Page:A Practical Treatise on Brewing (4th ed.).djvu/120

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FERMENTATION.

worts are sound, and will go on regularly: if, on the contrary, a faintish, disagreeable, sub-acid flavour, arise at any time during the process, we know that acidity or unsoundness has taken place, which should be corrected.

1. The first stage of fermentation commences with a fine white substance like cream, appearing all round the edges of the gyle-tun; this creamy appearance gradually extends over the surface of the fluid in the tun. This we call creamed over, or the first change.

2. The next should be a curly appearance, like the head of a fine cauliflower, which should also extend all over the tun. This, the second change, we denominate the curling or cauliflower head. This cauliflower head should be examined very narrowly, as from its strong and healthy appearance or otherwise, we may pretty nearly judge of the health of the gyle. As above stated, it should have the appearance of a fine cauliflower. If, however, it should assume the appearance of a well curled wig, (we have no better phrase,) having broad flaky curls, it denotes unsoundness. The aroma should now be very perceptible.

3. The curly head should then rise to a light yeasty or rocky head, little more than perhaps from two to three feet high, of a fine brownish white colour if sound. If unsound, it assumes in some parts an ugly bluish-white appearance, which