Usually you take 3 parts light wheat malt and 1 part barley malt. From 1 scheffel you make 1 ton (100 quart beer – 117 liter). To 12 Scheffel malt make a pan with 500 quart (590 Liter) extract.60 quart (70 liter) of water is added to the crushed malt. Enough hot water is added that the mash reaches a temperature of 30°R (38C). The first rest is for half an hour, while the mash is resting 500 quart (590 liter) of water are brought to a boil. After that the boiling water is added to the mash and mixed. (If you calculate it would overshoot by quite a bit I think they just heated it to roughly 75°C and added it so the mash would come up to 60-65°C) Now 150 quart (175 liter) of wort is transferred to the boil kettle and 7 pound (3.5 kg) of hops are added (often also a little bit of salt). This is now boiled for 15 minutes. After boiling another 300 quart (350 Liter) of wort are added to the boil kettle and heated till it starts boiling. This boiled wort is promptly added to the mash tun. The mash should now have a temperature of 58-60°R (72,5°C – 75°C), if it didn’t reach that temperature another part of the mash is transfered to the boil kettle and cooked. After that transfered again to the mash tun till the temperature is reached. After that the mash is transfered to the lauter tun. The bottom of the lauter tun is layed out with rye straw which was doused in boiling water. First of all you take the thick part of the mash so that it will not be lifted up. After half an hour rest the zapfen is opened. The hazy is put back in the lauter tun and only the clear wort is transfered to the cool ships. To the murky and the stuff that is left 500 quart (590 liter) of 55° (68°C) hot water will be added. After an hour of lauter rest the second part will be lautered and transfered to coolships. Cold water will be added to the spent grain and lautered again. This liquid will be sold to the poor people as Confent, they add the yeast themself and let it ferment.
For the production 2/3 wheat and 1/3 of barley malt is used. Some breweries use oat husks and mash-in the whole at 30 °R (38°C) in the mash tun. After half an hour the mash will be warmed up to 42 °R (52,5 °C) all the while the mash mixer has to be runing. After twenty minutes rest the temperature will be raised to 52 °R (65 °C). A mash rest is done and the mash mixer is stopped. After that a lauter mash is transfered to the lauter tun (roughly one third of the whole mash) and the other two thirds will be brought to a boil in the mash/boil kettle. Per 50 kg of malt 250g of hops will be added (500 g / 100 kg). After half an hour of cooking the mash out will be done at 60 °R (75°C). After one hour rest the lautering begins. The wort will not be boiled but transfered to the coolship. Enough boiled water will be added so the extract will be 10% (roughly 10 plato). The wort will be cooled to 12-14 °R (15-17,5 °C) and transfered to the pitching vessel. 1 Liter of thick yeast will be added to 50 kg of wort.
A one or two step decoction mash was preffered to the upwards infusion mashing. The decoction gave the beer a more hearty taste, which comes forward even more in the Weissbier than with other beers. All this due to the fact that the wort is not cooked. Today this is still practised.
The grist consists of 1/3 Wheat Malz and 2/3 Barley Malz. Amount is 100 kg per 300 Liter. Hopping rate is 25-30g per 100 Liter directly added at mash in.Different than with other top fermenting beers decoction mashing will be used with the Weissbier. After doughing in at 30°C the mash will be slowly heated to 53-54°C and held there for 1/2 hour. After that it will be heated to 75°C and waited for the sachrification to be complete. Usually this already happened before. Now you transfer 1/3 of the mash into the lautertun and cook the rest that is in the mash tun for 1/2 hour.When combining the two parts (lautering) , 76°C (saccharification) should not be exceeded. Before lautering leave the mash for 40 minutes without additional heating. It is really important that the wort runs cristal clear. Tried and tested methods to achieve that are fly sparging and not messing with the grain in the mash. Only thing that should be done is to rake the top to avoid channeling.For the same reason should the sparge water be applied only gently without swirling up the grain. Apply it without interruption and continously without letting the grain run dry.
Traditional the grain bill of Berliner Weisse is a mixture of barley and wheat malt in a ratio of 1 to 3 or 1 to 4. Mashing is done in a „Dreimaischverfahren”, with a mash-in temperature of 36/38°C. Rests will be hold at 44, 60 and 75°C. In the year 1869 Habich described the following mash-in procedure for the production of Weissbier. The mash-in tepmerature is also 38°C. After that the temperature will be elevated with help of boiling water to 56°C. Then 9% husk free thin mash/wort will be drawn and 1.5 kg hops per 100 kg malt will be added. This is then boiled for 15 minutes. After that another 18-20% of thin mash/wort will be drawn and added to the boil kettle. This is then heated to 100 °C. This wort, which has been boiled with hops is then pumped back to the mash tun. As a result the temperature of the mash rises to 66°C. After the cooking of another partial mash/wort the temperature lies at 75°C. After mashing is complete the wort will be pumped into the lauter-tun and after a 45 minute lauter-rest the wort will be lautered crystal clear and yeast will be pitched.
We basically have two groups here most do a protein rest around 52-56 °C and once a rest at 44°C is mentioned. When we look at the table then we see that this slightly favours the Protease and will result in more medium sized proteins that aid the foam.
We have temperatures 65-66°C which are the typical single infusion temperatures we homebrewers are used to. Middle of the road, getting both amylases. One outlier is the 60°C one from the Methner source which is kind of low considering a mash out at 75°C and no special alpha-amylase rest. What is completely weird is the fact that Groterjan did not mention any saccharification rest at all. I think the key here is that heating at Groterjan was maybe so slow that it took more than an hour to heat the mash from 53 to 75 and therefore converting it completely.
Another common point is the mash out at 75 °C, alpha amylase is barely functioning there but not much will happen at that temperature. What is weird, Groterjan claims that this temperature (75/76 °C) is a sacchrification temperature.
Most of the recipes are doing a small pull to boil the hops for 15-30 minutes. Only one recipe mentions a boil of a considerate part of the mash which introduces more tannins into the beer than just the small ~10% pull. Tannins in Berliner Weisse are not a bad thing in general, the beer is ageing and some added body from them are not frowned upon. But as always you should not overdo it.
Now that we know how it was done in the old days, how to adapt these mashing schemes to modern malts and optimise it.
One of the main problems in brewing a traditional Berliner Weisse is head retention. For that we need to maximise the protein content in the finished wort, especially the long and middle chain proteins. If you have enough the LAB (lactic acid bacteria) especially Lactobacillus brevis are not able to chew through them all and some are left to retain head retention. In the old times they where using a protein rich undermodified malt, which meant the proteins where still in long chains and needed to be brought into solution and broken down and therefore they where doing a protein rest. When using modern malts the protein rest is not needed and even detrimental to head retention. One thing you can do in order to get more long chain proteins into the finished wort is to use a big portion of chit or torrefied wheat in the grist and also try to get wheat with a high percentage of protein. The percentage of protein can vary quite a bit in wheat (10,5-16,5%). About the size of the proteins I had a nice discussion with Jace Marti from August Schell brewing and after that I think the maximising of the protein level in the mash is even more important than the length of the proteins. So if you want you can do a 55°C protein rest but I would not do it. The reason for that is to get more long chain proteins in order to let the Lactobacillus chew a little longer on the proteins. So that after Lactobacillus is finished there are enough Proteins left to ensure head retention. The two other things you should to in order to increase head retention are pre acidifying to a pH of 4.5 and adding a small dose of dry hop before bottling.
So my mashing scheme would be:
- 63°C – 60 minutes
- Decoction with 15 minute boil
- 72°C – 20 minutes
- 78°C – mash out
- 98°C – after lauter to pasteurise