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Fermcap-s dangerous to use?

I just used fermcap-s on a batch on beer to control the foam from clogging the air-lock. It worked perfectly. While I was doing some more research on the product I saw there was a couple of different forums that were saying the FDA suggests not using silicone-containing antifoam for unfiltered beers. Anyone have any more knowledge on this?



There was a discussion a month or so back. IIRC a Dr. (or so his handle says) chimed in and said there was no issues. Do some more research and make your decision.

Here is that discussion.


Its in GasX. The stuff is a polymer so it will drop out. Doesnt affect beer head and I see that as proof its not carrying through to the beer.

Fermcap S is safe to use. The active ingredient isn’t even absorbed into the body when injested. Like posted earlier, it is the same thing as found in Gas-X, which millions injest directly everyday at higher doses then you would find in your beer.

Technically, Fermcap is supposed to be filtered before the beer is consumed. For me, it’s enough of a concern that I’ve limited my use of Fermcap, but not discontinued it completely.

I don’t add it to the wort to prevent the krausen from getting high, just to the kettle. I figure it will drop with the hot/cold break that way. Any bit of carryover will drop with the yeast/trub after fermentation. I still say the proof of it being gone is that it doesn’t affect beer head.

But is it gone or just used up?

I don’t think its used up or changed chemically in any way. I think the stuff sticks to the head-forming proteins and prevents the formation of a film by lowering surface tension. I believe that it is removed when the hot/cold break forms and it is carried down then. I don’t think its a matter of degrading the chemical to its constituents of carbon and silica. If it didn’t drop out it would keep working to prevent bubbles from forming/staying formed.

I’m with Lennie on this. It decreases that surface tension and prevents foam from forming. If you drop it in the kettle as the foam is just beginning to form you can see it working.

I also don’t use it in the fermenter only in the kettle. Since I have read things about it needing to be be filtered, I also have significantly decreased the amount I use. I find that about 1 drop per 2 gallons in the fermenter is enough to keep the head to a minimum.

I also have not seen any decrease in head formation in the finished beer but the head will drop immediately if you put a drop of this in a finished beer. The fact that it is recommended to filter tells me that the compound is not “used up” or else it would not filter out.

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