There is such a thing as too much priming sugar in bottles and you should be careful to not commit this mistake, yet it’s not the end of the world if it happens to you.
There is always a way to save your homebrew even if you accidentally put too much priming sugar into the bottles, a keg, or any other container.
What can happen if you put too much priming sugar?
Priming sugar is purposely added prior to bottling as additional food for yeast and its only purpose is to feed the yeast which creates Co2 and thus carbonizes the brew inside the bottle. This is a popular natural method of carbonation, but it’s also possible to force carbonate with a Co2 keg.
Depending on the amount of priming sugar you add, there will be a greater or lesser volume of Co2 in the bottle, and as such, the carbonation will be higher or lower.
Too much priming sugar will result in too high gas volume and it can make the beer overly carbonated which will mask the flavors and cause overwhelming foaming, and in some instances, it may also cause a bottle to explode.
| Co2 Volume | Beer type |
|---|---|
| 1.5-2.0 | Stouts, Porters, Bitter, Brown Ales |
| 2.1-2.6 | Lagers, White Ales, IPA, APA, Cream Ale, Kölsch |
| 2.7-3.0+ | Weizen, Tripel, Saison, Belgian Ales |
The chart mentions some popular styles per standard, yet the rules don’t always have to be followed and if you tweak a recipe a bit you can also change the gas volume.
Most beer bottles can handle up to 4.0 Co2 volume without breaking, but you should be careful not to reach this point as risks can be dangerous.
In comparison, champagne and sparkling wine bottles can handle 5.0-7.0 carb levels and champagnes, and the sparkling vine is usually carbonated at around 4.6 volume.
So, for instance, if you use corn sugar (dextrose) for priming and put in 8.42 oz it will cause a 4.0 volume compared to the desired 2.6 volume which would be achieved with 4.4 oz.
Now you get the point, if you really did put too much it could cause problems, and to see in what range you are use the priming calculator.
If you suspect the bottles could explode, store them in a safe area (ideally a fridge or cold place) where they can’t hurt anyone, and cover them with a blanket or something until you figure out what to do with them.
Don’t dilute it or reprime it
Once you screwed with the priming of your home brew, it’s difficult to go back and the biggest issue is that if you try to fix things by diluting, or letting Co2 escape and repriming it could introduce a whole new set of problems.
These problems are caused by oxidation and trust me it’s better to have overprimed beer than the oxidated one.
This time the batch may not be as you expected it to be but as long as you keep things safe, extra Co2 is not the end of the world.
Oxidation is among the worst enemies of every brewer and oxidation can occur at every step of the brewing process if you are not careful.
It can occur during primary fermentation if the airlock doesn’t do its job, it can happen if the seal on the container is bad, it can happen during racking from one container to another, or during secondary fermentation when adding hops, extra ingredients, or water.
Now, we get to the most sensitive stage, the bottling and this is where the risk of oxidation is the worst.
You’ll inevitably introduce some oxygen into your bottles when you siphon them, prime and put a cap on them. Now, let’s say that your beer is not too oxidated and the effect won’t be noticeable, but remove the cap and let the Co2 out and oxygen in, transfer it from the bottles to another container and dilute it or let it degas and prime it again by repeating the whole process will introduce so much oxygen it won’t be worth it.
This is why I believe that you should not try to save your bottled beer by any of the mentioned methods instead you should use some of the following methods.
Drop the temperature
Temperature either promotes the activity of yeast or slows it down and it can even put yeast into a dormant state where it’s entirely inactive.
As long as the yeast thrives and consumes sugar, the Co2 buildup will continue to grow and the more carbonated the beer will become.
We condition our homebrew at room temperature for the first 10 days or so because, at the warmer temperature, the yeast will consume the sugars the fastest and build that Co2 before we move the brew to the fridge for further conditioning and preserving.
If you cut this initial stage before the yeast has enough time to absorb the sugars, the carbonation levels won’t get that high and you’ll avoid the problem of over-carbonation.
However, if you added ridiculous amounts of priming sugar and the yeast didn’t eat it, it may slightly sweeten the beer, yet this might not be a big issue.
You can let the beer stay for half of the duration at room temperature, so you get normal Co2 volume, and then move it to the fridge.
Ensure the temperature in the fridge is lower than 46.4°F (8°C) or 35.6°F (2°C) as this will make the yeast go dormant and won’t freeze the beer. Yet, if you go below this point you may freeze your beer (28°F or -2°C) which could be bad for the taste once you warm it up again so don’t do it.
Bear in mind that if the yeast is not completely dormant it will still slowly ferment the sugars, but you’ll have probably more than a month to drink the beer before the levels get critical.
(The mentioned applies to any brew brewed with ale yeast but not to lager yeasts, as lager yeasts will continue to ferment at these lower temperatures unless the yeast is dormant, but don’t worry as you’ll still have weeks to drink your beer before all sugars are fermented into Co2 as even lager yeast doesn’t work that fast at low temperatures.)
Pasteurize it
Yeast will start to slowly die at 120°F 49°C, and breweries pasteurize at 140°F as this temperature effectively kills yeast while it doesn’t damage the flavors or impact the beer in any negative way. So, pasteurize your bottles at 140°F for 20-30 minutes.
This way you’ll kill the yeast and it won’t contribute to Co2 volumes any longer. As a result, you’ll save the bottles from exploding or being extraordinarily foamy, but you should time this well.
So, first, let the bottles achieve a desired Co2 volume, open one to test it, and when you think you don’t want it to go further than that, pasteurize them.
The negative side of this is that your homebrew won’t condition nicely and every homebrew needs some time to condition into something delicious. If you cut the conditioning process you may end up with a lower-quality brew but you’ll at least deal with the problem of over-carbonation.
I would only use this method if I brewed some style that is fine with minimum conditioning times, so if the beer is already tasting good and you think you can pasteurize it to deal with the issue of over-carbonation, go ahead!
Do the testing
As with anything else, you can follow the formulas and advice from the people on the internet, but you’ll achieve the most accurate results by making your own tests.
When I prime my homebrew I like to leave the bottles at room temperature for 7 days and then chill one in the fridge for 48 hours before testing it. If the bottle achieved good carbonation levels already or is close to it, I know the rest will be just as good and I might only leave them for a couple more days before I know they are ready.
If overpriming is a problem, you want to be careful not to cause bottle bombs, so it’s important to apply the safety protocol first under which you control the process of carbonation.
For this reason and any other case when you want to monitor carbonation levels, USE A PLASTIC PET BOTTLE.
A single PET bottle is all you need to see when the bottles are ready as the plastics get stiff as the Co2 volume gets high.
Squeeze the bottle prior to filling it with homebrew and priming sugar. In the beginning, the bottle will be super soft. Every few days you’ll be able to notice the squeezed hole disappears and the bottle gets its formal formation, while you know the Co2 build-up is done when the bottle is as thick (or close) to Coke bottles.
The same will occur in your other, glass bottles, so you know when the Co2 is built and you can either quickly fridge it, pasteurize it, or drink it before more Co2 is produced.