I fermented and kegged a beer but noticed that the beer was not pouring very clear. It dawned on me that no clarifying agents were used in the boil.

I want to use gelatin to clear the beer, but the beer is already carbonated. Should I decarb the beer, or just add the gelatin?

  • An answer would be nice, but as I am running out of time the people will have to judge cloudy beer. – Atron Seige Sep 30 '15 at 4:26

To answer your question: Yes. You can add gelatin to a carbonated, kegged beer. I've done it before, actually quite a bit. One thing to be cautious of, adding gelatin to a carbonated keg will causing the beer to foam rapidly. If you do it, I suggest pouring the gelatin in with one hand, and having the lid to the keg in the other hand, ready to quickly seal off the keg before it foams over.

It's important to note though, and I welcome others saying otherwise as I'd like to hear their process, but from my experience, when I forget to add kettle finings, gelatin is not sufficient enough to clear the beer by itself. If I let the keg sit several weeks after I fine it, it will pour clear after several pints, but by itself, gelatin, doesn't seem to do as well as when it's used in conjunction to kettle finings like Irish Moss.

That said, it does look remarkably better than no fining at all. I'd recommend making sure the entire keg, top to bottom is near freezing, and perhaps maybe using a bit more gelatin than usual.

Follow-up on your additional questions:

I add approximately half a gelatin packet to a mug filled approximately two-thirds full of warm water, let it rest for a moment to ensure all the gelatin is submerged (if you don't you risk clumps). I then microwave it for about 1 minute to get it up between 160-180°F to kill off any bacteria, then add it directly to the keg. Some people have come back debunking the theory of why boiling gelatin in the water is a bad thing. My process works for me, it's easy and consistent, so I see no need to change it.

Also, yes. You need to ensure your beer is as close to freezing as possible to ensure that chill haze has come into effect, the primary factor that will turn a cold beer cloudy. If you're willing to put in the effort to make sure it's a consistent temperature across the entire keg (I've seen a lot of homemade keggerators where the temperature can be off by quite a bit, 10-15° worth, between the bottom and the top of the keggerator), you can add your gelatin, purge the keg with CO2, then give it a shake to make sure the temperature is even throughout. Don't do this before you add the gelatin though, for the same reasons you don't want to shake a beer can or a soda bottle before opening it.

  • Thanks @Scott. Can you please elaborate on how you prepare the gelatin? – Atron Seige Sep 30 '15 at 5:39
  • I always add Irish moss, but the wort was a gift from a commercial brewery that filter their beer. :) – Atron Seige Sep 30 '15 at 5:39
  • To confirm: get the keg near freezing THEN add the gelatin? – Atron Seige Sep 30 '15 at 5:39
  • Gelatin and Irish moss pull down different haze formers. So that's why when you forget to add the Irish moss the gelatin doesn't seem to work as well. – brewchez Sep 30 '15 at 16:23

You can certainly add it to carbonated beer. I prepare my gelatin in water heated slowly to 150F. Stirring it until its totally dissolved, then letting it sit at room temperature for 5 minutes to be sure the dissolved gelatin has completely hydrated.

Open the keg top and pour it in. Reseal, purge with CO2 quickly and shake it around some to be sure its distributed.

I've never had foaming issues when doing it this way. If you were to put powdered gelatin in then sure it will foam. But I've never had a gushing keg with prepared gelatin.

All that being said, gelatin works best when Irish Moss has used. Irish Moss pulls out many polyphenol precipitated proteins created in the kettle (hot break). Gelatin is good at pulling down yeast and too a lesser extent polyphenol proteins. Gelatin alone has a hard time doing both. And adding more thinking you'll get both can just create a gelatin mess in the keg and clog up the dip tube.

  • What is your "gelatin water"? – Atron Seige Oct 1 '15 at 9:21
  • What are you talking about Atron Seige? Prepare the gelatin in water... that is the "gelatin water". – brewchez Oct 14 '15 at 15:02
  • Sorry @brewchez, that was a very bad question! What I should have asked was: How much gelatin and water do you use to make your gelatin water? And what type of gelatin do you use (sheets, granules or powder)? – Atron Seige Oct 15 '15 at 5:40

A few things:

  • In my experience, carbonated beer always clarifies more quickly than un-carbonated beer. Possibly because
  • Carbonation will reduce the pH of beer. According to this paper, the greatest haze intensity of a beer occurs right around pH 4.3 and haze intensity is directly related to haze-active proteins like gelatin's ability to reduce haze. Below or above this pH, the fining agent should not work as well. If your beer carbonated is closer to this pH than it would be uncarbonated (which I would guess it is) it should actually work better. Yeast flocculation also occurs most efficiently around pH 4.5 (see here).
  • If your beer tastes and smells just as you like it now (especially if it's a hoppy beer, but for many other styles as well) forcibly stripping the gas out so that you can fine it may actually detract from the quality of the finished beer, especially aromatically. Plus it sounds like a hassle.

Basically, I think if everything about the beer aside from the clarity is fine, you should probably just add the gelatin to the beer as it is. I can't think of any reason not to.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.