Do I REALLY Need To Sanitize My Corny Keg?

Whenever my friends ask me about brewing beer and if I like it I always say yes, except for the cleaning and sanitizing part!

Even though sanitizing your equipment is vital for any brewer, we’d all like it a lot more if we didn’t have to do it so much and at every stage of the brewing process.

So, can you get away with not sanitizing your corny keg?

Sanitizing your corny keg is essential as you’re likely to be introducing fermented beer into it then force carbonating. This means that the wort is at risk of bacterial infection. This risk is higher after keg storage. The easiest way to sanitize a keg is with a no-rinse sanitizer such as Star San.

If you are asking this question then you may be at risk of making a huge blunder which could lead to a totally ruined beer, so make sure you read on!

Why do you really need to sanitize a keg?

Let’s face it, homebrewers are paranoid about cleaning and sanitizing their equipment. When you first get into this hobby, you probably think that it’s a little over the top, but in fact, this concern is a very real one.

There are certain pieces of brewing equipment which really don’t have to be sanitized before use, read my following two articles information on these: Do I Need To Sanitize My Brew Kettle Before I Use It? | Do I Need To Sanitize My Wort Chiller Or Not?

However, in most scenarios which I can think of you absolutely need to sanitize your keg if you plan to rack your fermented beer into it. This is basically because, despite the alcohol present in your newly fermented beer, bacteria can still ‘attack’ it.

The same would be true if you were breaking your back and bottling your beer, which I still do for the beer that I want to easily transport and give away to friends.

If you are still researching kegs and want to know more about which type would best suit your home brewery, please have a look at my in-depth article about homebrewing kegs.

What sanitizer to use for kegs

When it comes to sanitizing brewing equipment there are two main contenders to choose from:

Star San


For me personally, I much prefer using a non-rinse sanitizer like Star San just because it cuts down on your workload.

With Star San and some similar products, you only need to have direct contact with the sides of your keg for a matter of seconds. On the other hand, iodine-based sanitizers such as Iodophor, although potent need a longer contact time to kill bacteria.

Also, you have to rinse them off several times in order to reduce the risk of adding any unwanted aroma or taste to your beer.

If you haven’t been using Star San I really recommend you go to your local brew shop and get some, alternatively, you can now buy it on Amazon, see the latest deals here.

Plan your next Beer Creation?

Get your brewing supplies directly from

How to sanitize a keg

Only sanitize your keg after you have thoroughly cleaned it, this is best done just before you sanitize it.

Step 1:

Add around a gallon of clean water to the keg and rinse it out a few times (even after cleaning).

Step 2:

Pour in a gallon of sanitizer. Use about 0.2 oz or 5.91 ml of Star San.

Step 3:

Replace the cap and pressurize the keg to 10 PSI until the cap is sealed.

Step 4:

Once pressurized, shake the keg up to make sure you coat the entire inside of it with your sanitizer.

Step 5:

Before use, drain the keg of the sanitizer through the tap, which you’ll need to install beforehand.

Step 6:

Finally, bleed off the CO2, you’re keg is now sterilized and ready for your beer.

New to homebrewing? Please feel free to read my ultimate guide to brewing beer at home and where to start.

Can you sanitize a keg in advance?

Yes, you can definitely make life easier for yourself and sanitize it before you want to use, ideally just after you finish the last of the beer inside it.

Just go through the same steps as I mentioned above but don’t complete step 6 until the day you want to rack your beer.

By leaving the keg pressurized while storing it, you will be able to keep most forms of bacteria out and minimize the risk to your beer.

Some brewers say you don’t even need to keep sanitizer in the keg, just have a significant enough CO2 blanket to keep all the nasty things out. I would say that if you are using Star San, it doesn’t really matter either way.

However, if you are using something like Iodophor it may be better to rinse it out and make sure there is no fluid in any part of your keg before brew day, and then just leave the keg pressurized until use.

Can you leave Star San in a keg?

Yes, as I said before you can definitely leave both Star San and Iodophor in your keg for several days if not weeks with no issues. Although iodine may stain plastics, it’s fine for metals. Star San will also do no lasting damage to your keg if left inside.

Just make sure that you empty your keg of both Star San or Iodophor before you use it for your beer. Star San is safe to drink, that is clear, but you don’t want to dilute your beer or run out of space with a gallon of sanitizer sitting in the bottom of the keg.

How often should you dismantle your keg?

This is a very subjective question and speaking to lots of homebrewers I’ve always heard different answers. There are those who are in the camp that when the keg kicks you need to break it down and clean it thoroughly, while others merely fill it with water, rinse and fill it with something like PBW. They only dismantle the keg occasionally.

There are even those brewers who have never dismantled their kegs after years of use.

I would personally say that if you are using only one or two kegs and you are a regular brewer, then you need to give those kegs a good clean every 1-3 brews. If you are brewing beers that are higher in alcohol content or produce more sediment, then break the kegs down every time they are kicked.

How to clean a corny keg

There are two main approaches you can take, one is to totally dismantle the keg which you should be doing every so often if you don’t do it every time, and the soak method.

Soaking the keg

As soon after you’ve finished that last glass of tasty beer you should fill your keg up about halfway with boiling water. Add a cleaner such as PBW or an oxygen-based cleaner, Oxyclean is good!

Once the keg is half full, pressurize it until the cap is sealed and allow it to soak for 10 minutes or so. After this time, turn the keg upside down and allow it to soak for another 10 minutes.

After giving the keg a really good shake, you can drain it by forcing the water out of the keg with CO2. After it’s been drained, rinse the keg with some more hot water and then some cold water.

Lastly, turn the keg upside down to dry it. If you are going to use it again and you have some Star San, then forget drying it and just dill it up with a gallon of Star San to get it sanitized.

How to clean & sanitize beer lines

The issue that most homebrewers have that your local pub may not suffer so much from is called beer stone. This is actually a build-up of something called calcium oxalate.

Beer stone can build up on all parts of your kegging equipment, especially in our beer lines.

The best way to clean them is to flush some PBW or other cleanser through them, so when you are cleaning your kegs is an ideal time to clean your beer lines too. Just make sure you clean the keg first, then fill it with hot water and PBW and flush your lines second.

Ideally, for best effects you want to draw the cleanser through your beer lines, then close the faucet and allow the solution to soak into the lines for around 15 minutes. After the keg is empty, flush the lines with clean water, about a gallon or so should be enough to reduce the effects of beer stone.

Phil - BeerCreation

Hey, I'm Phil. I'm passionate about all things beer. I love making it, drinking it and best all, learning about it!

Recent Posts