I think that most people will agree that there truly isn’t anything better than a sparkling clear glass of ice cold beer on a hot day. While the quality of some of the mass produced beers there may be called into question, one thing big breweries do well is presenting a brew that is crystal clear.
Commercial breweries accomplish this easily with the aide of fining agents, filtration and pasteurization techniques. The average home-brewer though, often finds beer clarity an issue. For some brewers out there, the frustration of seeking beer clarity may even mean the end of the hobby. But fear not! The solution is far simpler than you could even imagine.
Would you believe the answer to all your clarity problems is seaweed? Okay maybe I got a little ahead of myself there, but the simplest answer to all your homebrew clarity questions is Irish Moss.
What is Irish Moss? Well as you have already guessed, it is not a special type of moss that grows in Ireland. It is in fact a readily harvested blend of seaweed.
Knowing what Irish Moss does is perhaps a much bigger question than just what is Irish Moss. To answer that question, and to single handily solve your beer clarity crisis, we have to have a simple chemistry lesson. Essentially, we need to know what it is that makes your homemade beer cloudy to start with.
There are basically three main sources to cloudiness in beer. These are tannins, excess proteins and yeast. For our purposes I will be focusing on the first two as it relates directly to the wort mash and boil. Just to set your heart at ease though, any cloudiness caused by yeast particles will dissipate as the yeast falls to the bottom of the fermenter over time. More problematic are the excess tannins and proteins suspended in the beer.
Tannins are elements found naturally in the barley grain husk which are released like the sugars during the mashing process. Proteins come from darker grains and non-barley additives like wheat, oats, or flaked barley. Since these tannins and proteins are unsightly and could contribute off flavors to your brew, Irish Moss is used to help remove them.
By simply adding one teaspoon of Irish Moss to five gallons of wort in the last fifteen minutes of the boil, your beer will turn out amazing. Irish Moss is a charged adjunct that pulls tannins and proteins together like a magnet so that the tiny particles form large clumps and sink to the bottom of the brew pot while you cool your wort. Simple as that really!
The other product you have probably heard about is called a whirlfloc tablet. Simply put, a whirlfloc tablet and Irish moss are the exact same thing. The only difference is that the tablet is a bit more concentrated as it can treat up to fifteen gallons, and a bit more convenient as there is no measuring needed.
So to answer the question, what is Irish Moss? Irish Moss is the key to crystal clear beer on a warm sunny day.