Thin brown residue in Bright tank

[Conan]

Hey y'all,

Took over cleaning out the brights after another employee left, and when we opened one of the tanks found that the bottom had what appeared to be small patches of brownish residue. The beer is filtered. Ideas?

[zbrew2k]

Take a sample of it, put it on a microscope slide and look at it under a microscope.

It could be yeast, DE, or Protein, or all three, and possibly something else.

When beer is filtered with DE, and even sparkling clear, there will be some DE present in the beer. A DE filter is not an absolute filter. It is a depth filter.

Do you chill proof your beer prior to filtration? What is the beer temp when you filter? Do you use a trap filter downstream of the filter? Did the beer from that tank taste ok?

Chances are it is nothing to worry about, it sounds pretty normal.

[BAugust]

Cheers!

This one is pretty simple unless there are some additional details you haven't mentioned. This is very common in any tank, but especially bright beer tanks. It is protien. It accumulates over time and should always be inspected for. A little chlorine in your caustic will remove this very easily. Remember that chlorine is potentially dangerous to your stainless steel if it comes into contact with an acidic environment. Evacuate all CO2 and rince completely before introducing acid. You may have to do this chlorinated wash a few times, depending on the build up. You don't want to do a partial job because you will see strings of this protien in your finished beer if you don't completely remove it.

Additionally, this stuff really builds up in your heat exchanger for wort. A periodic cleaning with some chlorinated caustic will do the trick here too. Just don't do it all the time in order to be kind to your stainless surfaces.

Bob August
Majestic Packaging Solutions

https://www.majesticpackaging.com

[dick murton]

As has previously been said - keep CO2 out of the system so the pH is kept high. Corrosion is more likely to take place if the pH drops below 11, so keep the active caustic level high. Typically also keep the chlorine to no more than 150 ppm, and temperature less than 65 deg C. It is worth dropping your chlorinated caustic rinsing the detergent tank, remaking with fresh caustic and cleaning the tank again with straight caustic before rinsing off etc.

If the staining is very extensive / thick, you may need to repeat the chlorinated caustic clean until bright and shiny.

Have fun

Cheers