It's About the Yeast

All About Beer Magazine - Volume 32, Issue 3
July 1, 2011 By K. Florian Klemp

What a great time to be a brewer. From progressive and avant-garde beers to the authentic, Old-World stalwarts, we can savor them all. And in many ways, we can thank the homebrewers, whose ranks nourished, inspired and galvanized the microbrewery movement and continue to do so today.

As a style writer, I am fascinated by the historical perspective of brewing, particularly the evolution of beer styles. They materialized from a distinctly regional cocktail of necessity, agriculture, climate, geology, available technology and knowledge. As a homebrewer, I am often interested in reproducing these classics, not only for the challenge, but also because they are deliciously diverse and surprisingly simple. Some have been stylistically finalized in fairly recent times, but others are remnants of centuries-old brewing, so interwoven into their culture and beloved in their region that it would be ludicrous to imagine their demise. The wheat beers of Bavaria are perfect examples of those: a venerable family of beers that has gallantly taken on all comers and persevered, remained relatively true to their roots, and are righteously as popular as ever.

The three most common styles, hefeweizen/weissbier/weisse (blonde to deep gold), dunkelweizen (copper to amber) and weizenbock (amber to brown), serve up a spectrum of personality, straightforward recipe formulation, low-maintenance brewing and just enough wiggle room to personalize. Extract brewers have just as much sway over their recipes as their all-grain brethren with the availability of high quality, wheat-heavy extracts.

Hefeweizen and dunkelweizen can be brewed and consumed rather quickly for a natural and refreshing year-round quaff, while the stronger weizenbock can withstand some aging, to be enjoyed during the cool months. These wheat beers are purely ingredient-driven and somewhat forgiving, with essential yeasty contributions and rustic, hazy charm.

In Central Europe, there was a time when wheat beer was as common as barley beer. In fact, beer was often distinguished by color and referred to as either white beer (wheat) or red/brown beer (barley). The wheat was raw in many cases, eliminating harsh flavors and acrid darkening imparted by open fires used for the kilning of barley malt. The Reinheitsgebot Purity Law mandated the use of malted wheat, with a measure of at least 50 percent of the grist. This separated the Bavarian wheat beers from the others, shaping the styles we know today. In Germany, wheat beer was reserved for royalty in the south (modern weizen), and preferred by Germany’s best brewers in Einbeck to the north (ancestral doppelbock).

Malting improvements have made today’s wheat beers more refined, but it is the authentic Bavarian wheat beer yeast that links us to those brews of yore. To say that they are vastly different than other top-fermenting yeasts would be an understatement. They breathe more character into a beer than any other single strains, and next to spontaneously fermented brews, produce aroma and flavor complexity without peer. The obvious difference between weizen yeast and even the most estery top-fermenting yeast sheds some light on what beer may have been like long ago, as much of that very character was selected out of the yeast moving forward. There is enough personality in a wheat beer from the yeast to make “session” strength versions of 4.0 percent or less ABV without losing anything, even better for a summer quencher.

Constructing Wheat Beers

While the three versions are different, there are a few guidelines and considerations that we need to bear in mind when composing them. Of course, you can make a hoppy version, one with less wheat or all wheat (possible with all-grain) or a “wheaty” ale, porter, stout or lager using the standard yeasts. This information should be helpful even in those cases.

All-Grain: Authentic Bavarian wheat beers must contain at least 50 percent malted wheat, with most between 50 percent and 70 percent. German wheat malt would be the most true to the style, but North American, British and Belgian maltsters also make suitable versions. A blend of malted wheat and pilsner or two-row will make a hefeweizen, blonde in color. The inclusion of 20 to 30 percent Vienna or dark wheat malt will deepen the color to a handsome burnished-gold. Munich malt adds a wonderful underlying malty character and a reddish tint, essential for dunkelweizen or weizenbock. Caramel or chocolate wheat malt can also be used in these brews, but it is best to restrict them to no more than 5 percent of the grist.

When using wheat at 40 percent or more in all-grain batches, it helps to use a lautering aid, such as rice hulls, to prevent stuck mash since wheat contains no husk. It would be wise to do a protein rest to help break down the excessive protein and skirt potential stuck mash issues. Conduct the saccharification rest in the mid-range, 150 to 153 degrees F to ensure some body. Weizenbier is naturally turbid, so don’t expect perfectly clear wort during vorlauf or great flocculation post-fermentation. You can even eliminate the secondary fermentation.

Extract: Extract brewers can choose between liquid and dried malt extract. The composition is made available by the vendors, and contain both wheat and barley malt. Some are 50:50, while others are 65:35 in favor of wheat, making it possible to compose a wheat-heavy extract beer. Use some pilsner or light DME if you want less wheat and more barley. The extra protein in wheat means that you can forgo bodybuilding specialty malts even in lighter wheat beer recipes. Wheat malt extract combined with amber or Munich malt extract (30 percent of fermentables) and caramel or chocolate wheat specialty malt (0.5 pounds per 5 gallon batch) makes excellent dunkel or bock wheat beers possible.

Liquid yeast options are somewhat limited, but the differences among them are significant. Read the individual specs carefully to see if it will deliver what you want, as the flavor profiles vary immensely from strain to strain. Some are quite mellow, while others are very aggressive. Any of them can be used for the three types of Bavarian wheat beer.

The low end of the recommended temperature range will give a vastly different outcome than those fermented at the higher end. Pay particular attention to the fermentation temperature range suggested by the yeast vendor, as excessive byproducts at too high a temperature might be a bit overwhelming.

Dried wheat yeast capable of bringing a touch of Bavaria to your homebrewery can also be purchased. The ripe aromas and flavors of banana, clove, vanilla, apple, citrus and bubblegum from the yeast make Bavarian wheat beers so appealing and unique. It is the most important decision you’ll make when crafting one.

Hop rates should be low, in the range of 15 to 20 IBU, for all styles, with minimal to no hop aroma. German noble hops and American versions of those work best.

Kegged weissbier and dunkelweizen can be consumed quite young for that fresh, hazy, yeast-driven profile. Weizenbock benefits from a little age, adding a mellow lager-like quality and enhancing the malt notes a bit more. When bottling wheat beers, use a tad more priming sugar than normal as the spritzy nature will not only make it more refreshing, but also will enhance the moussy, billowing head created by the protein-rich wheat.


K. Florian Klemp
K. Florian Klemp is an award-winning homebrewer and general hobbyist who thinks there is no more sublime marriage than that of art and science.