Filtering Inconsistencies

[mspann]

I am using a 40 X 40 plate and frame filter and when using 3 micron pads have had inconsistent results. I crash and use Biofine 4 days prior to filtration. The issue is sometimes a batch will be bright and clear and sometimes the pads will start letting yeast and other haze particles through part way though filtration. I have experienced this with both Scott and Pall pads and have since gone to 2.5 micron pads which always yield great results. Problem is it is stripping too much of the yeast character from the beer. Any experiences with using identical filters pads and procedures and having vastly different results?

Thanks

Matt

[dick murton]

If you are getting yeast through a depth filter pad, it suggests you are overpressurising the system and forcing stuff through. Yeast is quoted as ranging around 7 micron, but that means freshly budded yeast cells will be somewhat smaller (though in beer of this age they should not be budding still, though may simply not have grown much post budding)

3 or 2.5 micron will not remove small haze particles particularly well, so you are likely to be forcing a lot of protein/tanning haze through as well.

Re identical pads question - yes, but always done to pre filtration treatment / quality.

[mspann]

If you are getting yeast through a depth filter pad, it suggests you are overpressurising the system and forcing stuff through. Yeast is quoted as ranging around 7 micron, but that means freshly budded yeast cells will be somewhat smaller (though in beer of this age they should not be budding still, though may simply not have grown much post budding)

3 or 2.5 micron will not remove small haze particles particularly well, so you are likely to be forcing a lot of protein/tanning haze through as well.

Re identical pads question - yes, but always done to pre filtration treatment / quality.

Thanks for the info and oppionion Dick.

Matt

[TL Services]

Variation/inconsistencies in precoat and/or bodyfeed?