Tuesday, 2 November 2010

Bored of hop additions yet?

I'm not. I can't speak for you lot.

While searching for some other books at the weekend, I stumbled across a couple of brewing manuals I'd forgotten about. So out came the hand scanner to capture their views on hop additions.

"For the sake of simplicity, it will be assumed that the quantity of wort necessary to prepare the hundred barrels of beer is boiled in one operation. The quantity and quality of the hops vary according to the class of beer which is being brewed. Suppose that the brewer is using hops at the rate of 3 lbs. per quarter of brewing material. This will amount to 69 lbs. of hops. The quantity is weighed out and placed by the side of the copper, and as soon as the copper is well on the boil the hops are thrown in. Some brewers keep back a small portion and add them to the copper a short time before the boiling is completed. The usual period of boiling is from one and a half to three hours. If the wort is boiled in two lengths the hops are apportioned according to the relative strengths of the two worts.

When the contents of the copper have been sufficiently boiled, the fire is drawn or the steam is shut off, and the hops and wort turned out into the hop back. After standing for a few minutes to allow the hops to settle on the false bottom, the taps of the hop back are opened, and the wort flows, or is pumped to the cooler.

The invert sugar is generally added to the copper shortly before turning out."
"The Brewing Industry" by Julian L. Baker, 1905, pages 134-135.

Baker is another single addition man. Though he's a proponent of waiting until the wort is boiling before adding the hops. And he does acknowledge the occasional use of an aroma addition just before the end of the boil.

We're now going to jump forward about half a century:

Make up the copper within four hours from first setting taps. It is imperative to fix the worts constituents by heat as soon as practicable in order to prevent undesirable changes in the underback or copper before boiling.

Heating destroys the action of diastase, and coagulates the albuminous (protein) matters. The main objects of boiling are to assimilate the flavouring essences of the hops, to secure their preservative properties, and to determine the stability of the worts. To accomplish these objects thoroughly a very strong heat is necessary. The "cooking" of worts can be accomplished only at a temperature of not less than 214° Fahr.t. The copper must be constantly attended during boiling, and armed with an oar the brewer must learn to keep the worts in the copper without calling for dampers and the opening of the furnace door. Boil vigorously and continuously for two hours—two hours and a half if the produce is to be a light gravitv beer, remembering that the violence of the boiling is more important than the time taken, and that lengthy boiling interferes with delicacy. The first half-hour is always a trying time: the worts will kick and bump, and from time to time  the hops will cause a "scummy" resinous froth to accumulate with alarming rapidity. Both the kicking worts and the froth will cause the copper to boil over if neglected for a moment, and many gallons of valuable worts may be lost in a few seconds. The subsequent boiling time is less troublesome: the hops with their soluble extract are by this incorporated in the worts and a regular rolling boil ensues; but even this is treacherous and must be watched. Throw in the remainder of the hops, choice hops for flavour, half an hour before turning out copper. If worts are boiled in two succesive coppers, or lengths, a proportion of the hops should be saved for the second copper, and the spent hops of the first copper returned. The worts of the second copper naturally being very considerably weaker than the first worts, the sugar can with advantage be reserved for this second copper. It is a common practice to suspend Invert cans in the boiling worts, and no objection can be offered if care is exercised to see that the outsides of the cans are clean. A better way is to invert the full cans on a platform over a steam nozzle, which can also be utilised for casks of liquid sugars, turning on the steam as the worts begin to boil. Solid glucose should not be thrown into the copper until the worts are boiling. Some brewers consider it advisable to wait until boiling has settled into its stride before dissolving, as brewing sugars do not need excessive sterilisation. This practice has the merit of easing the bumping during the first half hour.

There is quite an art in stoking the furnace in order to maintain the continuous boil so indispensable for cooking worts. Stoke frequently with small quantities of fuel, always leaving one side red, or blazing: never crowd the fire with black coal."
"Practical Brewing"by W.H. Nithsdale and A.J. Mantonn 1947, pages 59-60.

The authors suggest a similar hopping regime to Baker: most at the start of the boil and a second addition half an hour before the end. And they also recommend returning the first copper hops to the second copper. It seems this was a popular practice. If these manuals are to be believed.

There's still lots more to come. Especially if I really start digging around in the more negelcted corners of my book piles.


Bill said...

"Boil vigorously and continuously for two hours—two hours and a half if the produce is to be a light gravitv beer, remembering that the violence of the boiling is more important than the time taken, and that lengthy boiling interferes with delicacy."

Interesting sentence. I wonder if commercial brewers of today boil for 2 or more hours. In homebrewing 1 hour seems to be the norm. And the threat of boilover seems to limit the violence in my brewing.

Barm said...

Brewers today have it so easy. I thought it mind-boggling enough that 19th century brewers employed blacksmiths to look after the delivery horses, but I'd never realised that old-school brewers also had to be expert at stoking a fire!