when to filter

[mlhardesty]

when is beer typically filtered? i know i have read some recent posts that indicate that some people filter between the conditioning tank and serving tank.

my partner and i just brewed our first commercial batch a week ago. fermentation of our ale is complete. we have dish bottom fermenters, so we are thinking about filtering the beer between the fermenter and our bright/conditioning tank.

if we reach terminal gravity in about 6-7 days and then crash the temperature over about 3 days, can we filter into our bright tank and condition for about 3-5 days? if fermentation is complete, would there be any possible issues (such as lack of diacetyl reduction) with filtering prior to conditioning.

thanks.

[RobZamites]

Well, my procedure is to complete fermentation and VDK rests *before* filtering to brights for final conditioning and carbonation. I'm suspecting that filtering would strip out yeast cells which, as I understand (and I'm no brewing school grad), are responsible for diacetyl reduction.
Others much more knowledgable than I will surely chime in and tell me I'm incorrect

Rob

[Larry Horwitz]

Wtf?

Filter when the beer is finished...and it could be argued that at 8 days your beer isn't finished....look for diacetyl in your product. If you find it, age longer.

Filtration is the last step before carbonation and dispense. Beer only conditions when in the presence of yeast. Might I suggest some good brewing books? Brewing: lewis et. al. Kunze text...read up my friend.

[beauxman]

I agree with filtering as the almost last step. The maturation phase occurs (and because of) the presence of (healthy) yeast. 8 days does seem like it is pushing it, especially if you are filtering the beer. You could maybe get away with it in a brewpub with fast moving beer, but packaging?....I would expect a very unstable product that probally changes to the dark side quickly. Your current production fermentation model needs to be re-examined for consistent results. I would be concerned with two (three) things based on what you have posted.

1. Your VDK rest and maturation time is too short.

2. Dish bottom fermentation is fine, but it limits your selection and harvesting of healthy yeast, you will need to refresh your yeast after a few generations...unless you are top cropping.

3. The combination of #1 and #2 make it even worse.

Of course, there are always exceptions and you can push it, but for a good sleep at night not worrying about your yeast and beers?
-Beaux

By the way Rob, you are correct.

[dick murton]

At the end of fermentation, you really need to allow the yeast to settle, and then remove as much sedimented yeast as possible - which is more difficult with dish bottom tanks than conical tanks. This stops the yeast autolysing and producing off flavours. Allow the beer to hold at warm temperature for a period to mop up the diacetyl(butterscotch flavours) - there was a recent discussion all about this, so do a search and you will find lots of info / ideas. Then chill to minus 1 deg C if possible, hold for a period at this temperature, between 24 hours to 42 days but typically 4 days to a week, then filter. Once filtered, the beer will only deteriorate - you need a small amount of yeast to keep it in good nick, and slowly produce the flavour of matured beer.

Cheers