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as that can be easily learned by referring to any of the practical brewing tables at the end of this treatise.

As before stated, all we can further do is to wash out from the malt, in the best way we can, whatever extracts may be retained after running off the first tap. There are some who by turning over large quantities of water at very high temperatures, for the raw wort, think, and can, perhaps, show a little more gravity per quarter, as indicated by the saccharometer; but this additional gravity is not saccharine, but mucilage, or some other impurity, which they would be much better without.

TAPS.

Of the produce of Taps, according to the number of Barrels turned on the Malt.

Many erroneous accounts have been given as to the quantity of water, or more properly of wort, retained by the malt, after draining off the first mash as this may be considered a point of some importance to young brewers, as a check or guide for ascertaining that no mistakes have been made in turning on the different quantities of liquor, we shall

here insert our own observations on the subject. The results, however, will vary a little, according to the depth of the malt in the mash-tun, the greater depth producing more extract, and vice versa.

When the first mash is drained off, fine malts will retain about 4 gallons per bushel, or 32 gallons per quarter; inferior malts will retain 4 gallons per bushel, or 36 gallons per quarter, more or less, according to quality, affording a sure guide to ascertain the quantities of liquor which have been used in mashing.

Thus, if brewing 10 quarters of malt we mash with 20 barrels, we should find in the under-back or copper from 10 to 11 barrels, or perhaps, sometimes, a few gallons more of wort, according to the quality of the malt, and its depth in the mash-tun; whatever additional quantity of liquor may be turned on during the first mash, we should find that additional quantity in the worts when collected.

In the after mashings we generally find that the malt will yield a little more than the quantity turned which may on, be easily accounted for by the decrease in the bulk of the malt after every subsequent mashing.

60

OF BOILING.

Various opinions exist as to the boiling of worts. Some think that long boiling, particularly of the second worts, tends to make the beer continue sound. We are not, however, aware of any preservative quality imparted by long boiling; but on the contrary, many injurious effects may be produced by over-boiling, some of which shall be afterwards considered. Long boiling, with free evaporation, undoubtedly adds to the strength of the worts, in proportion to the extent of the evaporation, and thus enables us to make a greater extract from the malt than we could otherwise do, particularly in brewing very strong beers. But where a raw or return wort is taken for next brewing, little or no advantage can be derived therefrom. Mr. Morewood says that at Louvain, in Belgium, which is rather celebrated for its beer, a portion of quick lime is thrown into the worts when boiling,-a very good thing—but soda would be preferable.-Morewood's Inebriating Liquors, page 257.

An erroneous opinion often prevails, that a portion of the saccharine matter of the worts is evaporated along with the steam in boiling. This opinion may have arisen from a mistake in calculating the difference of the extract as shown by the taps, between these taps, and the actual gravity of

the boiled worts in the gyle-tun-or the difference, as some call it, between the raw and boiled gravities. An erroneous method of calculating the extract per quarter is followed by some brewers, who value the gravity of the worts as they flow from the mashtun, instead of taking the gravity of the worts from the coolers as they go into the fermenting tun; thus showing a disparity of from 10 to even 20 per cent. more than the malt actually produces. We shall, however, be able to show, when we afterwards treat of extracts, that both gravities, if properly taken, must be precisely the same, only deducting for the quantity retained by the hops in the different boilings, which is afterwards transferred from one wort to the other in regular progression, so as ultimately to leave in the hops only a very trifling portion of the extract.

There is also a difference of opinion as to the use of open and dome coppers. For fine pale ale, there can be very little doubt that open coppers are preferable, although dome-coppers, (where a free evaporation of steam is allowed without much pressure) can do little harm. It is to be recollected, however, that in proportion to the perpendicular column of worts in the copper, and also to their greater specific gravity, charring will take place. Where, however, a considerable weight must be raised before any steam can escape, as in steamengine boilers, considerable injury may arise, not

only in the boiling of ale worts, but also of porter or stout worts; arising from the following causes.

In the first place, owing to the high pressure of steam, which must necessarily take place before the weight can be raised to allow of its escape, the evaporation of the worts in boiling is so trifling as to prevent the necessary increase of gravity, so as to enable the brewer to turn the proper quantity of liquor over his malt in the mash-tun, for producing the best extracts, particularly for beers of high gravities.

2. The weight to be raised before any escape of steam can take place, and the consequent high pressure, must necessarily raise the temperature of the worts in the copper far above the boiling point. This must, therefore, to a certain extent, alter the component parts of the worts, by charring or carbonising them. That this effect is produced, is sufficiently proved, not only by the brick-red colour of the worts when coming out of the copper, (although brewed from the palest malt,) but also by the beer, which can never have that fine pale or amber colour, so highly desirable for all sorts of ale.

3. The above-mentioned high temperature must also be to a certain extent injurious to brown beer, as it extracts from the hops an astringent bitter, by no means palatable, and to many highly disagreeable. This may not in stout or porter be very perceptible, but in fine ales it is particularly obvious.

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