Kerry FermCap S is a unique emulsion of dimethylpolysiloxane. It is an extremely effective, surface active agent that prevents foam formation during fermentation by reducing surface tension. Reduced foaming increases fermentation capacity and prevents mess, improves alpha-acid utilization and CO₂ recovery, and prevents hazes due to collapsed foam. Because of the novel behavior of FermCap, it completely adsorbs onto the yeast, vessel walls, and filter media. No FermCap remains in the finished beer.

FermCap S should be stored below 85°F, but should not be allowed to freeze.

Recommended usage: Shake vigorously before use. For 5 gallons, mix 0.2-1.6 grams into wort when it is transferred into the fermentation vessel. If not added before pitching yeast, FermCap should be applied as a spray to the fermenting wort to avoid mixing with the yeast. Higher rates of use or additional doses may be called for if the wort contains large amounts of trub (solids), if the wort is highly viscous, if the fermenting vessel is tall and narrow, if the fermentation temperature is high, or if foam is plentiful or robust for any other reason.