Berliner Weisse according to Grenell (part two)

Grenell lists several methods of brewing Berliner Weisse. And I’m going to bore you with all of them.

Here’s the second:

“Method II. - Mash in the medium-milled grist in the kettle with water at 30° R. [37.5º C], at a rate of 3 hectolitres per Zentner [50 kg]. Leave to rest for 1 hour and then raise the temperature to 52° R [65º C] over 40-45 minutes and cover the fire. In the meantime, the mash tun is kept ready, half of the whole mash is drained into it, and the second half of the whole mash, which has been retained in the kettle, is slowly boiled, drained, and filtered as the first wort, as usual it is sparged using a Scottish sparge arm with water at 64-65° [80º - 81.25º C] so that the temperature in the tun does not fall below 60° R [75º C], or even simmeringly hot water, which would give a higher yield. Boil for 1/2 hour and mash out at 61-62° R. [76.25º - 77.5º C]

Hops. Once the bottom of the kettle is covered, 250-325 gr. of light hops are added per Zenter [50 kg] of Malt. - The wort should run off quickly and bright, etc. as in method I.

Pitching temperature. 12° R. [15º C] in cellars below 7° R [8.75º C], also probably at 14-15° R. [17.5º - 18.75º C], that is in summer 9-10° R. [11.25º - 12.5º C] in winter 12-16°R. [15º - 20º C]; Optimum: 10º R. [12.5º C].

It is pitched in large vats, after about eight to twelve hours it is partly transferred to smaller vessels, in which the main fermentation takes its further course, or is used as a "young beer" to blend with beer in the tun.

Yeast pitching rate: 1 litre of thick yeast per Zentner [50 kg] of malt or 5 hectolitres of wort. Length of fermentation: 2.5 to 3 days, also perhaps 3-5 days. After pitching the yeast, remove the head 2-3 times until a pure yeast head appears, then the beer is drawn off (or the yeast head is taken off before drawing off the beer), 1/2 water and 10% fresh beer are added and it is filled into bottles or jugs. Send out after 14 days or you can add up to 1/4 fresh beer, depending on how quickly the Weissbier needs to be delivered.

In the case of bright (sparklingly clear) Weissbier, filtration occurs after the main fermentation, and it is filled into bottles with a very small addition of bottom-fermenting yeast.

Berlin Weisse intended for "external consumption," is stored for some time in cool cellars; where the secondary fermentation proceeds slowly. At the customer, the Weisse is pitched again, for which purpose the brewery sends approximately 80 gr. of yeast per hectolitre. In the pub the landlord also adds 1 kilo of refined sugar, which has previously been dissolved in 3 litres of water,  per hectolitre.

The size of the yeast and sugar addition of course depends on the desired fermentation.”
"Die Fabrikation obergäriger Biere in Praxis und Theorie" by Braumeister Grenell, 1907, pages 70 - 72. (My translation.)

I was at first baffled by the term “scottischer Drehkreuz” in the text. Then twigged that it meant a sparge arm. Another phrase to add to my German brewing vocabulary.

Repitching with bottom-fermenting yeast caught my eye. I’ve heard that some Weizenbier producers do the same for their Hefeweizen. Even though it might be technically illegal – wheat beer has to be top-fermented according to the Reinheitsgebot.

Note that once again the beer is diluted with water at bottling time. This seems to have been a common practice in the brewing of top-fermenting beer in Germany.

The beer intended for "external consumption," – by that I think they mean in pubs – looks like it’s being cask-conditioned in the pub. The addition of extra yeast and sugar would surely have started a secondary fermentation in the cask.