Finish up: When you've finished siphoning, remove the tubing from the new container. If you've just racked into the secondary, insert the jug's stopper and the air lock. If you've just bottled, proceed with capping the beer.
Siphoning Using a Racking Cane
A racking cane is slightly more low-tech than an auto-siphon, and it requires you to start the siphon yourself. The classic way to do this is to suck on the open end of the tubing until the beer is pulled through, but this is just an invitation to bacteria getting in your beer. The better (though admittedly trickier and less fun) way to do it is to do the following:
- Fill the racking can and tube with water: After you've sanitized the cane and the tube, hold the open end of the tube under a running faucet. (Water is basically sterile, so the risk of contamination is low.) When water flows smoothly out the other end of the racking cane, tightly clamp the tube closed with the hose clamp.
- Slide the racking cane into the container of beer: The water will stay contained in the tubing (mostly!), similar to holding your finger over the end of a plastic straw.
- Insert the open end of the tube into the new container.
- Open the hose clamp: With the siphon in place, open the hose clamp and let the water trapped inside flow out into the new container. This should start the flow of liquid, pulling the beer into the siphon. (There are only a few tablespoons of water in the siphon and it's fine to mix it with the beer, but if you prefer, you can empty the siphon into a cup, close the clamp again once the beer is pulled into the siphon, and then open the clamp to continue siphoning into the new container.)
I can't seem to get the siphon started!
Try moving the container of beer and the empty container a little further apart. You may need to set the full container on a few cookbooks or place the empty container on the floor.
I got the siphon started, but it keeps stopping or slowing.
Try moving the container of beer and the empty container a little further apart. Also, make sure that the auto-siphon (or racking cane) is inserted all the way into the original container until it touches the bottom, and that the tube is no more than an inch or two below the surface of the siphoned liquid in the new container.
I forgot to put the tip on my racking cane!
No worries! It's there to help you avoid transferring trub, but the siphon will still work without it.
I transferred a lot of sediment.
It's not a big deal. This sediment will eventually settle to the bottom of the new container.
There seems to be a lot of liquid left behind in the original container.
You probably could have kept siphoning a little longer, maybe even tipped the container toward the end. This can be a bit of a trade-off, especially with these small 1-gallon batches — siphon as much liquid as possible and be OK with some sediment, or avoid all the sediment but leave some beer behind. You just need to decide which scenario you prefer.
Brew Better Beer: A Companion to Beer School
I love brewing beer so much, I wrote a book about it! Brew Better Beer (May 2015, Ten Speed Press) is a complementary guide to Beer School. Take a look for even more nerdy details about homebrewing, how to brew 5-gallon batches, and plenty of recipes for different beers.
→ Find it: Brew Better Beer by Emma Christensen
With The Kitchn's Beer School, we'll teach you how to brew your own beer at home — and brew it with confidence. In 20 lessons and 7 weekend assignments, we'll get you set up with your own home brewery, walk you through your first brew day, show you how to bottle your beer, and then toast you on your first pint. Ready to brew your first beer? Join us!