Technique: Clarity, Cold-crashing and Gelatin

Hi Homebrewers,

While most of us do not aim for the same goals in our brewing processes as commercial breweries, such as extremely high efficiency, low sundry costs or precise measurements of gravity, alcohol and yeast cell counts, many of us do concern ourselves with doing our best to get our great tasting beers crystal clear.

Certain beers actually benefit from being cloudy (a nice German hefeweizen or Belgian ale springs to mind). Yeast has flavours and aromas ranging from the good (bananas, clove, pears, raisins, freshly baked bread and biscuits) to the bad (beef or chicken soup, fatty acids, rubbery, sulfury) to the downright ugly (rancid fats, cheesy, soapy, pukey and rotten). While all brewers try to avoid the bad and ugly, too much of a good thing is bad. Just that a bit like everything, restraint is key. While there’s heaps of information to talk about the cool tastes and aromas yeast can produce, its a discussion for another post.

Lets me start out by saying, fining isn’t a must. Crystal clear beer is not so important in big ester-driven wheat beers and alike. However, in beers where there is no room for estery-yeast flavours to hide, like clean-tasting malt-driven lagers, fining your beer it can really improve the overall quality of a pint. Actually, unless I specifically want a cloudy beer, I fine.

There are two really easy ways to fine your beer and ciders at home: cold-crashing and by fining agents.

Cold Crashing
Cold crashing, simply put, is taking your finished fermented beer or cider and chilling it down to near freezing and holding it there for a few days. This will put the little yeasties to sleep and they will gradually flocculation out and settle along with the rest of the trub at the bottom of the fermentor or carboy. This will greatly improve the overall clarity of your beer.

Fining Agents
There is a wide range of fining agents on the market. You can go the commercial route (which in most cases will work very well), but it will often set you back anywhere upto a few dollars per batch. There is another cheap and readily available fining product out there – gelatin. Bog standard powdered gelatin. Gelatin works by coagulation with any proteins and yeasty bits and sending them to the bottom. It works well. Very well. And it is really really cheap. The only problem is that being a animal product it isn’t suitable for vegetarians or vegans. Here’s how to use it:

Sprinkle one teaspoon of gelatin over 100mls of cold water in a microwave-safe container. Allow the gelatin to rehydrate for a few minutes.
Gently stir the gelatin in to the water.
Heat the mixture in 15-30 second bursts . The magic temperature you’re shooting for is between 70-75°C. Which will pasteurise the gelatin. Stir the gelatin until dissolved and then tip into your fermentor or kegged beer or cider. This method of fining will work best if the liquid is really cold.

I hope you found these tips handy!
Happy brewing!