Monday, 13 May 2013

How to make Groterjan Porter and Feinbitter-Starkbier (Dörfel part 4)

1962 menu from the Hardtke Weissbier- und
Charlottenburger Pilsner-Stuben in Berlin
F. Feinbitter-Starkbier

Elegantly bitter strong beer, what a nice name. A nice name for a weird beer. The gravity starts at 16º, which is quite a lot, and only goes down a little.

The grist is 3% black malt, 7% caramel malt, 20% “pale” malt and 70% Munich malt.

The hopping is much closer to what we’re used to today, much higher than for the Malzbier. 400g/hl of best quality hops and 300g/hl of caramel colour. Again they mash in cold at 12–15 C and heat it to 52–53 C. There is a half-hour protein rest, then the mash is heated to 75 C. After 40 minutes conversion time they begin to run off the wort. They do a series of small batch sparges, waiting till each is complete before starting the next and fluffing up the mash to make sure to get all the sugar out of the grains.

The hops are put in while the wort is flowing into the kettle. After boiling for an hour and a half, during which the caramel colour is added, the wort is chilled on the Berieselungskühler to 10 C and yeast is pitched (1L to 10hl wort).

The fermentation must be watched carefully. As soon as the wort has dropped 3º in gravity, after about 40–45 hours, it is chilled through a closed chiller to 3 C and pumped into a lagrering tank. After 2–3 days the fermentation has even at that low temperature produced as much CO2 as is desired for the beer. The pressure is 1.2 atmospheres. The beer is then filtered and immediately bottled and pasteurised for three-quarters of an hour at 60–62 C.

The beer still has 12º extract (that’s more than the starting gravity of many modern beers!) and only 1.2–1.4% alcohol. It has an aromatic malty flavour which is complemented by an elegant hop taste. It is a nourishing beer, which has the same grist as the Porter, but due to the low attenuation has a completely different character.

(That's a weird thing to say. I wouldn’t call 70% Munich and 3% black malt a typical Porter grist. Let's see what they were putting in their Porter.)

G. Porter – Strong beer

The grist is 3% black malt, 7% caramel malt, 20% “pale” malt and 70% Munich malt. (What do you know!) and the gravity 18º.

The hopping rate is 500g/hl and 400g/hl of caramel colour are added during the boil. The mash and boil are the same as for Feinbitter-Starkbier (F), except the wort is boiled for two hours and only cooled down to 16 C. Porter yeast from the previous brew is added at a rate of 1 L to every 3hl of wort (quite a lot of yeast then).

Fermentation takes place at 12–14C and they leave it 14–16 days before racking the beer into small aluminium tanks of 18L. (I don’t understand why they used such small vessels. 18L is however almost exactly the same size as a British pin cask.)

As is usual in England no more yeast is added for secondary fermentation. (Perhaps that's why they added so much in the first place).

The beer is kept in the tanks for 5–6 weeks and allowed to carbonate to 1.2 atmospheres, then bottled without filtration and then pasteurised.

Groterjan only ever made small quantities of this beer. It improves in bottle, but it is not possible to keep the extended lagering time common in England due to lack of tank space.

Dörfel notes that English beers are all top-fermented and that English brewers place great importance on the secondary fermentation yeast. Brettanomyces gives the Porter its peculiar aroma and taste. Schönfeld was able to isolate the fermentation yeast and the secondary yeast and use them separately. At the Hochschulbrauerei they use the technique of adding first a pure-culture yeast and then a pure culture of Brettanomyces afterwards.

1 comment:

  1. This is fascinating! Is the feinbitter-starkbier a descendant of mumme? I vaguely remember reading that it had an incredibly high gravity and low alcohol content and wondered how that worked.