Saturday, 11 December 2010

Pale colour again

I seem to be going off on a pale colour tangent. Hope you don't mind. I see it as the charm of this blog. Occasionally wandering off unexpectedly.

I'll start off with another quote of a quote. This is the "Journal of the Institute of Brewing" summarising an article from a German technical publication:

"The Pale Colour of Beer. (Gambrinus; through Der Bierbrauer, 1900, 473).—The Pilsener beer has stimulated the demand for very pale beers, but a correct imitation of the slight greenish tint of Pilsener beer is a matter of some difficulty. The author has observed this greenish colour in four kinds of beer, namely, the Berlin "white beer," the Scotch export pale ale, the Pilsener and the Gratz beers. The first and fourth are prepared by top fermentation, " the second partly by top and partly by bottom," and the third by bottom fermentation.

In considering the causes of this tint the Berlin white beer may be left out of account, since it is made from unboiled wort and the albuminoids of the wort have no chance of being converted into soluble products affecting the colour.

The Indian pale ale for export is brewed as follows :—68 lb. of best hops are used for 1000 lb. of pale malt; 60 lb. of the hops are digested separately with 108 lb. of water at 75° C., and allowed to infuse. This hop infusion is added to the wort, which is then boiled with 8 lb. of hops. The author suggests that the hop infusion extracts the tannin of the hops, which precipitates the albuminoids of the wort during boiling, and the greenish shade is produced.

The Pilsener beer is treated with so large a proportion of hops, that if these were all boiled with the wort the beer would be unpalatable. The hops are therefore divided into three parts: one-third is boiled with the wort in the usual manner, another third receives only half-an-hour's boiling, and the hot wort is then run through the other third at the time of striking the pan. In this way there is a selective extraction of the tannin from the large quantity of hops, and only a partial extraction of the bitter principles ; the large amount of tannin is therefore available for interacting with the albuminoids to produce the greenish colour. The Gratz beer also receives an excessive proportion of hops, and if they were fresh hops the beer would be undrinkable. But only hops five or six years old are employed; it is well known that the storage of hops for long periods causes a destruction or disappearance of the bitter principles and the essential oil, but the tannin would not be affected.

Hence, in all these cases where the greenish colour is characteristic of the beer, the conditions are such as to favour the utilisation of the tannin of the hops, and to restrict that of the bitter and flavouring principles. It therefore follows that the same effect ought to be obtainable by the artificial addition of tannin to a wort treated with a more moderate proportion of hops. This is in fact the case as regards colour, but the artificial addition of tannin causes disturbances in the albuminoids which serve as yeast nutrients, and the fermentation is not satisfactory."
"Journal of the Institute of Brewing, Volume 7" , 1901, pages 122-123.
That lumps together an odd collection of beers: IPA, Berliner Weisse, Pilsener and Grätzer. Beers whose only connection is their pale colour. I missed the Grätzer reference first time I read it. Another one for my collection. It's the first mention I can remember of it using hops that were 5 or 6 years old.

Lets look at the IPA recipe. 68 lbs of hops for 1000 lbs of malt. That's approximately 3 quarters of malt, so around 22 lbs per quarter. That sounds about right.  Around 5 or 6 lbs a barrel, depending on the gravity of the beer. But did they really infuse most of the hops in hot water before adding them to the boil? I'm not convinced about that.

Now Pilsener. That, they say, had three hop additions: a third at the start of the boil, a third half an hour before the end of the boil and a third right at the end. Looks like one of those modern hop schemas. It looks pretty plausible for a beer as renowned for its hoppiness ad Pilsener.

On to quote number two.

"Personally, I have always considered malt flavour a most important characteristic of first-class ale, both pale and mild, but of late years the increased demand for low gravity pale-coloured ales has greatly reduced the sale of full malt-flavoured ales. Pale malts being in such demand, the maltster is afraid to fire his malt high enough to develop much flavour, and consequently most of the pale ale of the present day lacks the delicate malt flavour which only a fair amount of firing, as distinct from curing, will produce.

The use of a high percentage of thin foreign malts which seldom or never give much flavour, and flaked rice and maize, also accounts largely for this absence of true malt flavour."
"Journal of the Institute of Brewing, Volume 7" , 1901, page 199.

Someone else who wasn't too happy of the impact of the serach for a very pale colour on beer flavour.

I must find that piece in "Zeitschrift für das gesammte Brauwesen" about German rice beer. They were obsessed with a very pale colour as well.


Ed said...

I'm not sure about the green tinge being caused by tannins from the hops. I thought the green tinge you can sometimes see in pale beers came from beta glucans from the malt.

drosinsh said...

Isn't attenuation vital too though, indeed the most important element from the standpoint of malt character?

A number of sources in the 1800's insist on the very pale colour of traditional Burton ale, always reputed as one of the best beers in England. Paleness was no obstacle to its richness.

I agree, indeed initially suggested, that the desirability of paleness was seen by some observers as leading to less taste, but it's all relative..


Gary Gillman said...

I am not adopting a pseudonym, drosinsh, somehow this strange name wrote itself as my name on an early morning comment when my mind was still clouded for some reason, perhaps the six threads I compounded last night put me over the edge.