In the late Middle Ages, when the Bavarians in the south of Germany, near the Alps, struggled to improve the quality of their beer, brewers in port cities such as Bremen, Hamburg and Lübeck along the Baltic coast were busy producing a very thick, malty, brownish ale that was suitable for trading in merchant ketches and for sustaining sailors during long ocean voyages. 

The beer they made was called Mumme, so-named after a brewer from the city of Braunschweig (Brunswick) who allegedly made it there for the first time in 1492, the same year Columbus set sail in search of the East Indies and ended up in the New World. The pronunciation of the brew is “moom-muh” (not “mummy). Give the two syllables equal weight and pronounce the “u” as in “foot” instead of “mom.”

Mumme beer from Brunswick quickly became an international trading commodity, sailing from the North Sea ports of Hamburg and Bremen to Great Britain, India and the Netherlands. Mumme is an almost syrupy brew, very nourishing, with an extremely high final gravity — how high, though, is anybody’s guess. Apparently, it remained palatable almost forever. Today, we would probably liken the taste of a medieval Mumme to that of a modern Swiss herb candy, but with a hoppy overtone. Unbeknownst to most beer aficionados, the obscure Mumme is of enormous historical significance, because it was probably the world’s first actual beer “style” that was not brewed with herbs. Mumme was always flavored with hops making it the first post-gruit beer. 

Interestingly, this once-dominant brew of the northern German lowlands has faded almost entirely from the beer scene and few people seem to be interested in reviving it. By the middle of the 18th Century, there were only two Mumme breweries left in Braunschweig, the breweries Nettelbeck and Firma Franz Steger. The latter abandoned production in 1954, while Brauerei H. Nettelbeck KG, still markets a Mumme in the can. 

This product is now a rich, but non-alcoholic, soft drink brewed from barley and hops. It tastes similar to the modern Malta from Mexico. Also, an alcoholic Mumme facsimile — though of uncertain authenticity — is still made in Bremen once a year. It is served only one day a year — the second Friday in February — in the Ratskeller (the city councillors’ pub in the basement of the old city hall).

 Mumme — the first global beer

In its heyday, Mumme made its way on sailing ships around the globe. The brew emerged in part as one of the trading beers of the Hanseatic League, the powerful merchant association that ran virtually all of the trade in Europe from the 13th Century onward until it formally dissolved in 1669. 

At the root of the League was a treaty of mutual protection and commercial cooperation, fashioned in 1241 between the Baltic port city of Lübeck and the North Sea port city of Hamburg, on either side of the Danish Peninsula. These cities set up joint representations in distant places as far as Novgorod, Russia, to deal with the czar, and London, England, to deal with the king. 

Soon thereafter, other German cities joined the alliance, and it gradually evolved into the Hanseatic League, an official organization that eventually grew to comprise some 200 cities, including the North Sea port city of Bremen and such cities further inland as Einbeck, Brunswick, Breslau, Magdeburg, Dortmund and Cologne. The League created, in effect, the first European common market, free of tariffs and artificial trade restrictions. 

It traded in almost any commodity, including wine, oil, grain, leather, cloth, copper, iron, salt and beer. It fought and won its own wars and signed its own peace treaties with foreign governments. One such was the Treaty of Stralsund (1370), which gave it a virtual trade monopoly in all of Scandinavia. Henceforth, no Danish king could be crowned without the League’s approval.

Soon the breweries of Hamburg and Bremen were busy to capacity, producing casks of export Mumme. In addition, wagonloads of ales would rumble down the dusty northern highways on their way to the harbor storehouses of the Hanseatic merchants. Bremen took the early lead in beer exports, sending casks of German ale to the then-known world. 

By the end of the 13th Century, thanks to the skills of Bremer brewers and to the sheer size of the markets of the Hanseatic League, no beer was more popular and plentiful in Europe than that brewed in Bremen. The Hamburgers, too, soon entered the international beer business and, during the 14th Century, started to eclipse their rivals from Bremen. Hamburg emerged as the brewing city of the League. 

By 1376, Hamburg recorded 457 burgher-owned breweries, by 1526 there were 531. Together, they brewed almost 25 million liters per year (more than 6.6 million gallons) and employed almost half the city’s wage earning population. It was within this bustling brewing culture that, by the end of the 15th Century, the Mumme ale style became solidified to represent the glory of northern German brewing — at a time when that other German beer culture, the Bavarian lager culture, was being born at the opposite end of the country.

 Mumme variations

It is not certain from the records how the grain bill of an authentic Mumme ought to be composed. It seems that in some cities, notably in Bremen and Brunswick, Mumme tended to be made mostly or entirely from barley, while in Hamburg and Hanover, among other cities, it tended to be made from a mix of barley and wheat. In the northwestern part of Germany, these medieval ales were called Keutebier. 

Apparently, Keutebiers were hopped, reddish to dark-brown, with an up-front sweetness and a viniferous aftertaste. Keutebier is considered the medieval forerunner of the modern altbier. Perhaps the closest present-day brew to the original Keutebier is Pinkus Alt from the Wesphalian town of Münster. 

The Pinkus brewery, unlike the altbier breweries in and around Düsseldorf, makes its unusual alt from 60% barley malt and 40% wheat malt. Pinkus beers are available in the United States through the import channels of Merchant du Vin.

In Hanover, Mumme-style beers were called Broyhan-Bier or Breyhan Bier. Broyhan beer took its name from a Cord Broyhan, a brewmaster and Hanoverian native, who had left his home town to go apprentice with a Hamburg brewer. There he learned the secrets of Hamburger beer. When he returned home, in 1526, he started his own brewery and made his variation on the Hamburg Mumme theme, a well-hopped, light brown ale, probably mashed from one third wheat and two thirds barley. 

Soon other entrepreneurs jumped on the Broyhan bandwagon and opened up competing breweries. In 1609, the city council of Hanover began to regulate the quality and brewing techniques of the local Broyhan beer. It limited the number of licensed brewer burghers to 317, combined all of them into one guild, and incorporated the guild as a company. This Gilde Brauerei (guild brewery) survived into the current millennium as a stock holders’ company and the oldest enterprise in Hanover. In January 2003, it was acquired by Belgian brewing giant InBev. 

Mumme reconstruction

Northern German medieval beers, not unlike modern German beers, tended to be brewed from wort with a starting gravity of about 1.040 to 1.048 (10 °P to 12 °P). Because Mumme had an apparent attenuation of only about 35–40%, it finished at a relatively high FG of 1.024 to 1.031 (6–7.8 °P). 

In attenuation power, these old northern German yeasts were far inferior to their contemporary Bavarian bottom-fermenting relatives. Because all modern brewing yeasts are bred specifically for high attenuation levels, usually between 60–75%, we must play a few tricks if we want to imitate this unusually malty beer. In the mash, we produce as many unfermentable sugars as possible and we interrupt fermentation by kegging the  the brew a little early (bottling is discouraged, see warning ahead). 

In the mash tun, the Mumme’s low attenuation level calls for plenty of caramel barley malt, perhaps up to 70% of the total grain bill, at a color value of perhaps 40 to 60 ºLovibond. Use a regular pale ale malt for the rest. If you prefer to make a more Bremen-style Mumme, use only caramel barley malt. If you prefer a more Hamburg–style Mumme, or a Broyhan-Bier or Keutebier, replace some of the caramel barley malt with caramel wheat malt.

The starting grain bed temperature should be a relatively high 156 °F (69 °C). This is just 2 °F (1 °C) below the temperature at which beta amylase, the enzyme that produces fermentable sugars is denatured. While beta amylase is very weak at this temperature, alpha amylase, the enzyme that produces unfermentable sugars is very strong. 

Boil the brew as you normally would, for about one hour, to isomerize the hop’s alpha-acids. For hop varieties, you are really free to choose whichever you like, except for Pacific Northwest varieties, because we are making a European brew. Hops, like yeasts, obviously have changed since the Middle Ages, so it is really difficult to be authentic. Subjec-tively, I find that hop varieties with citrus notes, such as Tettnanger, provide the best bittering balance for this rather malty-sweet beer. There is only one bittering addition to this brew, no flavor or aroma hops.

In the yeast department, too, let freedom reign, because in the old days, of course, brewers yeasts were always mixed, not pure, strains. Avoid strains that have a high alcohol tolerance: You want the opposite! Generic European ale yeast such as Wyeast 1338 or White Labs WLP011 are good choices for fermenting this brew.

Warning: We strongly advise against bottling this brew as there is a significant danger of exploding bottles and injury. Kegging with cold storage is the preferred method of packaging this beer, as the keg is a stronger container, and the cold temperature storage will greatly reduce yeast activity and rapid consumption. Purge the built-up CO2 periodically.

Pasteurize — if you must! If you have no other choice than to bottle your Mumme, you must pasteurize your bottles within two days from bottling to kill all living yeast! Two days is sufficient to build up effervescence. 

To pasteurize your Mumme, place as many bottles as will fit into a canning cooker or into your brew kettle. Fill the pot with water to cover all bottles entirely. Heat the water slowly to 145 °F (63 °C) and maintain it at that temperature for 30 minutes to ensure that the beer reaches the same temperature as well. 

Use your thermometer frequently to confirm that the kettle content re-mains at the correct temperature. Re-peat this pasteurization until all bottles have been pasteurized! Leave at least one inch (about 2.5 cm) of head space in the bottle to allow for expansion of the liquid during pasteurizing. Also, filtration before bottling is an extra measure that will help reduce the number of active yeast cells. 

Mumme and extract

Mumme is a difficult beer to make for extract-plus-grain brewers, because there is a relatively high proportion of specialty malts in this recipe and because it is always difficult to predict the contribution to gravity of the steeped grains. Perhaps the best routine for extract-plus-grain brewers is to steep the 4.7 lbs. of specialty grains, coarsely milled or cracked, in three muslin bags, in about two to three gallons of 156 °F (69 °C) water for about one hour, to produce the desired unfermentable sugars and to extract flavor and color. 

Add pale ale liquid malt extract gradually to the kettle, measuring the kettle gravity frequently, until you reach a kettle gravity of approximately 1.043 (10.75 °P). With evaporation losses during the boil this method should result in a green beer with the target of OG 1.048 (12 °P). 

If the steeped grain made no contribution to gravity, the entire grain bill of about 6.7 lbs. (3.025 kg) would require a liquid malt extract substitution of about 5.5 lbs. (2.5 kg) of pale ale liquid malt extract. This should give you some idea as to how much pale ale liquid malt extract you should have on hand for a worst-case scenario.

Authentic Mumme is next to impossible to make for extract-only brewers, because there just is not liquid malt extract on the market with the required high proportion of unfermentable sugars, although Laaglander may come close. Perhaps the best compromise is a 50/50 mix of dark British ale and German Hefeweizen extract as a malt base. 

The resulting brew will be slightly paler than the brew made with mashed or steeped grains.

 Horst Dornbusch writes “Style Profile” in each issue of Brew Your Own. He is also the author of  Bavarian Helles and Altbier (Brewers Publications).