SECTION VII._The Theory and Practice of Brewing

_OF BOILING._

It has been a question, whether boiling is necessary to a wort; but

as hops are of a resinous quality, the whole of their virtues are not

yielded by extraction; decoction or boiling is as needful as the plant

itself, and is, together with extraction and fermentation, productive

of that uniformity of taste in the compound, which constitutes good

beer.

Worts are composed of oils, salts, water, and perhaps some small

portion of earth, from both the malt and hops. Oils are capable of

receiving a degree of heat much superior to salts, and these again

surpass, in this respect, the power of water. Before a wort can be

supposed to have received the whole of the fire it can admit of, such a

degree of heat must arise, as will be in a proportion to the quantity

of the oils, the salts, and the water. When this happens, the wort

may be said to be intimately mixed, and to have but one taste. The

fire, made fiercer, would not increase the heat, or more exactly blend

together the constituent parts; this purpose once obtained, the boiling

of the wort is completed.

It follows from thence, that some worts will boil sooner than others,

receive their heat in a less time, and be saturated with less fire;

but, as it is impossible, and, indeed, unnecessary, to estimate exactly

the quantities of oils, salts, and water contained in each different

wort, it is out of our power previously to fix, for any one, the

degree of heat it is capable of. This renders the thermometer in this

case useless, and obliges us to depend entirely on experiment, and to

observe the signs which accompany the act of ebullition.

Fire, as before has been mentioned, when acting upon bodies, endeavours

to make its way through them in right lines. A wort set to boil, makes

a resistance to the effort of fire, in proportion to the different

parts it is composed of. The watery particles are, it is imagined, the

first, which are saturated with fire, and becoming lighter in this

manner, endeavour to rise above the whole. The salts are next, and last

of all the oils. From this struggle proceeds the noise heard when the

wort first boils, which proves how violently it is agitated, before the

different principles are blended one with another. While this vehement

ebullition lasts, we may be sure that the wort is not intimately mixed,

but when the fire has penetrated and united the different parts, the

noise abates, the wort boils smoother, the steam, instead of clouding

promiscuously as it did at first round the top of the copper, rises

more upright, in consequence of the fire passing freely in direct lines

through the drink, and when the fierceness of it drives any part of

the drink from the body of the wort, the part so separated ascends

perpendicularly. Such are the signs by which we may be satisfied

the first wort, or the strongest part of the extracts, has been so

affected by the fire, as to become nearly of one taste. If, at this

time, it is turned out of the copper, it appears pellucid, and forms no

considerable sediment.

The proper time for the boiling of a wort hitherto has been determined,

without any regard to these circumstances; hence the variety of

opinions on this subject; greater, perhaps, than on any other part

of the process. While some brewers would confine boiling to so short

a space as five minutes, there are others who believe two hours

absolutely requisite. The first allege, that the strength of the

wort is lost by long boiling; but this argument will not hold good

against the experiment of boiling a wort in a still, and examining

the collected steam, which appears little else than mere water. Those

who continue boiling the first wort a long time, do it in order to

be satisfied that the fire has had its due effect, and that the hops

have yielded the whole of their virtue. They judge of this by the

wort curdling, and depositing flakes like snow. If a quantity of this

sediment is collected, it will be found to the taste both sweet and

bitter, and if boiled again in water, the decoction, when cold, will

ferment, and yield a vinous liquor. These flakes, therefore, contain

part of the strength of the wort; they consist of the first and

choicest principles of the malt and hops, and, by their subsiding,

become of little or no use.

It appears, from these circumstances, that boiling a first wort too

short or too long a time, is equally detrimental, that different

worts require different times, and these times can only be fixed by

observation.

The first wort having received, by the assistance of the fire, a

sufficient proportion of bitter from the hops, is separated therefrom.

The hops, being deprived of part of their virtues, are, on the other

hand, enriched with some of the glutinous particles of the malt. They

are afterwards, a second, and sometimes a third time, boiled with the

following extractions, and thereby divested not only of what they had

thus obtained, but also of the remaining part of their preservative

qualities. The thinness and fluidity of these last worts render them

extremely proper for this purpose. Their heat is never so intense

as that of the first, when boiling; for, as they consist of fewer

oils, they are incapable of receiving so great a degree of heat. This

deficiency can only be made up by doubling or tripling the space of

time the first wort boiled, so that what is wanted in the intenseness

of heat, may be supplied from its continuance.

The following table is constructed from observations made according to

the foregoing rules.

A TABLE _shewing the time each wort requires to boil for

the several sorts of beer, in every season_.

Vertical heading--

D: Degrees of heat in the air.

| |_______|________|________|________

| | | | |

| |_______|________|________|________

| | | | |

35° 1 2 4 | 1/2 1 2 | 1/2 | 1/2 | 1 | 2

40 1 2 4 | 1/2 1 2 | 1/2 | 1/2 | 1 | 2

45 1 2 4 | 1/2 1 2 | 1/2 | 1/2 | 1 | 2

50 1 2 4 | 1/2 1 2 | 1/2 | 1/2 | 1 | 2

55 2 4 | 1-1/2 3 | 3/4 | 3/4 | 1 | 2

60 2 4 | 1-1/2 3 | 3/4 | 1 | 1-1/2 | 2

It may, perhaps, be objected, that, by a long boiling of the last

worts, the rough and austere parts of the hops may be extracted, and

give a disagreeable taste to the liquor; but it should be observed,

this only happens, either in beers to be long kept, or in such as are

brewed in very hot weather. In the first case the roughness wears off

by age, and grows into strength, and in the last, it is a check to the

proneness musts have in such seasons to ferment.

One observation more is necessary under this head; most coppers,

especially such as are made in London, and set by proper workmen, waste

or steam away, by boiling, about three or four inches of the contained

liquor, in each hour. The quantity wasted being found on trial, and

knowing how much water the copper holds upon an inch, what is steamed

away by boiling in each brewing, may easily be estimated.