Page:A Practical Treatise on Brewing (4th ed.).djvu/129

Rh progress in acidification was then put a stop to, by removing the beer to a colder atmosphere.

Skimming is also attended by a considerable waste of beer, as those who practise it well know. It also generally prevents the possibility of keeping the tun-room clean, splashes of yeast lying all over. We have heard many brewers state their want of confidence in themselves to attempt a vigorous fermentation; and at the same time express their astonishment at seeing it gone through successfully. We are led to conclude, therefore, that inexperience and want of confidence have principally led to the adoption of slow fermentations and skimming.

The fretting, or fretful fermentation, proceeds either from using stale or languid yeast. It is often preceded by unsound worts. The first indication is soon after the tun has creamed over. Instead of rising to a curling top, blue patches make their appearance in different parts of the head, and no proper light yeasty change takes place. In about eight or ten hours a sort of undulating motion is apparent all over the top of the Worts, and soon after this the head, which has never been above three or four inches high, begins to drop, and is replaced by large and rather opaque air-bells, which always denote acidity.

There are various ways of making the