Clarifying Beer

It's been nearly a month and you've waited patientlywort must be force-cooled to below 50ºF to
for your latest batch of homebrewed beer. The timesecure a satisfactory break, and it precipitates best
has come and you open a bottle or pull the tap andat 32 to 41ºF. A sparkling clear beer can be
begin to fill a glass of what you hope will be yourbrewed by cooling the wort just above freezing until
next favorite beer (generally speaking my favoriteit becomes slushy. This procedure reduces the need
beer is usually the one I'm drinking at the moment).for clarification. A long, slow cooling does not give a
The taste is great but the beer is hazy and not verygood cold break because more protein is trapped in
clear. You know it taste good but it's hard tosuspension producing a finer trub, chill haze, and
convince your friends, who are used to buying andsometimes a sulfur-like aftertaste to the beer.
drinking sparkling clear beer, that the cloudy haze isDuring fermentation several physical changes occur,
alright to drink and really doesn't affect the taste. It'swhich both produce particles, and facilitate their
widely acknowledged that visual appeal is a majorremoval. First is yeast reproduction creating more
factor for most people when drinking a beer. So,yeast cells an a lower pH which facilitates the
how do we clear things up? A variety of clarifyinginteraction of protein and polyphenols to form NMP's.
agents (called finings) and techniques are available toAs the alcohol level increases the viscosity of the
encourage your beer to clear. The term "fining" canbrew is decreased which aids in the sedimentation of
refer both to the process of clarifying beer or to thethe particles. So the longer you can restrain yourself
agents themselves.from tapping into or pouring yourself a cold one the
Aside from infection and the introduction of foreignclearer the beer will be. After fermentation further
particulates into open vessels, beer clarity, or the lacksedimentation occurs during the cooling of the beer
thereof, is caused by yeast cells andprior to serving. Particle removal at this stage can be
non-microbiological particles (NMP's). Sometimes theaugmented by isenglass and auxillary clarifying agents.
yeast is just stubborn and will not settle out of theThe most popular clarifying agent is, no doubt, Irish
beer. Different yeast strains exhibit differentMoss. Irish moss is a type of seaweed gathered
characteristics during flocculation which producealong shores of the north Atlantic, including Ireland
different problems in settlement. But the biggestfrom whence it derived its name. It sometimes is
problems with clarity, since they are more difficult toreferred to as carrageen, the name of its active
remove than yeast, are non-microbiological particles.ingredient. Irish Moss helps coagulate and reduce haze
The term NMP covers protein, usually associated withforming proteins. Recommended usage is 1 teaspoon
polyphenols and other molecules such as lipids,per 5 gallons of beer (wort). Add 15 minutes before
carbohydrates, and/or metal ions. NMP's arethe end of the boil. Whirlfloc is Irish Moss prepared in
produced, and should be removed, during each stagea quick dissolving, highly soluble tablet form. It does
in the brewing process.the same thing as Irish Moss only that it comes in a
If you are an all-grain brewer then the clarity of yourtablet form. Usage is 1 tablet per 5 gallons.
beer is affected by the amount of fine dusty starchIsinglass is a fish-derived additive that's primarily used
and husk particles created during milling. Most ofto help speed up the clarification of cask-conditioned
these particles can be removed during sparging andales, although some beer-makers will use it to reclaim
recirculating the wort through the mash bed prior tobatches that didn't filter properly. When the beer is
run-off. Coagulation of protein occurs during the wortracked into a keg isinglass finings can be added along
boil. A successful boil means a more efficientwith priming sugar and dry hops before the keg is
coagulation of proteins resulting in large flocs whichsealed up for conditioning. Isinglass contains a very
can be more easily removed as well as the removalpure form of collagen. Isinglass involves stabilizing the
of polyphenolic material which reduces chill-haze. Aprotein and when added to beer isinglass acts like a
successful boil is one that begins with a high wort pHlarge open net with positive charges on the surface
with sufficient proteins present. The boil should beof the molecule. These charged sites act like little
around 215ºF for at least one hour. If the boilmagnets and electrostatically bind yeast cells, due to
is not successful then fine flocs are created andthe negative charge of yeast. The pH of beer is
remain suspended in the wort. Clarifying agents duringusually around 4.5 and at this level the collagen begins
the end of the boil can aid in the removal of particlesto precipitate from solution. As the collagen
and help to produce a clear beer.precipitates it falls through beer pulling yeast to the
Wort cooling causes the proteins to interact withbottom of the fermenter. It is also important that
polyphenols to precipitate as cold break. It is essentialyou store and use your finings at a temperature
that the cold break be precipitated as much asrange of 42-55 ºF (6-13 ºC), or they
possible, which is done by rapid wort cooling. Thesimply will not fine your beer correctly.