The Herald Trubune
"It's the Rice"
-Anonymous copywriter-
Vol. 9, No. 2
February, 1995
Thu, February 9 Dave West
Tue, March 14 Bock is Best
Thu, April 13
Tue, May 9 Rauchbier
Roundup
Thu, June 15
Sun, July 16 Beer-BQ Weiss
is Nice
Thu, Aug 10
Tue, Sep 12 Best of Fest
Thu, Oct 12
Tue, Nov 14 Renowned Brown
Thu, Dec 14
New members, this is a perfect way to become an instant "old-timer."
So: VOLUNTEER TO HOST A MEETING! You'll be glad you did.
Paul Philippon had a wonderful Strong Scotch "Wee Heavy". Unfortunately, he thinks may have been the last one of that batch. All I can say is, Paul, you'd better make that one again!
From the "for what it's worth department"--an article by David Holzman in a recent issue of ASM News: "Engineered Yeasts Available but Not Yet Used For Brewing"
Brewers could reduce the time it takes to get beer to the market, from the current 3 to 7 weeks to 2 weeks, by taking advantage of genetically engineered yeasts that are being developed in Germany and Japan. However, concern about public reactions to such changes apparently is keeping brewers from introducing these engineered yeast strains into commercial use, according to Ulf Stahl, professor of microbiology and genetics at Berlin University of Technology in Berlin, Germany; Reisuke Takahashi, general manager of Kirin Brewery's Central Laboratories for Key Technology in Yokohama, Japan; and others who described recent developments in this field during the August meeting of the American Chemical Society held in Washington, DC.
Along with ethanol and some minor components that add flavor to beer, yeast fermentation also produces alpha-acetolactate. It quickly is oxidatively decarboxylated to form a compound that imparts a sweet, buttery flavor, which most beer drinkers beside Czechoslovakians do not like. To overcome this problem following fermentation, most beer is allowed to mature, or to lager, for 2 to 6 weeks, depending on conditions. This much time is required for enzymes in the yeast to convert most of the immediately produced diacetyl to acetoin, a innocuous compound with no effect on flavor. "Lagering means your money sits for six weeks in the cellar," says Stahl.
By using genetic engineering to short-circuit the alpha-acetolactate to acetoin pathway in brewer's yeast, the German and Japanese scientists say they will be able to reduce lagering time to about one week. For example, the researchers at Kirin cloned the gene for acetolactate decarboxylase (ALDC), an enzyme which quickly catalyzes conversion of the buttery diacetyl to acetoin, and inserted this gene into the yeast. The gene donor is Acetobacter aceti, a bacterium used to make vinegar.
"Using this transformant we carried out a laboratory-scale fermentation," says Takahashi. The transformed yeast holds the diacetyl concentration to 0.1 mg/liter, compared to 0.6 mg/liter for the nonengineered yeast. The reason that any diacetyl appears in the beer is that some of the diacetyl, or its precursor, alpha-acetolactate, leaks out of the yeast and into the beer before the enzyme, locked inside the yeast cells, can catalyze its transformation, he notes.
By taking a different approach to the genetic engineering of the yeast, the research group at Berlin University appears to have eliminated even the residual diacetyl. Thus, by including in the expression cassette a gene that enables the cell to secrete the decarboxylase enzyme into the brew along with its diacetyl substrate, the conversion to acetoin is more efficient, according to Stahl.
Aside from the dearth of diacetyl, the beers produced by the transformed yeast were virtually identical to those produced by untransformed yeast. "Transformants showed the same characteristics as the parental strain in all tests," says Takahashi. "There was no difference in fermentation profiles." There was also no difference in concentrations of components such as saccharides, from which the yeasts derive most of their energy. "The concentrations of maltose and maltotriose were slightly lower in the beer brewed with the transformant," he adds, "but this degree of difference is sometimes observed in the standard brewing process." Importantly, there is no difference between the flavor of the finished product and that of beer made with unengineered yeast but lagered for longer periods. Moreover, the transformed yeast maintains its ability to produce the ALDC enzyme through eight successive fermentations.
Will the transformed yeast be used commercially for brewing beer any time soon? Takahashi dances around this question. "Our mission is to develop innovative or revolutionary technology and transfer those obtained in the research laboratory to a business division [of Kirin]," he says. "I am not in a position to make clear the answer...but I wish Kirin will commercialize those yeasts in the future."
Use of genetically engineered yeast to brew beer is a bigger problem for the Germans than for the Japanese, according to Stahl. Public opposition to any sort of genetic engineering is so strong that the process is unlikely to be approved anytime soon. For instance, although Germany's diabetics take genetically engineered insulin, the product may not be manufactured locally but must be imported from abroad, he notes.
A. Guinness Son and Company, a brewery based in Dublin, Ireland, also has developed genetically engineered yeast, according to Alvin Young, science advisor and scientific director, Office of Agricultural Biotechnology at the U.S. Department of Agriculture. Once again, despite technical achievements, the company seems to be in no hurry to bring its improved yeast strains into commercial use. "I don't know when we will have a recombinant DNA beer to face the public," he says.
Personally, I can't believe that the only benefit of lagering is to reduce the alpha-acetolactate levels (though I'll be the first to admit I have a lot to learn about brewing). Still, I wonder how long it will take the U.S. Megaswill brewers to embrace these new beasties.
"I love yeast," declared Dan McConnell of Ann Arbor, Michigan, owner of the Yeast Culture Kit Company. McConnell addressed the topic of "Ethanol, Carbon Dioxide and Other Stuff." The latter category includes such compounds as esters, alcohols, aldehydes and diketones. Production of these depends on factors such as yeast strain, food source, reproduction, environment, nutrition and [yeast] health.
Ester production occurs under anaerobic conditions. As oxygen leaves solution, yeast cells direct their energy away from cell wall maintenance and start to produce esters. most important in ester formation are yeast strain and fermentation temperature. Formation of those fusel alcohols that we all love is influenced by yeast strain, temperature, wort agitation, yeast growth and wort composition.
McConnell advocates repitching, for esthetic as well as economic reasons. Many yeast strains change over two or three brews, he said. Commercial yeasts are not propagated in beer wort. The first batch of beer fermented by such a yeast may not show the strain's true character. To illustrate the abundance of yeasts one might use, McConnell showed a list of some 40 varieties of Belgian yeasts that he had quickly jotted down the night before.
"It's a tough job, but somebody's got to do it!"
I was required to visit Hawaii last month in order to present a paper at a conference. Fortunately, mine was the first paper of the first day, leaving lots of time for more important activities like snorkeling and drinking beer. Actually, the state drink seems to be the Mai-Tai, but that's another story.
Asian beers were abundant, and seemed to be fresher than we get them here. A bottle of Singha nicely complemented a Thai dinner my second evening on Maui. The New Zealand beer, Steinlager, was also fresher and more flavorful than I remember from previous encounters with it. It went very well with sushi.
Finally, on my last day on Maui, I saw Maui Whale Ale on the beer list. I had to try this one. When it came, I carefully perused the bottle to find "Maui Brewing Co, Paia, Hawaii. Brewed and Bottled by Weinhardt Brewing, Portland, OR." Well, it was still a nice, fruity ale, and it went very well with the over 10-foot surf outside the window.
The next morning, we were wandering around downtown Honolulu. In the Aloha Tower shopping center, we spotted a Gordon Biersch brewpub! Luckily, it was open, so we walked right over to the bar. The bartender pulled samples of Export, Oktoberfest, and Dunkel, and I selected a pint of Oktoberfest. Quite nice, if I do say so! The bartender, upon learning that I am a homebrewer, brought over a couple of issues of Brew Hawaii, the "newspaper" of the Hawaiian Homebrewers Association. From it, I learned of a recently opened microbrewery and of a brewpub in Lahaina (had we but known of it a few days earlier, when we were there!)
Bock is Best March 20 Rauchbier Roundup May 22 Weiss is Nice Aug 14 Best of Fest Oct 23 Renowned Brown Dec 4
Upcoming judging events include the AHA National Homebrew Competition 1st round in Chicago, April 28-30. There will be a car-pool. Others include: Mazer Cup Mead, May 26; Small Beer, June 24; State Fair, August 12 or 19; Taste of the Great Lakes late October; Chicago Real Ale Fest October 13-14.
Competition Name Entry Deadline Contact
Commander Saaz's Interplanetary Feb 14 Carl Saxer, 407-649-6717 (Florida)
Central Illinois Feb 18 Tony McCauley, 309-664-6284 (Illinois)
2nd Queen of Beer (women only) Feb 24 Mar 3 Elizabeth Zangeri, 916-626-7733 (California)
America's Finest City (San Diego) Feb 27 - Mar 8 Skip Virgilio, 619-566-7061 (California)
5th March Mashfest Mar 10 (Mar 3) Brian Walter, 303-493-2586 (Colorado)
Hop into Spring (hoppy styles) Mar 1 - Mar 13 Gary Spiess, (319)455-2135
4th Southern New York Spring Comp Mar 16 Ken Johnsen, 718-667-4459 (New York)
Great Maple Brewoff Mar 17 Andy Patrick, andnator@mcs.com (Chicago)
2nd Greater Wichita Open Mar 17 Lee Bussy, 316-267-2391 (Kansas)
Brewers of South Suburbia (BOSS) before Mar 25 Al Korzonas, 708-430-HOPS (Illinois)
9th Bluebonnet Brewoff Mar 18 Pat Morrison, 817-383-4399 (Texas)
5th Dukes of Ale Spring Thing Mar 25 Guy Ruth, 505-294-0302 (New Mexico)
Bidal Society of Kenosha Apr 15 Carol DeBell, 414-654-2211 (Wisconsin)
Chili Cookoff and Beer Brewoff Apr 18 Jana Stevens, 303-241-0070 (Colorado)
Big and Huge May MHTG, P.O. Box 1365, Madison, WI 53701-1365
4th Mazer Cup Mead Competition May 8 - 19 Dan McConnell, 313-663-4845
Small Beer Competition May 29 - June Spencer Thomas, 313-994-0072
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Michigan State Fair July 28 - Aug Hal Buttermore, 313-663-1236
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February, 1995: Since I'm now a few months behind in reports, I'll be combining payments and funds received over those months in this report. Starting balance: $357.26. I received '94 dues of $5 from Karl Brosius and $2.50 from Mark Hogle; I received 1995 dues of $15 each from Dave West, Bill Pfeiffer, Jon Van Eck, Dave Van Eck, Rob Collier, Ed Boucher, Eric Engelmeier, Hall Buttermore, Pete Sobczak, Bob (& Jean) Freligh, Pete Holmes, Steve Yalisove, Jack Mercer, Bill Holmes, Arthur Howard, Mike Tomaszewski, Paul Ruschmann, Chris Fraleigh, Jim Johnston, Tim Belanger, Dennis Leland, Don McBride, Dennis Wilmarth, Mike Lumm, Mike O'Brien, and Dennis Raney; and dues and a donation of $20 from John Alguire; I received a total of $64, $30, and $30 from the raffles for November, December, and January, respectively; I also received $10 from Allen Pagliere for the use of the pico-Brewery. This made for a total of $566.50 taken in.
The pico-Brewery Sinking Fund now stands at $151. I'm no longer keeping the pico-Brewery at my house; Bill Pfeiffer has it hostage up in Brighton, so if you want to use it, call Bill at (810)229-0727. It's a great system and members get to use it for only $1/gallon of wort made. Hey, Bill, if you loan it out and collect money for its use, give it to me!!
I have paid out $68.85 to Beer Across America for the November, December, and January selections; I paid $96 to the Postmaster for three rolls of 32cents stamps; I reimbursed Spencer Thomas $32.22 for December copies; I paid $52.94 to Kolossos Quick Copy for November copies and $10.34 for January copies; I reimbursed Tom Dimmer $11.39 for his entry in the Club-Only competition; all this made for a total paid out of $271.74. This leaves a balance in the checkbook of $652.02; the club owned 3 rolls of 32cents stamps and less than a roll of 29cents stamps before this newsletter went out.
Karl Brosius 606 E. Ann #2, Ann Arbor, MI 48104
Thursday, February 9, 7:30PM
2920 Debbiwood Ct., Milford
Dave and Linda West's house, 810-685-1888
There's a map inside. The meeting will probably be in Dave's "barn." That's the large garage-like building behind the house.
If you're interested in car-pooling, show up at the Merchant of Vino on Plymouth Rd by 7:00 ("first bus") or 7:30 ("second bus"). Each group will arrange drivers among themselves. Meet in front of the store (or inside if the weather is awful).
Guide for New Members Bring 1-2 bottles per batch of your beer that you'd like to share, or an interesting commercial beer. Bring tasty munchies to cleanse the palate and sop up the alcohol. Feel free to share and sample with other members and make and accept constructive comments; making better beer or curing ailing ales is our interest! Please observe good judgment while imbibing and don't drive while intoxicated.
Ann Arbor Brewer's Guild
c/o Rolf Wucherer
1942 Steere Pl.
Ann Arbor, MI 48104