Saturday, 23 October 2010

No, no not more about hop additions

I'm afraid it's true. Even more stuff about hop additions. The sparse comments from you lot tell me I'm on the path of rightteousness here.

I've a passage from one of my other favourite brewing manuals, "The Principles and Practice of Brewing" from 1907. I love terchnical brewing books from this period. Mostly becauise I can still just about follow everything in them. Later 20th century works lose me when they go organic chemistry crazy.

"Addition of the Hops.— Much difference prevails as to the time when the hops should be added to the wort in the copper. Some brewers add them as soon as there is a fair quantity of wort in the pan, others just after the wort begins to boil. Probably the most rational method is to add the first portion after the wort has been boiling for ten minutes or a quarter of an hour. By this time a large amount of proteins have coagulated and been thrown out of solution by the mere action of the heat, and the tannin of the hops is then able to expend its full action upon the portion still remaining in solution; in this way a larger total amount would be precipitated. As the fine delicate aroma of the hop is due to the presence of certain volatile oils, which, to a great extent, are dissipated and lost in the boiling process, it is now customary to add the coarser hops first and the finer ones about twenty minutes or half an hour before turning out, and this modification has much to recommend it. Hops contain various constituents, some of which are much more readily soluble than others, and the presence of both is necessary in the finished beer. But, unfortunately, there are other constituents of a highly undesirable nature also present in hops; these are only brought into solution by prolonged boiling, and, as a consequence, are extracted along with some of the loss soluble constituents, which are of a valuable nature. By adding the hops in two portions at different times, this difficulty is to a certain extent overcome. The first portion added is extracted to the fullest extent, and though the undesirable bodies are for the most part dissolved, yet this long-continued extraction is necessary to secure the solution of the hop resins on which the preservative power of the hops depends. The tannin and the essential oils are also dissolved, but the latter are almost completely lost during the prolonged boil. It is undesirable to have too large a quantity of the hop-resins dissolved in the wort, because they are precipitated in the cooler or in the fermenting vat, and contaminate the yeast. But when a portion of the hops is added at a late stage of the boiling, only small quantities of hop-resin and of the objectionable matters are dissolved, whilst the bulk of the tannin and essential oils is extracted; and as the boiling is now short, these last very valuable constituents are only dissipated to a slight degree. It has even been proposed to add the hops in three portions, the first at the commencement, the second in the middle, and the third near the end of the boil. Naturally, the finest hops will always be added last, since it is the essential oils of these which it is the most desirable to retain. The preservative power of the hops is dependent on the soft resins they contain, and these, on excessive boiling, undergo a chemical change and are converted into bodies of a less soluble nature; hence hops should never be boiled a second time. It is highly probable that the long periods which hops are often boiled at the present time might be shortened with advantage.

When the wort is boiled at twice or three times, or when it is distributed over several coppers, each copper should have its due proportion of hops, calculated on the quantity and respective gravity of the wort of each.

Economy in Hopping.— Among the more recent suggestions for effecting economy in the use of hops, the following may be mentioned:— H. W. Gates (English Pat., 25,774 of 1904) proposes to hop beer in the fermentation vessel by lowering into it a special cylindrical receptacle having perforated walls, filled with raw hops, and pumping the beer from the bottom of the fermentation vessel into the top part of the hop cylinder so that it percolates through the hops. When it is not desirable to pump the fermenting beer, the hops may be packed in a perforated cylinder fitted up so as to serve as a rouser which is stirred about in the beer during fermentation. The hops after being thus extracted are said to be suitable for use in the copper. A. J. Murphy (English Pat., 26,136 of 1904) has also devised an apparatus, consisting of a number of perforated tubes or cylinders arranged in a vertical position between perforated top and bottom plates, and around a central rod, for aerating fermenting liquids and for preparing vegetable and other infusions. This apparatus may be used for hopping beer. For this purpose it is charged with hops and alternately raised and lowered in the liquid."
"The Principles and Practice of Brewing", by Walter J. Sykes and Arthur R. Ling, 1907, pages 522-523.

So Sykes and Ling are in the two additions camp. The first 15 minutes after the start of the boil, the second 20 to 30 minutes before the end. Have you noticed something? No two authors have come up with the same recommendation yet.

Note how, rather than reusing the hops from the first copper in the second, they suggest dividing up the hops based on the gravity of the worts. This is the scheme that Barclay Perkins followed, putting rather more hops in the first copper, where the highest-gravity wort was boiled.

Those two patented devices for hopping beer during fermentation sound weird. I wonder if this was a replacement for or supplement to hopping in the copper? I'm pretty sure neither piece of equipment caught on.


Antony Hayes said...

Have you encountered Randall the Enamel Animal?

Ron Pattinson said...


dave said...

Along with thinking about DFH's Randall (though that is for after the beer has been brewed), H. W. Gates patent seems close to Sierra Nevada's "Hop Torpedo" they use in brewing Torpedo Extra IPA:

David said...

Those inventions sound like a way of reusing late/dry hopping hops later (in a boil).

I wouldn't have thought there would be enough hops involved in dry hopping to be worthwhile - would they be late hops? Would the wort be hot in the FV?