Some ferments are so agressive that they foam-up. An excess amount of foam can even make your fermenter overflow. Malted barley as well as molasses fermentation are prone to extreme foam build-up.
Luckily, there’s an easy solution, though!
This sollution is called “Simethicone” (in North America) or “Infacol” (in Europe). Originally, it is an anti-bloating medicine. It helps babies with stomach cramps.
The way it works is as follows: it allows tiny bubbles of gas to join-up and form bigger bubbles. And the bigger sized bubbles are more easily released. From either your intestines or from your fermentation. If you want to stop your fermentation from foaming, one drop per gallon suffices.