Charcoal Clearing and Filtration

[drbobcat]

Does anyone have any experience with using activated charcoal to help clear your sake and if so how did you filter it out? The Text Book of Sake’ Brewing (Brewing Society of Japan) implies using powdered activated charcoal mixed into your sake just after pressing and then filtering “with a cloth”. There is also mention of a cartrige filter that looks similar to a water filter with a paper membrane and a charcoal cartrige. It also mentions passing your sake through a box of what I have to assume if granulated activated charcoal.
Any thoughts or ideas would be appreciated!

[squeegeethree]

I've never done it but with what you are describing you might as well pass it through a Brita which is activated carbon.

[KramerOG]

I have never used activated carbon to make sake. You should be able filter out the carbon the same way you filter the sake. For me that means putting the sake in a keg and pushing the sake through a coarse filter and then a fine filter (5 micron,).

[drbobcat]

Sorry for the late reply, but life has been extremely busy lately. I am assuming that you are racking your sake of the sediment before filtering??? Are you using a plate filter or a cannister style? If you are racking off the sediment I would think that you would be able to pass it through a 1 micron filter especially if you are using CO2 to drive rather than gravity. I would love to know. I have been making sake for years but trying to find any information about the roka stage is frustrating. Thanks!

[KramerOG]

I don't rack the sake off the sediment as I am not using any clarifying agents. I rely on filtration to clear up the sake. Typically, - I've only done this twice - I first filter through a 25 um spiral wound canister filter. Then I filter through a 10 or 5 um "regular" canister filter. I use CO2 to push the sake from 1 keg, through the filter and into the receiving keg.

A few notes: spiral wound filters are much looser then regular canister filters even for the same nominal size. They are only appropriate for coarse filtration. My "pressing" technique lets a lot of solids through so I need a coarse filtration before a fine filtration.

I don't see much difference between 10 and 5 um in terms of clarity. My sake has a slight haze.

Filtration usually goes overnight so as to minimize sake lost in the filter canister.

[drbobcat]

Do you have a problem with the filter clogging? I too have a fair amount of solids from pressing. I currently have about 5 gallons “lagering” at 31* to help the solids settle. It looks like about 3 gallons are clear and 2 galloons have a lot of sediment on the bottom. I would love to capture the sake out of the sediment. My homebrew shop suggested running the sake through a cannister filter with an Anvil pump. I just have visions of the filter clogging and running into a mess. What brand of cannister filter do you have and where did you get it. I greatly appreciate the information!

[KramerOG]

Yes the filter does clog. I could have less clogging issues if I could take the clear supernatant first, but the keg takes off the bottom. I nught be able to rig something up in the future, but regardless I'll have clogs. I filter until the filter clogs. I then invert the filterso that the sake drains out of the filter overnight. I then scrape off the kasu abd then filter thru the same cartridge. As I use kegs I don't worry much about exposure to air although some volatiles are lost. Ideally,the next batch will still be fermenting slowly right before I begin filtration.

A pump and filter should work.

The coarse filters are Hydronix 25 um spiral wound filter cartridges. I use Flow-Pro and Purenex melt blow filter cartridges in 10, 5 and 1 um for the fine filter. I don't think the brands are important; type and size are important. My cartridges are 12 inches long.