Unlike chips or powder, oak cubes (each one is about a half an inch in diameter) can easily be added and removed from beer or wine, and can be reused. To use, rinse with water and add to fermenter. These are toasted to a medium toast for a crisper oak character. Use 1 to 2 oz. per 5 gallons of beer or wine, leaving the cubes in contact with the beer for at least 20 days (wine for ast least 60 days). French oak has a milder, more vanilla-like flavor than American oak.