Solids count testing after centrifuge

[dleong]

I want to test for the amount of solids present in the beer after the centrifuge and before the filter press to determine how much DE we should be adding to the slurry. Can you give me some advice into how to dive into this further? Maybe what technique to use in order to count the solids in the beer before the filter press? Is it a good rule of thumb of 1 lb of DE per 1 lb of beer solids?

[dick murton]

The trouble is that filtration performance is dependent upon more than simple yeast count, or solids loading of the beer. This is because of the different particle sizes, and ratio of particle sizes, and the presence or absence of other factors such as beta glucans. So to quote from some notes from Filtrox:-

Dose rate is a parameter which is difficult to pre-estimate, since it is highly dependent on the individual beer. However, the brewery's current experience should provide a good guide. Furthermore, a dose which generates a pressure drop gradient of 0.3 to 0.4 bar per hour is usually considered acceptable. A figure of 100 grams per hectolitre (or 0.1 kg/hl) is typical.


We have used a high speed (sorry, I have no idea how many G this generates), or a haze meter (or Coulter counter has been know to be used in research facilities) is used to give a feel for the relative filtration prospects of a beer.

[dleong]

Thanks Dick for your response. We are currently centrifuging our samples to see if there is any residual detectable solids using a densitometer. We have been unable to detect any percentage of solids for our samples. We are testing post centrifuge and post press. So it seems the centrifuge is doing a great job at clarifying the beer on its own and the DE filter plate and frame press is not as necessary. The last experiment I want to do is dry out samples and evaporating any liquid to see if there can be any detectable left over weight.

The trouble is that filtration performance is dependent upon more than simple yeast count, or solids loading of the beer. This is because of the different particle sizes, and ratio of particle sizes, and the presence or absence of other factors such as beta glucans. So to quote from some notes from Filtrox:-

Dose rate is a parameter which is difficult to pre-estimate, since it is highly dependent on the individual beer. However, the brewery's current experience should provide a good guide. Furthermore, a dose which generates a pressure drop gradient of 0.3 to 0.4 bar per hour is usually considered acceptable. A figure of 100 grams per hectolitre (or 0.1 kg/hl) is typical.


We have used a high speed (sorry, I have no idea how many G this generates), or a haze meter (or Coulter counter has been know to be used in research facilities) is used to give a feel for the relative filtration prospects of a beer.