Brewers Association

Wheat's Not Just for Baking Bread

Wheat's Not Just for Baking Bread

Wheat's Not Just for Baking Bread

By Stan Hieronymus

Less than one-tenth of 1 percent of wheat grown in the United States ends up malted for use in brewing beer. Guess who the farmers are thinking about when they choose what to plant? They understand that to earn top dollar, wheat must be fat in protein, because the higher the protein, the higher the gluten strength. The higher the gluten strength, the easier to produce those billowing loaves of bread. That the proteins and gluten may present problems for a brewer makes no difference. 

Contrast that to barley. The American Malting Barley Association works to ensure an adequate supply of high quality malting barley through the development of improved malting barley varieties. Malting barley, which must meet exacting standards, earns a farmer 30 percent more than feed barley, and double the return on variable costs. No variety of wheat earns a similar premium, and wheat sells for less than malting barley but more than feed barley.

Does the apparent lack of love present potential problems when a brewer goes shopping for malted wheat for brewing? Not necessarily. Belgian and German brewers made do for hundreds of years with whatever was grown in a nearby field. However, they sometimes used laborious and complicated mashing regimens; it wasn’t until the 1970s that the Germans discovered what unlocks the distinctive clove character in hefeweissbier, and more recently studies out of Belgium indicate that at a certain level more wheat in the grist reduces haze.

American craft brewers have good reason to pay attention. For instance Blue Moon Belgian White outsells Samuel Adams Boston Lager and Sierra Nevada Pale Ale; AB InBev launched Bud Light Golden Wheat in October with a $30 million advertising budget; and Sierra Nevada’s Kellerweiss, fermented in open squares, was one of the most talked about newcomers of the recent summer.

Three very different beers, different still than Widmer Hefeweizen, Boulevard Unfiltered Wheat, Bell’s Oberon, Goose Island 312 Urban Wheat and even Three Floyds Gumballhead. The first four are flagship beers and Nick Floyd reports that some months Gumballhead competes with Alpha King as the Indiana brewery’s top seller.

Why? What does wheat change?

Hey, Good Lookin’

Neither Widmer Brothers Brewing nor Boulevard Brewing initially planned to sell their wheat beers unfiltered and neither would have predicted cloudy beers would end up being such strong flagships. “If our beer was a little cloudy people thought there was something wrong,” Rob Widmer said, remembering when the brewery introduced a filtered wheat beer in 1985. Because the Widmers’ filter was rudimentary, they soon got phone calls. “People would complain and we’d ask what it tasted like,” he said. The customers weren’t about to find out. “They’d say, ‘We’re not going to drink it. It’s gone off.’”

Not long after the Dublin Pub in Portland asked the Widmers for a beer that could be sold “cask conditioned,” cloudy became a badge and Widmer Hefeweizen a benchmark beer.  “How do you stand out?” asked Steven Pauwels, Boulevard’s Belgian born brewmaster who joined the company in 1999. “Color and cloudiness. That’s all you have.”

Germany’s younger drinkers fueled a resurgence in hefeweissbier popularity beginning in the 1980s in part because it looked “natural,” containing both “whole grains” and yeast in suspension. Women’s magazines touted the benefits of hefeweissbier for the skin and other publications listed the wide variety of vitamins in yeast. They probably should have mentioned that brewer’s yeast contains more uric acid than most other food products (more than double baker’s yeast, which itself is higher than most), and that increased levels of uric acid in the blood may lead to gout.

Wheat malt not only contains more proteins than barley, but also more high-molecular-weight proteins. Glutens comprise 80 percent of the proteins (compared to 35 percent in barley). Proteins in suspension contribute to distinctive cloudiness and thick and lingering foam, but also chill haze and eventually stability problems. The thicker mash, and because wheat berries lack husks, makes lautering a challenge, although that’s a production rather than flavor issue. Research at Weissbierbrauerei G. Schneider & Sohn has found that with protein over 13 percent and the Kolbach index (the relation of the soluble protein percentage on the total nitrogen percentage) above 45 percent diacetyl becomes a larger problem.

“The stability of your cloudiness is very complex,” said Andreas Richter, quality manager at Weyermann Malting Company in Germany. “It depends on both the yeast strain and the wheat variety. The big part is not yeast, but proteins. Especially the stable cloudiness. You have to find your own secret. That is very difficult.”

In fact, so complex that research at the beginning of the 21st century indicates that larger quantities of wheat in the grist may reduce haze stability. You might want to read that again. One study included unmalted wheat, the other malted wheat. In both cases researchers found that haze intensity increased at wheat levels of 15 to 20 percent, then began to decrease with additional wheat additions, so that at 40 percent beer contained almost no permanent haze after just three weeks. The particles obey Stokes’ Law: “Wheat gluten proteins were found to be haze active in that they interact with polyphenols, and protein-polyphenols complexes. At low gluten levels, a haze is formed, although at higher gluten levels, these insoluble complexes are too large to stay in suspension and precipitate.” Basically, small particles stay in suspension, while larger ones drop out.

Both studies indicated choice of barley malt also influences haze. For instance, using a malt such as Scarlett with a higher proteolytic activity caused an increased breakdown of wheat protein during brewing, and smaller proteins led to smaller haze particles and less settling. The researchers found that wheat beers brewed with a high modified malt contain more haze than those brewed with a low modified malt.

Historically German breweries have used a step mash, often with decoction, and one of the results is smaller protein particles. However, like several other larger breweries, Spaten, which makes Franziskaner Hefeweissbier, abandoned decoction in 2000 and now employs a single infusion mash at 144° F (62° C). Traditional rests, particularly a protein rest at 122° F (50° C), further break down proteins with high molecular weight.

Although many American breweries, particularly at the pub level, are not set up for decoction or step mashing, that doesn’t keep brewers like Jonathan Cutler at Piece Brewery & Pizza in Chicago from throwing in a rest. Cutler’s Top Heavy Hefeweizen and Dark-n-Curvy Dunkelweizen consistently win awards at the Great American Beer Festival and World Beer Cup. He mashes in dry at 118 to 122° F (48 to 50° C) for the protein rest, then uses boiling water to raise the temperature to 155° F (68° C).

21st Century Options

Several German breweries that put a one-year best by date on their beers package hefeweissbiers without yeast, carbonating them in tanks and using flash pasteurization to assure proteins remain in suspension. One theory is that this denatures the smaller proteins, assuring they will not clump together and fall out of suspension. By removing the yeast, the breweries assure it will not drag down proteins as it settles.

Belgian and German brewers long recognized the importance of using “powdery” yeast for just that reason, further suggesting consumers rouse the yeast while pouring a beer. Draft hefeweissbier is relatively new in Germany—for instance, Schneider and Sohn did not start kegging beer until 1993. Schneider, which continues to use speise (unfermented wort) for traditional bottle conditioning, ships its kegs upside down so that yeast will be stirred just before a keg is tapped.

New Belgium Brewing in Colorado decided to flash pasteurize its Mothership Wit after conversations with German brewers. Assistant brewmaster Grady Hull said the Germans talked about denaturing the yeast cells, helping stabilize flavor because that removes the danger of autolysis. New Belgium, like other brewers selling cloudy beers, includes instructions on the bottle urging customers to swirl the final portion before pouring, thus tossing yeast and protein that have settled back into suspension.

Pub brewers, knowing their wheat beers will be poured from serving tanks holding seven barrels or more, don’t have that luxury. Some, as well as packaging microbreweries, have turned to additives to provide stable turbidity. One, Tanal A, is extracted from Chinese gallnuts, which contain the highest naturally occurring level of tannin. “The structure is similar to a polyphenol,” explained Jess Caudill of Wyeast Laboratories, which sells the additive. “It acts like chill haze, and eventually will settle out.” Developed in Belgium as a fining agent for the wine industry, it crossed over into the beer world. “It’s growing in popularity,” Caudill said. “We have quite a few customers who use it all the time, but they don’t market that fact.”

Derek Osborne, director of brewery research and development for BJ’s Restaurants, enthusiastically endorses Tanal A. He uses it in both wit beers and weizen beers at BJ’s Chandler, Ariz., brewery and has won medals at the Great American Beer Festival and World Beer Cup with them. “We figured we are the R&D brewery so we might as well give it a try,” he said. Now other members of the chain follow the same recipe. “A little goes a long way and the lower amount of yeast in your beer, the better,” Osborne said. Tanal A must be hydrated in de-aerated water or carbonated beer, then blended with a batch post-fermentation at a rate of about 4.5 grams per barrel.

Brewers Supply Group sells the second alternative, called Biocloud. A yeast-derived cloud system, extracted from primary grown Saccharomyces cerevisiae cells, Biocloud is added post-filtration at between 40 and 100 grams per hectoliter (roughly 45 to 120 grams per barrel).

“It disperses really well,” said John Guzman of Brewers Supply Group. “There are no problems with stratification.”

Is That the Wheat or the Fermentation?

What does wheat taste like? Bob Hansen, manager of technical services at Briess Malt & Ingredients Company, has as good an answer as anybody. “Wheaty, earthy. It is different, but you’d be surprised how non-different it is,” he said. “You can use wheat to make a pilsner.”

Jean-Francois Gravel of Dieu du Ciel! in Montreal likes the character unmalted wheat adds.  “To me, wheat has a very delicate bready flavor with some acidity or refreshing tartness. I think the barley has more pronounced grain flavor and a sweeter perception,” he said. “If you eat raw wheat and malted wheat you will see the difference of texture right away because the malted wheat is more crumbly and easy to crush. But the flavor difference between the unmalted and malted wheat is very subtle. The malted wheat will have a bit more…malty flavor.”

Of course, when consumers describe Belgian white beers or southern German weizens they usually start with flavors and aromas created during fermentation, or in the case of white/wit beers by the addition of spices, which don’t necessarily depend on wheat.

Although brewers long ago mastered delivering the clove-like aroma and flavors that make German weizen beers different, not until the 1970s did they discover that unique weizen yeasts decarboxylize ferulic acid to 4-vinyl guaiacol, the phenol responsible for that character. Barley and oats contain significant amounts in the subaleurone layer, while wheat has it primarily in the aleurone. 

Recent studies indicate that although wheat contains much higher levels of ferulic acid, it is released from its bonds with barley malt more easily than from wheat. It is freed by water extraction and enzymatic activity, and work by Vanbeneden et al found it maximized at temperatures between 104 and 109° F (40 to 43° C) at a pH of 5.8. They also reported that mash thickness, grist coarseness and composition, and the stirring regime had a pronounced effect on the release of ferulic acid. Other studies suggest a temperature of 113° F (45° C) and a pH of 5.7.

Vanbeneden’s paper indicated that mashing in at 131° F (55° C) rather than 113° F results in lowering 4-vinyl guaiacol content by 30 percent. Like the studies centered on haze, his concludes that malted barley selection can be as significant a variable, in this case in flavor and aroma formation.

Before writing Brewing with Wheat I collected questions craft brewers would like answered. One asked for detailed data about the level of ferulic acid in specific barley and wheat malts. Maltsters said that’s not something they can provide. However, they are intent on delivering malts that act consistently if not the same in every brewhouse.

In Germany, Weyermann Malting has worked with agricultural partners to develop wheat varieties designed for brewing. “In former times we had to use bakery varieties for beer,” said plant manager Juergen Buhrmann. “Now there are specially developed malts. A few breweries still want to use the baking varieties.”

“Wheat beer is such a complex thing that it’s difficult to give specific directions,” added Richter. “The brewer should figure out what conditions are best for his beer.”

When Dan and Deborah Carey founded New Glarus Brewing in Wisconsin in 1993, they thought it would be fun to build a weiss-only brewery. “Of course we’d have been out of business long ago,” Dan Carey said, laughing at himself. However, by the time the Careys brought their $21 million hilltop brewery online in 2007, he had a good idea what he wanted, including purpose-built open fermenters for wheat beers. “We did a lot of experiments,” Carey said. He and his staff tested half a dozen yeast strains, compared red wheat to white, changed mashing regimens and fermentation schemes. “It became glaringly evident which one of each was good for us. For every brewery it will be different.”

Further Reading

Ockert, Karl (editor). Fermentation, Cellaring, and Packaging Operations. St. Paul, Minnesota. Master Brewers Association of America,2006, 110-118.

Depraetere, S. et al. “Wheat Variety and Barley Malt Properties: Influence on Haze Intensity and Foam Stability of Wheat Beer.” Journal of Institute of Brewing, 2004, 110(3), 200-206.

Delvaux, F., et al. “The Effect of Wheat Malting on Colloidal Haze of White Beers.” Master Brewers Association Technical Quarterly, 2004, 41(1), 27-32.

Vanbeneden, N., et al. “Formation of 4-vinyl and 4-ethyl derivatives from hydroxycinnamic acids: Occurrence of volatile phenolic flavour compounds in beer and distribution of Pad1-activity among brewing yeasts.” Food Chemistry, 2008, 107, 221-230.

Thanks to Dr. Gary Spedding of Brewing of Distilling Analytical Services for providing several of these documents.

Stan Hieronymus is the author of Brew Like a Monk. This article was drawn from his new book Brewing With Wheat, which is scheduled to be available from Brewers Publications in February 2010.

 

Photo © 2010 Shutterstock, LLC.

 

 

Btn_back

No comments.

Zach Nichols

Zach Nichols

Co-founder of Sanitas Brewing Co. in Boulder, Colo. More