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i just don't get Irish Moss

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SatanPrinceOfDarkness

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I've used it twice now, and both times I feel like it just makes a mess of things.

The first time I probably used too much. I added a full teaspoon to a partial boil. After the cold crash (<30 minutes in an ice bath) and whirlpooling I still just had a thick miso soup-like substance. I basically had to siphon it all up to get anything.

Second time I used the right amount (full boil), and it still seemed like a mess. A bit of miso soup again, but pretty clear for at least half the siphon. Then it just starts getting thicker. I'd have had to leave at least 2 gallons behind which just seems crazy.

Does anyone know the chemical formula for whatever happens using irish moss? It makes the proteins coagulate, but do they suck up water at the same time? How about sugars? If it's just lowering my water volume I can live with it, but if it's sucking up sugars, that's wasted efficiency.

So, what am I doing wrong?
 
Look up carageenan. That's the active ingredient so to speak. It helps proteins precipitate out of solution. The break material absorbs water but it's not bound to it. It's not pulling sugar out of solution.
 
I've never had this experience with irish moss...I mean, there is always stuff in the bottom of the kettle at the end, but irish moss has never caused any noticeable additional loss for me.

Sorry for what may seem like patronizing questions, I just can't think of what else it could be... What kind of beers are you brewing? (Lots of hops or such things would create more trub). And how well are you cooling your wort before you transfer out of the kettle?
 
I've used it twice now, and both times I feel like it just makes a mess of things.

The first time I probably used too much. I added a full teaspoon to a partial boil. After the cold crash (<30 minutes in an ice bath) and whirlpooling I still just had a thick miso soup-like substance. I basically had to siphon it all up to get anything.

Second time I used the right amount (full boil), and it still seemed like a mess. A bit of miso soup again, but pretty clear for at least half the siphon. Then it just starts getting thicker. I'd have had to leave at least 2 gallons behind which just seems crazy.

Does anyone know the chemical formula for whatever happens using irish moss? It makes the proteins coagulate, but do they suck up water at the same time? How about sugars? If it's just lowering my water volume I can live with it, but if it's sucking up sugars, that's wasted efficiency.

So, what am I doing wrong?

I don't leave anything behind and neither should you. That miso soup is mostly sugar laden water with enough proteins to make it look thick. Pour it all into the fermenter and let the yeast decide what part of it they want. When the ferment is over that miso soup will compact down to a half inch layer in the bottom of the fermenter. You will gain about 1 1/2 gallons of beer and your beer will turn out just as clear.
 
When I use it; I do 10-15 minutes of boil cool for a few minutes then run the wort through a counter flow cooler. I usually leave about a pint behind when using whole hops.

I have not noticed a big difference in final clarity when using Irish Moss or Whirlflock. But I usually use the whole hops as a filter medium. I haven't had a chance to brew in a year or two, whole hops used to be available.
 
I don't leave anything behind and neither should you. That miso soup is mostly sugar laden water with enough proteins to make it look thick. Pour it all into the fermenter and let the yeast decide what part of it they want. When the ferment is over that miso soup will compact down to a half inch layer in the bottom of the fermenter. You will gain about 1 1/2 gallons of beer and your beer will turn out just as clear.

Yeah, this all the way. Dump it all in. Once it precipitates, it is no longer in solution. Leave it all to compact and rack off to bottling bucket or keg.
 
I bag my hops and use Irish Moss. I then pour all but the thickest sludge in the bottom of the pot into the fermenter. At best I leave 12 ounces of sludge in the pot. The thickest trub layer I have had was less than 1/2 inch after it compacts.
 
I don't leave anything behind and neither should you. That miso soup is mostly sugar laden water with enough proteins to make it look thick. Pour it all into the fermenter and let the yeast decide what part of it they want. When the ferment is over that miso soup will compact down to a half inch layer in the bottom of the fermenter. You will gain about 1 1/2 gallons of beer and your beer will turn out just as clear.



thank you ! i've lost so much beer already not doing this !
 
Different finings work different ways. Sometimes just one (irish moss, whirlfoc, gelatin, isinglass, etc) won't do the trick and you need more than one. Unless I'm deliberately brewing a beer where I want protein haze, I use whirfloc in every single beer. Same active ingredient as irish moss, but for whatever reason I find whirfloc more effective. Then depending I may use fermenter finings too

And yes, that "miso soup" is the protein matter starting to drop down out of solution as it chills. There are many ways to deal with it (and some brewers do indeed like to get rid of it). The easiest method, as indicated above, is just dump it all in.

And then if I want super, super clear, I cold crash and hit with gelatin or isinglass post-fermentation. But whirfloc plus gelatin while lagering and then into bottles, and despite being bottle conditioned the beer looks like it's been filtered.
 
I wasn't sure about it either till I read Brulospher's website. He does a split batch experiment using Irish Moss. Google it.


Sent from hell
using Home Brew
 
Unless I am mistaken, Irish Moss works by attracting particles in beer because they have an opposite charge from it. The large mass of particles get heavy and sink (fairly) quickly.

It's not for clearing the boil. In fact, it will make MORE stuff appear in the boil as you are actually adding more stuff to the boil when you put it in there.

Transfer to fermentor as normal and let the stuff attract it's proteins and whatnot.

Also, I do believe that it won't get rid of EVERYTHING. Some particles may not have the proper charge to be attracted to it.
 
I wasn't sure about it either till I read Brulospher's website. He does a split batch experiment using Irish Moss. Google it.


Sent from hell
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I read it, and... I guess he is saying it doesn't do much? It makes the beer clear much faster at the beginning, and five weeks after bottling it was a tiny bit more clear. His tasters like the beer without Irish Moss slightly more than the one with (not statistically significant though). I want to make a clear beer, but this doesn't seem to be the way.
 
I often forget irish moss or whirlfloc. It doesn't always seem to make the beer that much clearer. I think making clear beer is a combination of selecting a well-flocculating yeast, having a brewing process that encourages clearer beer (hot break, cold break) selecting ingredients that don't' add cloudiness (some beers are naturally cloudy) and having enough Calcium to help promote clarity.

Since upping my calcium addition I'm seeing much clearer beers.
 

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