HOME  >  Newsletter  >  VOLUME 60, No.1 - 2000

ASBC Newsletter

The end of one century and the start of another (and, in this case, eventually--a new millennium) must be pause for reflection. By the time you receive this edition of the Newsletter, and assuming you are still in the holiday spirit, you might be reading this column while enjoying an ice cold lager or a tasty ale, sipping a full strength barley wine or bock, being refreshed by a wheat beer or fruit brew, or just mulling over the dark and delicious, assertive attributes of a porter or stout. Whatever malt beverage is your preference, and wherever you are in the world, all of us must agree that our technical understanding of beer--the brewing materials, the processes by which it is produced, its physical properties, flavor control, sensorial makeup, and ultimate shelf life--have made significant progress, particularly over the past 100 years. And although beer has been, historically, a "safe beverage" of choice, there is no doubt that, today, we have a far greater appreciation of the hazards that could afflict our noble beverage, allowing us to anticipate enhanced quality and safety standards and to implement processing equipment to help us establish superior control and product consistency.

In product development, we might enjoy "rediscovering" lost flavors of yesteryear, but I doubt whether we would want to return to the days when our understanding of the brewing process prompted more than a little "experimentation." Established brewers have always tried to produce good beer. However, I was recently intrigued to read in a book titled Country House Brewing in England by Pamela Sambrook that hops could be replaced with ground ivy or long pepper! In addition, yeast (which has been appreciated only for about 150 years) could be replaced by soap, a mixture of flour and eggs, essential oil of barley, and "quintessence" of malt, while the beer itself might be flavored with anything from dandelions to new hay! So-called "foxed" or "ropey" beer might attract the additions of chalk, unslaked lime, powdered oyster shells, wormwood, oatmeal, bay salt, isinglass (still used), or, more drastically, a mixture of mutton, tartar salt, and eggshells!

These days, all brewers, large and small, take an enormous pride in producing the very best products possible, often spending a premium to acquire better brewing materials and processing/monitoring equipment, having happy and healthy yeast, and keeping the process safe and sanitary. All of this, however, would not be possible without the sharing of technical knowledge among brewers, the establishment of standard methods of analysis as a basis for comparison, the designing of instrumentation to take us to the next level of sensitivity or resolution, and a commitment to continuous improvement through research and development.

The American Society of Brewing Chemists has, from its founding date, been instrumental in promoting a camaraderie among the world’s brewers to help achieve the above. As in our "sister" international organizations, which I listed in my column in the last issue of the Newsletter, a deep sense of responsibility for our industry and for the consumers of our products has always been our serious commitment. Therefore, the ASBC must never allow itself to stand still, must always recognize the needs of its members, and must continually "rediscover" itself by bringing in new active members to and from the industry who will make a difference in the future, through contributing to the continuously changing structure and function of our society and our industry. Hence, our updated strategic plan, which we have spent so much time communicating over the past few months.

I started my career in the malting industry, where (in a very old-fashioned malthouse, which no longer exists), colored malts such as crystal, chocolate, and black malts were literally roasted in huge pans on individual brick kilns fired with "faggots" of wood. Quality control was, as you can imagine, of "burning" importance and, quite literally, based on taste (mostly "seared" taste buds)! Probably this pyrotechnic experience was commonplace at the beginning of the century, and, thank goodness, advances have provided more precise (and safer!) methods of making specialty malts. When one considers the enormous technical advances achieved over the past 100 years, and particularly since 1934, to which members of the ASBC have contributed, one must realize that we really have achieved an amazing array of different technologies on which to make and measure our products, unfortunately, far too many achievements to list in this issue of the Newsletter. But whether we are speaking of malting or mass spectrometry, of glycolytic flux or "g" proteins, of our continually increasing knowledge of hops and the huge variety of hop extracts, including those that are light-stable, or simply of the intricacies and interaction of beer foam components--it really all boils down to one thing. By producing a good, popular, responsible product to a high, consistent, and safe standard, the chances of survival for our industry are very high! And the chances of "delighting" our consumers are great!

All of us, from the Board of Directors to the ASBC Executive Office, wish you and your families a wonderful 2000!

--David Ryder

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Local Section 1--New York
Section 1 is planning a meeting in December. We have two people interested in being members of our local chapter at the local plant. We are also talking to a couple people who have expressed some interest.

Local Section 2--St. Louis
Local Section 2 kicked off its 1999–2000 season on Sept. 29 with a meeting at The King and I Restaurant in St. Louis. ASBC President-Elect Nona Mundy presented the attendees with an interesting and challenging insight into the ASBC with her topic, "ASBC--2000 and Beyond."

The October meeting was held at The Trailhead Brewery in Old St. Charles, MO, and was sponsored by Perkin-Elmer Corp. Dr. John Witte, Director of Brewing Operations at Trailhead, presented to the members and guests "The History of the Trailhead Brewery" and afterwards gave a tour of the microbrewery.

Our 1999–2000 sponsors are Perkin-Elmer, McCormick & Co., VWR, Foss North America, and Anheuser-Busch CQA and BTS Departments.

The remaining meeting schedule for the Local Section 2 is as follows: Nov. 19, Jan. 26, Mar. 4 (Mardis Gras Party), Mar. 29, Apr. 19, May 25, and June 10 (Annual Summer Outing).

Local Section 4--Milwaukee/Chicago
Local Section 4 will have a meeting on Dec. 2 at Leinenkugel's 10th St. brewery in Milwaukee. It will include a tour of the facility and a presentation on the 1999 barley crop given by David Newell and Tom Wolf of Miller Brewing Co.

In February, Section 4 will have a Family Night event. The date and location are to be determined.

Local Section 7--Northwest
Section 7 held its last meeting in Seattle on Oct. 22 and 23. The technical session covered a variety of hop speakers who discussed topics from breeding hops to sensory evaluation. Our next meeting will be in Hood River, WA, on June 2 and 3.

Local Section 8--"Wild West"
The 15th meeting of ASBC Local Section 8, "Wild West," was held at the Coors Brewing Co. in Golden, CO, on Nov. 4 in conjunction with the Rocky Mountain MBAA. Twenty-five attendees gathered for food, beer, and socializing from 5:30 to 7:00 p.m., paying $15 each at the door. The business meeting was called to order by Mike Joyce for Chairman Patrick Dobolek, who was in Germany expanding his brewing education. Mike read the minutes and treasurer report, which were accepted as written. Rob Maruyama shared the latest news from the national ASBC Board meeting held in September.

The technical presentation, by Rolf D. Schmidt from the A. Gusmer Co., was an excellent overview of beer filtration and new filtration products available to handle any brewer’s needs. The meeting concluded with dinner and door prizes.

The next ASBC local section meeting will be held on Feb. 18 at the Rocky Mountain Micro-Brewing Symposium in Colorado Springs.

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1999-2000 Technical
Subcommittee Reports

The Technical Committee and subcommittee chairs met on October 8, 1999, in St. Paul, MN, to finalize details for this year’s subcommittee work. There will be a total of 10 technical subcommittees and four check services. Of the technical subcommittees, three are new (having been recommended by the Subcommittee on the Coordination of New and Alternate Methods of Analysis), four are in their second year or more, and three are standing subcommittees. The standing subcommittees are International Methods, Soluble Starch, and Coordination of New and Alternate Methods of Analysis. The check services are Beer Analysis (managed by Bahram Grami), Hop Analysis (managed by Steve Kenny), and Malt Analysis and Barley Analysis (both managed by John Barr).

The subcommittee chairs did an excellent job in preparation for the fall meeting, resulting in productive discussions of each method. Special appreciation is due to each of the chairs for their hard work and dedication.

Your Technical Committee is composed of Steve Nyarady (chair), Dirk Bendiak, Cindy-Lou Dull, Jim Murphey, Paul Schwarz, and Greg Casey (ex officio).

Coordination of New and
Alternate Methods of Analysis
This is a standing subcommittee whose function is to collect, from various sources, new and alternate methods of analysis that may be useful to the industries our Society serves. These methods are reviewed to establish their merit and usefulness, and a recommendation regarding collaborative testing is made to the Technical Committee. The subcommittee is also charged with periodically reviewing existing methods for accuracy and usefulness. The subcommittee chair is John Engel.

John Engel
Miller Brewing Co.
P.O. Box 482
Milwaukee, WI 53201-0482
414/931-2099
Fax 414/931-2506
E-mail engel.john@mbco.com

John is the corporate quality services manager of product for the Miller Brewing Co. He has served in this position since November 1996. Engel began his career with Miller Brewing Co. at the Albany, GA, brewery in June of 1980. During his 19 years with the company, he has held numerous positions within the company’s Quality Organization at various locations, which include the Albany, GA, brewery; Milwaukee, WI, brewery, corporate offices; and Trenton, OH, brewery. Positions held during this time include the following: packaging quality analyst, control chemist, technical packaging supervisor, packaging quality supervisor, product quality supervisor, quality systems technologist, laboratory manager/core quality leader, and corporate quality services manager-product.

Engel obtained a B.S. in chemistry from Carroll College in Waukesha, WI. He also holds a Diploma in Brewing from the Siebel Institute of Technology.

Subcommittee members: D. Bendiak, C. McLinn, R. Smith, and S. Nyarady (ex officio).

Selective Measurement of Acetohydroxy Acid
Precursors of Vicinal Diketones
This is the fourth year for this subcommittee formed to evaluate an alternative method for vicinal diketone precursor conversion based on the selective measurement of acetohydroxy acid precursors using aniline hydrochloride. In its first year, unacceptable repeatability and reproducibility coefficients of variation were found. In the second year, no collaborative testing was initiated. In the third year, the calculated levels of acetolactate were found to be 10–20 times lower than expected, based on the amount of precursor sent to each collaborator, suggesting that there may have been a problem with the saponification step in the procedure. This year, the collaborative will be repeated after additional ruggedness testing to perfect the steps to prepare a stable spiking solution. The subcommittee chair is David Maradyn.

David Maradyn
Labatt Breweries of Canada
P.O. Box 5050
197 Simcoe St.
Research Dept.
London, Ontario
Canada N6A 4M3
519/667-7345
Fax 519/667-7350
E-mail david.maradyn@labatt.com

David received his Ph.D. degree in organic chemistry from University of Western Ontario in London, Canada, in 1995. He joined the Advanced Research Department of Labatt Brewing Co. Ltd. in London, ON, in 1995 as a postdoctoral fellow and has since progressed to his current position of research scientist at Labatt.

Subcommittee members: C. Almen, J. Castane, P. Chandley, M. Clements, K. DeVries, C. Eckermann, C. Garcia-Fuentes, R. Haag, G. Perez, A. Tinginys, and D. Bendiak (ex officio).

Surface Hygiene Testing Using
ATP Bioluminescence
This is the second year for this subcommittee formed to evaluate a general swabbing method to determine the hygiene of brewery surfaces using any type of adenosine triphosphate (ATP) bioluminescence instrument. In the first year, the objective was to determine whether reproducible surface hygiene results could be achieved across multiple laboratories with multiple instruments utilizing a common swabbing method. This year, the collaborative study will apply the surface swabbing method to blind test samples with varying levels of yeast suspension. The subcommittee chair is Lisa Beckler Andersen.

Lisa Beckler Andersen
Coors Brewing Co.
P.O. Box 4030
Mail BC 370
Golden, CO 80401
303-277-2807
Fax 303-277-6640
E-mail lisa.anderson@coors.com

Lisa received her bachelor’s degree in environmental, population, and organismic biology from the University of Colorado, Boulder. She has worked at Coors Brewing Co. since 1990 and is currently a microbiologist in the Product Control Laboratory in Golden. She has been involved with ASBC as a subcommittee member and as a poster presenter.

Subcommittee members: A. Aitchison (EBC), D. Bendiak, F. X. Castañé Sitjas (EBC), K. Dewey, J. Dirksen, L. Franken, M. G. González Juárez, L. Laidlaw, M. Land, G. Perez, A. Price (EBC, IoB), J. Sheehy, E. Storgards (EBC), H. Taguchi (BCOJ), P. Vann, G. Wright, and C.-L. Dull (ex officio).

Headspace Solid-Phase Microextraction for
Determination of Hop Essential Oils
This is the second year for this subcommittee formed to evaluate solid-phase microextraction as an alternative to Hops-13 steam distillation for the determination of the essential oils humulene and caryophyllene in hops. No collaborative work was performed during the first year due to time constraints of the previous chairman. The subcommittee chair is Stephen Kenny.

Stephen Kenny
Washington State University
IAREC
24106 N. Bunn Rd.
Prosser, WA 99350-8694
509/786-9284
Fax 509/786-9370
E-mail skenny@tricity.wsu.edu

Steve is a research scientist in hop genetics and breeding at Washington State University. He received a B.S. degree in biology with a minor in chemistry from Frostburg State University. He graduated with a Ph.D. in plant genetics from Colorado State University. Steve joined Washington State University in 1981, where he is responsible for developing new hop cultivars and hop germplasm with improved resistance to hop pests. He has been a member of several ASBC subcommittees for hop analytical methods.

Subcommittee members: L. Barber, M. Clements, P. Hill, G. Nickerson, T. Pruneda, R. Smith, A. Tinginys, and J. Murphey (ex officio).

Beer Color Using Tristimulus Analysis
This is the second year for this subcommittee formed on interest expressed by the ASBC membership and the general business meeting at the 1998 Annual Meeting in Boston to examine the use of tristimulus-based analyses in the evaluation of beer color. The subcommittee chair is Michael Clements.

Michael Clements
Guinness Research and Development
St. James Gate
Dublin 8
Ireland
9-011-353-1-408-4695
Fax 9-011-353-1-408-4816
E-mail Michael.Clements@guinness.com

Subcommittee Members: R. Ackermann, C. Eckermann, P. Gomez, T. Haukebo, A. Vieira, M. Vincent, and P. Schwarz (ex officio).

Soluble Starch
The Soluble Starch Subcommittee is a standing subcommittee whose goal is to coordinate a testing program for soluble starch that will ensure a consistent supply of quality starch for the Society. To further this goal, the subcommittee monitors process methodology utilized in the production of the starch, investigates improved methods for starch quality testing, and evaluates potential new suppliers of starch. The subcommittee chair is Michael Joyce.

Mike Joyce
Coors Brewing Co.
Mail Stop BC 600
P.O. Box 4030
Golden, CO 80401-0030
303/277-6222
Fax 303/277-6834
E-mail mike.joyce@coors.com

Mike received his bachelor’s degree in chemistry from Metropolitan State University in Denver, CO. He has worked at Coors Brewing Co. since 1976 and is currently a malting/brewing chemist in the Product Control Laboratory in Golden, CO. He has been involved with the ASBC as a previous subcommittee chair and member.

Subcommittee members: E. Austin, S. Chan, D. Christopher, B. Johannes, H. Kuester, M. Maurice, M. Ono (BCOJ), R. Sieben, G. Smith, W. Swenson, and P. Schwarz (ex officio).

Determination of DMS Precursors in Malt
by Headspace GC with Application
of Nitrogen Purging of Extracts
This is the subcommittee’s first year, formed on a recommendation from the Subcommittee for the Coordination of New and Alternate Methods of Analysis. The effort will collaboratively study the method of Yang and Schwarz as an alternative method to Malt-14. The subcommittee chair is Richard Joy.

Richard Joy
Westcan Malting
Box 113
Alix, Alberta
Canada T0C 0B0
403/747-2777
Fax 403/747-2660
E-mail rich@westcanmalt.com

Rich received his B.Sc. in cellular, molecular and microbial biology and his Ph.D. in developmental plant physiology, both from the University of Calgary. After graduating, he took up a post doctoral fellowship at Tohoku University in Sendai, Japan, where he investigated secondary plant metabolism and its association with the cell cycle in cell suspension cultures (1991–1994). After returning to Canada, he joined the Promotor Technology Group at the National Research Council of Canada, Saskatoon, SK. At the NRC he successfully isolated and characterized the majority of the lignin and phenylpropanoid genes from Brassica napus, which he subsequently used to produce transgenics. In 1997, Rich joined Westcan Malting Ltd. in the capacity of manager of quality control and technical services.

Subcommittee members: D. Bendiak, M. Maurice, C.-L. Dull, C. Garcia-Fuentes, R. Haag, E. Kouhi-Lavender, G. Laycock, D. Thompson, and Jim Murphey (ex officio).

Malt Grind Analysis Using Standard Sieve Test
This year marks the subcommittee's first year of existence. It was formed on a recommendation from the Subcommittee for the Coordination of New and Alternate Methods of Analysis. The subcommittee chair is John Barr.

John Barr
North Dakota State University
Dept. of Cereal Chemistry and Technology
Fargo, ND 58102
701-231-7732
Fax 701-231-7723
E-mail John_Barr@ndsu.nodak.edu

John received a B.S. degree in earth science from North Dakota State University in 1984. That same year, he joined General Nutrition Mills in Fargo, ND, working in quality control. During 1987, John worked in the Chemistry Department at the American Crystal Sugar Research Center in Moorhead, MN, assisting in the process control of five beet sugar extraction plants. In 1988, he moved on to National Sun Industries in Enderlin, ND, as a laboratory technician. He worked with analyses associated with the operation of a sunflower and soybean oil extraction plant. His experience with oil seeds brought him to North Dakota State University in Fargo, ND, in 1990, to work in the Department of Cereal Science with the food science program. In 1991, John joined the Barley and Malt Analytical Laboratory within the department. Presently, he conducts and helps to coordinate the survey of barley quality in the Dakotas and Minnesota. He is also involved with the quality analysis of the NDSU barley-breeding program. John is a member of ASBC and is the manager of the ASBC Malt and Barley Check Services.

Subcommittee members: D. Cairney, P. Gualdoni, G. Kustelski, M. Joyce, C. McLinn, G. Pili, W. Swenson, R. Ulmer, and P. Schwarz (ex officio).

Citrate Buffered Methylene Violet Stain
for Yeast Viability
This is the subcommittee’s first year. It was formed on a recommendation from the Subcommittee for the Coordination of New and Alternate Methods of Analysis. This collaborative will test the proposed method against Yeast-3A. The subcommittee chair is Lyn Kruger.

Lyn Kruger
Siebel Institute of Technology
4055 W Peterson Ave.
Chicago, IL 60646-6001
773/279-0966, ext. 125
Fax 773/463-7688
E-mail Lyn@siebelinstitute.com

Lyn Kruger has 21 years brewing experience in the fields of yeast metabolism, yeast management, fermentation, and microbiology. She joined the South African Breweries as development microbiologist in 1978. She held various positions in the company relating to yeast research, yeast technology, microbiology, analytical services, and tasting services. Her career culminated in her appointment as microbiology consultant in 1993, in which she was responsible for auditing, consulting, training, technical manuals, development and setting of standards and philosophies in microbiology for all the breweries comprising SAB. She holds a B.Sc. in microbiology and chemistry and an Honors degree in microbiology from Rhodes University in Grahamstown and an M.Sc. in fermentation microbiology from the University of the Witwatersrand in Johannesburg. She joined the Siebel Institute of Technology in 1995 as senior brewing consultant and is currently vice president: products and services. She is very involved in the various brewing courses and has responsibility for laboratory services and microbiological media.

Subcommittee members: L. Andersen, F. Barbero, D. Bendiak, M. Bryndilson, J. Carvell, T. Foley, G. Gonzales, G. Hulse, G. Pili, G. Pirez, T. Pugh, K. Smart, R. Stewart, H. Teass, G. Vargas, L. Wallace, C. White, G. White, and C.-L. Dull (ex officio).

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Report of the Publications Committee

The following report was presented to the ASBC Board of Directors at its fall meeting on October 8, 1999, in St. Paul.

The Journal
Issue 57(4) of the Journal contained six papers. Three papers have so far been accepted for Issue 58(1), with a further 14 manuscripts at various stages of the review and revision process. This is an encouraging number, reflecting a year in which we have been able to comfortably meet the editorial deadlines of the ASBC office. Thanks are due to members of the Program Committee, and particularly the moderators, for encouraging submission of papers from the annual meeting. A total of seven manuscripts from the Phoenix meeting (three oral presentations, four posters) have already been submitted to the Journal. Thanks are also due to our reviewers, the Editorial Board, Dr. Alfonso Navarro (for Spanish abstract translation) and to the staff at St. Paul, for the smooth flow of material for the Journal this year.

Millennium reviews on the topics of brewing water, hops, yeast, barley and malt, brewhouse, sensory evaluation, and foam have been successfully solicited. While all authors have promised material between the end of 1999 and the spring of 2000, so far none has risen to the challenge of meeting the October 1999 deadline for Issue 58(1).

Methods of Analysis
An index of the contents of the Methods of Analysis has been prepared using a key word followed by the method(s) that provide the analytical procedures, e.g., Magnesium: Beer-38; Wort-15. [Editor’s note: the index was published in issue no. 4 for 1999.]

A survey of Methods of Analysis reveals 94 methods that have not been revised or reviewed since the 1970s (one not since 1964). These methods should be reviewed before the next supplement is produced. Obsolete methods can be archived, thus making room for new procedures.

Newsletter
Since the last report to the Board of Directors, one issue of the Newsletter has been published. This issue (Vol. 59, no. 3) contained the overview of the annual meeting in Phoenix, the first call for papers (since we’re on an earlier schedule this year for WBC 2000), and an abstract form.

Most of the information for the next issue has been forwarded to the St. Paul office and, according to their staff, the issue should go to print on time.

Report of the Internet Editor
Benchmarking/updating site. The front page has been updated, adding links to the write-ups from the Phoenix workshops and discussion group areas for each of them. Each of the discussion leaders will be asked to make an initial entry and then we can do a broadcast e-mailing to solicit participation. Benchmarking has been done on an informal basis.

Journal. We have a sample Journal up for review and would be interested in comments; see http://www.scisoc.org/asbc/journal/offline/.

Abstracts. Electronic submission of abstracts for WBC 2000 is available at http://www.scisoc.org/wbc2000/asf/top.asp. It was tested extensively at headquarters, passing with flying colors.

Methods. Beer-1, Sampling has been selected for use in developing a demo method of analysis. The intention is to have links to MSDS sheets for the chemicals used and links to the articles referenced, which would include the subcommittee report on the collaborative testing of the method. We would like to include a video clip of someone performing the procedure. Other ideas for inclusion in an e-method are links to vendors and tips on how to perform the method.

Charles W. Bamforth
Chairman, Publications Committee

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International News

Fourth Meeting of the
International Subcommittee for
Isomerized Hop alpha-Acids Standards
The foothills of the Rocky Mountains formed an inspiring setting for the fourth meeting of the International Subcommittee for Isomerised Hop alpha-Acids Standards, held at an elevation of 9000 ft. in Keystone, CO, on September 12, 1999. Six full members (out of a possible 12) were in attendance, plus one proxy member and two guests. Regrettably, only three of the subcommittee’s four parent organizations (ASBC, EBC, IoB, and BCOJ) were represented, neither of the two committee members appointed by the Institute of Brewing having been able to make the trip.

Following acceptance of the secretary’s report of the third (Cannes) meeting, Chairman Richard Wilson (S. S. Steiner, Inc.) turned the meeting’s attention to the continuing study of the purity and stability of small-scale preparations of the proposed new standards for the HPLC analysis of isomerized and reduced isomerized alpha-acids.

Elemental analysis. At the previous meeting, results were presented for the elemental analysis (C, H, O, and N) of small-scale preparations of DCHA-iso-alpha-acids, DCHA-rho-iso-alpha-acids, and crystalline tetrahydroiso-alpha-acids. With one or two exceptions, the data had indicated close agreement with calculated values for the three compounds (and after taking account of the individual cohumulone ratios for each preparation). This meeting was now presented with the data for the fourth standard, DCHA-hexahydroiso-alpha-acids. Agreement was considered excellent for two of the four preparations, but for the other two the oxygen value was not quite in line with expectations. In view of other data indicating a high purity for both these preparations, it was suggested that the incorrect oxygen values were due either to the presence of a small amount of water and/or solvent residue or simply to error in the measurement. (It was noted that the analysis of oxygen content is less accurate than for carbon and hydrogen). After concluding that, in all probability, the four small-scale preparations of DCHA-hexahydroiso-alpha-acids were each fundamentally of high purity, the meeting nevertheless agreed that it would be appropriate to check for the absence of both water and solvent residues in future preparations of the proposed standards.

Storage stability. Attention was next given to the results of the previously organized trial to establish the stability in storage of a selection of the small-scale standards. Duplicate samples of these standards had been separately stored over a period of four months at freezer and ambient temperatures by each of the participating laboratories and then compared against each other by duplicate or triplicate HPLC analyses. Generally, the results were encouraging, although one or two laboratories appeared to have difficulties in obtaining consistent analyses. Of the four standards, DCHA-rho-iso-alpha-acids and DCHA-hexahydroiso-alpha-acids were considered to show no significant signs of differences that might imply instability. Tetrahydroiso alpha-acid samples were reported as possibly unstable by one laboratory that compared its data with the results obtained four months earlier, but in view of a lack of chromatographic evidence of deterioration, it was thought most likely that the apparent loss of "tetra" was due to instrumental causes. Drawing conclusions regarding the stability of DCHA-iso-alpha-acids was hampered by a relative lack of data. Some evidence was seen for a slightly lower content of iso-alpha-acids in the ambient stored sample of one laboratory, but it was not sufficiently large to be considered of definite significance.

Overall, the results of stability testing were considered sufficiently encouraging to continue the trial. A second round of comparative analyses will therefore be conducted in December 1999.

Preparation of the new standards. Agreement to proceed to the bulk preparation of the actual standards themselves was reported at the last meeting. Substantial progress toward achieving the target of producing all four standards was now reported by the three individual committee members who had graciously volunteered to undertake this onerous task.

DCHA-iso-alpha-acids. First, John Paul Maye (Haas Hop Products, Inc., ASBC) reported that he had prepared a batch of material in better yield than previously reported in his recently published paper (J. Am. Soc. Brew. Chem. 57(2):55-59, 1999) by switching to use of acetone as a solvent, but that this preparation had contained a small amount of contamination. Three unidentified compounds had shown up on HPLC analysis. Two of these compounds he suspected to be either cis-iso-alpha-acids or allo-iso-alpha-acids. His proposal to try to improve the purity of his preparation by recrystallization from ethyl acetate, which he knew would, at least, remove the third contaminant, was accepted by the meeting.

Crystalline tetrahydroiso-alpha-acids. Next, Gus Gusinski (Kalsec, Inc., ASBC) reported that he had made substantial progress with the preparation of the tetrahydroiso-alpha-acids standard and was confident that he had enough material to ensure production of the intended quantity of purified material. His problem had been to induce crystallization of the desired mixture of isomers and homologues. He now proposed to blend several batches of pure material having different compositions and then try to induce rapid crystallization in the hope of producing a single, homogeneous material. This was agreed to be a better solution than to attempt to blend together the crystals of these batches. He would also attempt to check the homogeneity by selecting individual crystals for HPLC analysis by a method that separates the isomers and homologues.

DCHA-rho-iso-acids. Lastly, the chairman presented a written report received from Paul Hughes (Brewing Research International, IoB), which outlined the progress made regarding preparation of the DCHA-rho-iso-alpha-acids and DCHA-hexahydroiso-alpha-acids standards. Two batches of the former standard had been prepared, but in each case the quantity produced was insufficient to meet the previously targeted amount. In view of this shortfall, it was agreed that the chairman should contact Dr. Hughes with a view to having these preparations combined and then recrystallized as a single batch.

DCHA-hexahydroiso-alpha-acids. Dr. Hughes’ report also indicated that the DCHA-hexahydroiso-alpha-acids standard was prepared and was now ready for evaluation. It was noted, though, that elemental analysis showed a slightly low result for the oxygen content. Also, since he had not determined the cohumulone ratio of his preparation, it was not known whether the carbon and hydrogen values were correct, although they clearly fell within the absolute limits for DCHA-hexahydroiso-alpha-acids.

The meeting agreed that, once all four preparations were completed, it would be sensible for three or so samples of each to be distributed as appropriate to selected volunteers who had the ability to examine some or all of these preparations by HPLC. The objective would be to have each standard tested using two or more different methods so that the presence of any contaminant substances might be better established and isomer and homologue ratios established where not already known. It was hoped that this exercise could be completed by about mid-December 1999. In the meantime, the bulk standards should be kept at freezer temperature. On the presumption that the interlaboratory examinations by HP contaminant substances might be better established and isomer and homologue ratios established where not already known. It was hoped that this exercise could be completed by about mid-December 1999. In the meantime, the bulk standards should be kept at freezer temperature. On the presumption that the interlaboratory examinations by HPLC do not reveal any obvious defects in these standards, stability trials will then be initiated in which duplicate samples of each will be held at freezer and 30°C temperatures and periodically tested against one another.

It is proposed that the next meeting should be held early in year 2000, a possible location being Las Vegas in mid-January, the designated venue of the next Hop Research Council Meeting and another setting of great character, although in almost every sense rather far removed from the quiet charm of the Keystone Resort before first snowfall.

Richard J. H. Wilson (Chairman)
October 1999

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Proceedings of 27th
EBC Congress Published

The proceedings of the 27th Congress of the European Brewery Convention (Cannes, May 1999) have been published. The proceedings contain the texts of all lectures and posters presented at this congress, 100 contributions in total (882 pages with numerous illustrations, photographs, and diagrams).

The publication has been sent to all registered congress delegates. Additional copies can be ordered from the EBC Secretariat at the price of NLG 125.00 per copy, postage included. Contact: EBC Secretariat, P.O. Box 510, 2380 BB Zoeterwoude, The Netherlands, +31 71 5456047 / 5456614, fax +31 71 5410013.

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