Brewing Dunkel Weizenbock on the Grainfather

So I’ve finally joined the 21st century. After 15 years of brewing with a cool box mash tun, I’ve taken the plunge and bought a grain pipe system. I went the whole hog and bought a Grainfather G70 V2. The ‘V2’ refers to a redesign just introduced in the last few months. The big difference is that the overflow pipe has been removed. That was particularly attractive to me, as I am usually making German beers, and more often than not pulling decoctions, so not having to negotiate the pipe while doing so seemed like a real bonus. 

The first step: a little R&D

My plan was to brew the most complicated and disaster-prone beer I could think of. If I can do that, I reasoned, I can do anything. Dunkel Weizenbock fits the bill nicely, a big beer, usually over 7%, with a large proportion of (undermodified!) wheat in the grist. My model was Aventinus from Schnieder in Munich. That one comes in at 8.4%, but is beautifully balanced: alcohol warmth, dark malt flavours and the banana phenols in elegant interplay. 

 

My recipe is taken from the excellent Brewing with Wheat by Stan Hieronymus. He says that Aventinus is made with 60% wheat malt and 1% chocolate for colour. I have heard elsewhere that Schnider actually use roasted barley for the colour, to avoid roasty flavours. Hieronymus also says that wheat crystal malt will do the job nicely, but I opted for wheat chocolate, something that probably didn’t exist when Schnieder first formulated their recipe in the early 20th century. Here is a run down of my malt bill, for a 50L brew:

10kg wheat (Weyermann)

4.5kg Maris Otter (British, obviously)

2.5kg Munich II

250g wheat chocolate

The mash schedule was exactly as Hieronymus advises:

Mash in 35°

Acid rest 45°, 10 minutes

Raise to 64°, pull decoction

Return to mash and raise to 71, 20 minutes

77° for mash out

Mash problems - where to start? Actually it all went quite smoothly. Getting the liquor to recirculate though the grain bed proved tricky especially at the start, but I choked off the pump with the upper tap and soon found the right balance.

 Choking the pump to slow the recirculation

 

 

Pulling the decoction

The decoction was very thick, but I’ve found that so long as you stand over it and stir regularly, there is little risk of burning.

And so to the sparge. I read in one Weizenbock recipe that if the sparge lasts more than three hours, you should reheat the sparge water. An ominous sign. In the event, the sparge was slow, but not that slow, perhaps 40 minutes. One advantage of the Grainfather is that most of the water is in the mash, so the amount of sparging required is significantly less. Just as well for this beer.

A 90-minute boil: this is a malt-forward beer, so there is no point in rushing this. Hops: 73g of Hallertauer at 80 mins; 27g at 15 minutes.

One final problem, when I pumped the wort through the counterflow chiller (which works brilliantly, by the way, much faster than my previous immersion chiller, and far less water used) a thick sediment of cold break accumulated on the hop filter. I had to scrape this off as I went along with the mash paddle, but when I came to clean the machine afterwards, there was a similar thick residue beneath. Clearly, this machine isn’t designed for such a viscous, protein-heavy beer, but then, what is?

Fermentation at 17°. About a day after pitching the yeast (Wyeast Weihenstephan) I removed the lids from the fermenters for open fermentation. Those went back on after about a week, at which point I raised the temperature to 23° for diacetyl rest and full fermentation.

I still only managed a final gravity of 1020, where Schnieder apparently finish at 1012 (how do they do that?). Still, the extra body is quite welcome, and doesn’t noticeably detract. Original gravity was 1076 (exactly the same as Aventinus) and so the ABV came in at 7.4%.

That’s plenty, of course, and I’m very pleased with the results. The banana is present without venturing into bubblegum territory. The malt profile is gorgeous, rich but not too roasty. And the alcohol does exactly what it should, it warms without overpowering. In fact, the alcohol is in the background with this beer, a surprise given its sheer quantity.

What would I change next time? Not much. I might drop the bittering hops by about 10g for better balance. I am also considering a second decoction, to increase the malt profile even further. That’s not necessary, of course, and this recipe would probably work without any decoctions at all (though the sparge could get tricky). But the Grainfather G70 V2 is so accommodating for pulling decoctions, it seems a shame not to. Plus, it’s fun! Real hands-on brewing, even on my new, semi-automated system.

Brewing Bog Myrtle Gruit

 

Bog myrtle, aka sweet gale, Myrica gale

(image Pl@ntnet, Creative Commons)

Brewing gruit is a mysterious art, involving lots of speculation and a frustrating amount of trail and error. I have long been interested in bog myrtle (aka sweet gale, Myrica gale) as a brewing ingredient, and this brew was designed to test its properties and to get a handle on the quantities that should go in, and at which points in the process.

Three native plants are commonly associated with gruit as it was brewed in the UK and northern Europe up to around the 16^th century: yarrow, mugwort and bog myrtle. The first two are easily sourced anywhere in the country, but bog myrtle is more difficult to track down. It likes continuously wet conditions and sandy, acidic soil. My source is a place in Dorset. Bog myrtle has a very distinctive smell, and when you know what to smell for, you can just follow your nose. And when you do find it, you’ll always find lots. My experience in brewing with both yarrow and mugwort has been that discretion is always wise. Both plants quickly overpower, and the results are usually acrid and undrinkable. So I approached bog myrtle with similar caution.

The plant is deciduous, but it has a very strange growth cycle. The flowers appear first, on the otherwise bare stems, and the leaves come later. There may be an argument for getting in early in the spring and just taking those flowers, in order to get a higher proportion of aromatic oils to tannin. But at that stage, the flowers are tiny, and it would take a very long time to pick what you need. I picked mine in September and came away with a mix, mostly of leaves, but with plenty of flowers too.

So what to do with it? I found a recipe in Sacred and Herbal Healing Beers: The Secrets of Ancient Fermentation by Stephen Harrod Buhner (Siris: Boulder 1998, 176). 

A simple process then, with the bog myrtle added at the start of the boil and then for dry hopping (after fermentation, I thought, would be wiser than before). The recipe calls for fresh leaves and berries, and mine were already dried, so that was the first problem. 

 

In fact, the water content of the leaves is already very low, so the 4/1 proportions we assume for wet/dry hops probably would not apply. Another question arises about the difference between adding the bog myrtle at the boil and at the dry hop stage. It would seem logical that the boil addition would impart bitterness (or at least tannin astringency) and flavour, while the dry addition would impart aroma. But there is no isomerisation going on here, so the behaviour of hops is of little help. In the end I came up with the following recipe, for a 50L brew.

12.5kg maris otter

Mash temp: 64°

Boil time: 60 minutes

Additions of dried bog myrtle: 80g at 60 minutes; 40g at 30 minutes; 110g dry hop

Yeast: US05

Initial gravity: 1043

Final gravity: 1012

ABV: 4.1%

As I was trying to accentuate the resinous, aromatic qualities of the bog myrtle, I aimed for a dry malt profile, so a 64° mash-in and the dry-finishing US05 yeast. The bog myrtle went in the wort in bags, so as to avoid having to scoop out all the tiny twigs. I tasted and stirred throughout the boil, increasingly frustrated that the bog myrtle flavours did not seem to be coming through, hence the second addition. In retrospect, I needn’t have worried—the quantities here are more than enough. The dry hop addition sat in the fermenters for a good week or so.

The results are very fine. The gruit has a cloudy, orange appearance, which must come from the bog myrtle, as maris otter alone would be lighter and clearer. The nose has a distinctively ‘boggy’ note. It’s that same smell that the plant gives off, sweet and resinous. The flavour is different. It is peppery and has an edge that balances well against the malt sweetness. 

What is that edge? The issue with all gruit brewing is how to substitute the alpha acid of hops with some other flavour that will prevent the drink from excessive sweetness. Tannin clearly plays a role in this, and one of the great dangers of boiling any gruit herbs is the excess of tannin they give off. But there are other things going on here too. There is an acidic edge to the taste, pleasant but wholly distinct from hop bitterness. In my previous experiments with gruit herbs, I have often added bittering hops, on the grounds that the herbs themselves do not have this property. But there was no need here; hops would only have confused the flavour profile.

Next time round? I’m reluctant to admit, but there is a case for lowering the quantities of bog myrtle. Or maybe raising the alcohol level would produce a better balance. One risk there is that a higher level of malt sweetness might tip the balance against the dry, resinous profile. Another possible direction is the addition of further gruit herbs. Perhaps a small addition of dried yarrow flowers at the dry hop stage. I’ll look into this next year and report back.

 

 

 

Visit to the Riegele Brauhaus in Augsburg

 Just on my way home from a typically beery trip to Bavaria. Most of the week was spent at Tegernsee, sampling the legendary beers brewed along the banks of the lake there. The plan had been to fly via Munich, but it turned out the EasyJet to Memmingen was much cheaper. As a result, we had a day to kill in nearby Augsburg, and the tour of the famous Riegele Brauhaus sounded like an attractive proposition.

The brewery has 600 years of history and, remarkably, has been in the same family for 28 generations. The current brewhouse dates from 1911. It is organised as a gravity system, with the successive stages on lower floors. The tour, then, begins four or five floors up and ends several floors underground with the lagering tanks.

 

Ingredients: Riegele brews a wide range of beers, including Wiessbier, a top-fermented Kellerbier, and lots of Pilsner and Helles. The malt comes from Pappenheim – and Riegele is clearly a valuable customer for the maltings there.

 

The malt mill was built by a company in Dresden, now long defunct. Paulaner in Munich have another of the same design, so the two breweries put differences aside when it comes to repair and maintenance, sharing parts and expertise.

 

Copper vessels in the spectacular Jungenstil brew room. It is a step mash for pretty much everything. They do decoction mashing, but only for strong malt-forward Dunkels. No need for the Helles, it seems.

 

The yeast lab. Most breweries in these parts rely on external companies to maintain their yeast strains, but Riegele are proud to do so themselves. That is quite a feat, given the number of different styles they produce.

 

Into the lagering cellars.

 

An astonishing amount of beer down here. There are three floors like this.

 

And so the tasting begins. A proper Zwickel, straight out of the tank, fresh and fruity!

 

The structure of the tour is one hour in the brewhouse followed by two hours tasting. A Brotzeit is laid on – so sausages and a potato salad all round. I went for a Kellerbier: top-fermented, rich and dark, the nearest thing you’ll find round here to an English ale. Then some of the Feines Urhell, again from the tap. They brew a Pilsner too, but Augsburg is a Helles area, so this is the standard beer. It is clean and smooth, but with just enough character to make it moreish.

 

Finally, a superstrong Speziator Hell, 8.5%. This is a Doppelbock, but they have tried to retain the Helles character. So it is as light-bodied as you’re going to get for 8.5%. It’s deceptively drinkable – fortunately it only comes in small bottles!

Double Decoction Brewing for Hefeweizen

This post supplements the video “Hefeweizen Double Decoction Brewday”: https://www.youtube.com/watch?v=drnP5PY8DqY

My bible for all things Hefeweizen has long been the book German Wheat Beer by Eric Warner (Boulder: Brewers Publications, 1992). Warner studied at the Technical University of Munich in Weihenstephan, and then brought his valuable knowledge to the English-speaking world (his volume on Kölsch is also excellent). Warner takes a studiously professional approach to brewing wheat beer, but over the years I’ve found several shortcuts and modifications that can simplify things for the homebrewer.

 

WATER

In his book (pp. 55–56), Warner claims that any water can be used for wheat beer. His argument is that there is huge variation in the hardness of waters in different areas of Germany where wheat beer is brewed, and the chemical composition of the alkalinities is also diverse. I have been taking him at his word on this, and just using our—very hard—tap water. But on comparing my most recent brew with Franziskaner, I’m struck by the zesty, clean edge of the latter. I suspect that purer water is one element of this, creating a cleaner flavour and a more acidic profile. For future brews, I will be using purer water, to see where that takes me.

 

STEPS AND DECOCTIONS

In my experience, the banana and clove flavours (esters and phenols produced by the yeast during fermentation) are easily achieved and can often be excessive. Nevertheless, the first stage of a Hefeweizen mash is traditionally an acid rest around 50°. I have the technology (and patience) to do this, so I always do. Rests around 61° and 71° are appropriate, plus a final mashout around 77°.

Decoctions can be incorporated at several stages in this process, the question is how many, and even if it is worth bothering at all. Warner (p. 58) writes of three advantages of decoction mashing, especially for Hefeweizen:

1) It supplies the yeast with more amino acids

2) It breaks down higher proteins and aids runoff

3) It reduces chill haze

From a practical point of view, that second point is particularly important. Sparging with high proportions of wheat is always difficult, but decoction improves the runoff, and the more decoctions the better it is. Just as importantly, the decoctions change the character of the finished beer. With each decoction, the beer becomes slightly darker, not necessarily a goal with Hefeweizen. The malt profile becomes more intense (which is good) but also more complex and grainy (arguably not so good). My last two beers were both Hefeweizen, the first single decocted, the second double. The single-decocted beer had a simpler, cleaner profile, which I think is more appropriate to the style. The double-decocted was darker and more grainy. I also suspect a hint of tannin on the finish, again not good. So, in sum, I’d recommend single-decoction mashing for Hefeweizen.

 

FERMENTING

Pitch the yeast cold. Warner (pp. 72–3) recounts a Bavarian rule of thumb that the pitch temperature added to the ferment temperature should equal 30°. Interestingly, he doesn’t say why this should be. It may be to avoid diacetyl precursors, i.e., if you ferment warmer, you are encouraging diacetyl production, but if you have anticipated this by reducing the precursors (with cold pitching), you will get away with it. My guess is that the science on this has moved on considerably since the book was published in the early 90s.

An interesting appendix to Warner’s book is titled ‘Some Classic Weissbier Breweries and The Beers that Made Them Famous’. Warner consistently recommends brands that have lower esters and phenols. He is particularly fond of Huber Weisses, saying that this is the preferred drink of the students at Weihenstephan. It is a very smooth type of Hefeweizen, and the banana is finely balanced against the malt profile.

That balance is my aim when brewing Hefeweizen. Fermentation temperatures between the mid-teens and the mid-20s are regularly proposed for Hefeweizen, but I’d suggest staying below 20°. My previous two brews have been at 18° and 19°, and have produced excellent results.

 

YEAST HAZE

The texture and consistency of wheat beer are surprisingly difficult to stabilise. Where Warner advises that decoction mashing reduces chill haze, many would argue that such a haze is exactly what you are looking for. But no, to create the kind of texture you find in commercial Hefeweizen, you must crash and chill the beer, then introduced a new yeast culture at bottling/kegging. In Bavaria, lager yeast is often used, as this does not flocculate as readily, and can be relied on to sit in suspension for the lifetime of the beer.

I’d like to propose a shortcut for homebrewers. Don’t crash or chill the wort. As soon as it hits target gravity, just keg or bottle straight away. There are two possible disadvantages here, but both are surmountable. First, it is important to make sure that you do actually reach a low final gravity. There is a dry edge to the finest Hefeweizens, and you are not going to get that if the beer is too sweet. But don’t leave it on the yeast too long either—daily gravity readings from about day five are in order.

The other problem is that the Hefeweizen yeast tends to drop out of suspension. For bottled beer, the sediment can be roused, maybe don’t add it all though. In kegs it is a bit more tricky. I find that you can give the keg a swirl when the beer starts running too clear. Be vigorous with this, because the sediment can be quite firm. The next glass might look like a pint of milk, but it will be delicious.

One last point about Hefeweizen: drink it cold. Higher alcohol German beers tend to benefit from slightly warmer serving temperatures, but the crisp, clean character of Hefeweizen is best enjoyed colder, around 6°. Then there is the issue of the hangover ... perhaps that is down to those higher proteins that Eric Warner so studiously avoids.