sediment post filtration

[beerbeer95648]

Hey everyone,

We recently filtered 25bbl of pilner that had been in cold conditioning for about 3 weeks in the low 30's. We then let it sit in bright for about a month. When we finally kegged it off and opened the tank there was substantial brown sediment. In addition the beer in keg has a very minor haze. Only small daughter type cells under the microscope, not much else to report microscopy wise....No contamination or oxidation noted...

*No pre treatment
*2 micron impregnated sheets on a velo plate and frame
*Best Pilsner Malt


Thoughts? Protein issue? Filtration issue?

[UnFermentable]

My guess is protein. You could take a sample of the sediment to microscope, checking if it's yeast, but its probably protein based haze. It would be unusual for much yeast to make it through a 2 micron filtration unless they were petite mutants or very young daughter cells. When protein haze is present it is possible that over time the proteins bind together and eventually make large enough particulates that they can drop and settle as a "dust" at the bottom of a tank.

Most beer hazes are caused by the agglomeration of protein and polyphenol materials. Content is usually protein (50-75%) and polyphenol (15-20%) but it is thought the polyphenols are more reactive and may be the cause of the haze formation. To reduce haze, you can adopt methods to reduce the content of either protein or polyphenols early in the process. The other approach is to adsorb the agglomerations after their formation via PVPP, silica gel, or a combination of both, prior to filtration.

[TL Services]

Almost certainly sounds like protein/polyphenol haze complex, forming over time and with cold temperatures. As well as considering treatment post-fermentation, you might also want to look at your copper finings regime to ensure that is effective.

[beerbeer95648]

My thoughts too. Thanks for the advice.