Molecular Sciences Bldg 21, James Cook University,
Townsville, 4811, Queensland, Australia
Telephone: 61-7-4781 6265 Fax: 61-7-4781 6078
If I told you that we're now going to talk about the science of beer, there's a fair chance you'll infer straight away that it's time to be flippant, make a few puns, go in for some drollery. In fact the science of beer, you'll be pleased to know, helped revolutionise chemistry and the understanding of the molecules which make life possible.
For such an insight we must thank Dr Alan Baxter, who's head of the Autoimmunity Research Group at the Centenary Institute in Sydney, and author of the book Germ Warfare: Breakthroughs in Immunology which we talked about last year. And Alan Baxter begins the tale with one of the greatest names in the history of science.
Today, Louis Pasteur's name is usually associated with milk. After all, it appears on every carton and bottle of the stuff. But his major contribution to Australian society lies not so much in the milk bar, as in the public bar. Since he disliked the taste of beer, the basis for his interest in it is somewhat obscure, but it makes an interesting story and is probably worth telling.
Pasteur's reputation as a chemist had been established when he discovered that some organic molecules exist in two different orientations, or isoforms, related to each other by reflective symmetry. Since only one of these two orientations ever occurs in plants and animals, this led him to propose that chemical orientation provided a criterion to distinguish between living organisms and the inert inorganic world. On this basis, he did not believe in the spontaneous generation of life, and his fiery opposition to the idea led him to be regarded as something of an expert on biological matters. He became a free-lance scientific consultant advising on a range of agricultural and industrial problems. In doing so, he greatly enhanced his reputation by identifying the organisms that spoiled wine and vinegar, and those that killed silk worms - discoveries that made a significant impact on the French economy.
But Pasteur's principal interests lay with basic science, not industry. 'There is no such thing as applied sciences,' he said, 'only applications of science.' Seeking to establish a publicly funded research laboratory at his university, the Ecole Normale, he wrote to emperor Napoleon III, 'I wish for a spacious laboratory where experiments can be performed conveniently without danger to public health. Some of my current experiments relate to the transformation of organic matter after death and ... these studies can only proceed if a fully equipped laboratory is set up. The time has come to free the experimental sciences from the fetters of poverty.'
The emperor's support was quickly gained. By the end of 1867, plans had been drawn up and the ground breaking for the construction of the new laboratory took place in the summer of 1868. Pasteur monitored the builders' daily progress from the dining room window of his university accommodation across the rue d'Ulm from the work site.
Louis Pasteur felt unwell throughout most of the19th October of that year. Despite an oppressive fatigue and a fleeting prickling sensation down his left side, he attended a meeting of the Academy of Sciences and fulfilled the rest of his commitments for the day. On his return home, he excused himself from dinner and retired early. That evening he was felled by a massive cerebral haemorrhage in which he lost the power of speech and the use of his left limbs. Doctors were called and leeches applied.
Of those that rushed to his bedside, one of the first to reach him was his dear friend, Pierre-Augustin Bertin. Pasteur and Bertin had met as students, and their professional paths had intersected more than once since. Bertin, as the current Head of Scientific Studies at the university, was technically Pasteur's boss, but his desolation at the disaster than had befallen his colleague betrayed a much closer relationship.
Madame Pasteur and Monsieur Bertin conspired to nurture the invalid through his convalescence. Gradually Pasteur recovered somewhat. His speech returned first, and then his power of thought. His body healed more slowly, and he never regained the use of his left hand. Every day, as he lay in his bed, he asked visitors for news of the construction of his new laboratory. And every day, under strict instruction, his visitors gave him vaguely unsatisfying responses. Finally, Pasteur dragged himself through to the dining room window, and hauled himself up to his feet. The desperate effect of what he saw was as great an upset as the stroke itself, for within an hour of news of his illness, all work on the laboratory had stopped dead.
His raging bitterness was relayed through a well-connected visitor and he quickly received an apology from the emperor and an assurance that the project would be completed. But work was again interrupted in July 1870 by Germany's invasion of France during the Franco-Prussian War. By October, the Germans had captured the Emperor and Paris was besieged. Furthermore, Pasteur's only son Jean-Baptiste had enlisted and was now gravely ill with typhoid.
Pasteur’s anguish at the national crisis was magnified by the loss of his laboratory and the threat to his son's life. The war had jeopardised everything he cared about - Nation, Family and Science - and he was physically incapable of fighting back. This overwhelming feeling of impotence left him with an obsessive hatred of Germans and their nation and, by the end of the war, Pasteur had formulated a plan to avenge his nation’s honour.
At the time, although Germany had become the world leader in industrial chemistry, her main export was beer. Indeed, as part of the reparations demanded of France, Germany had subsumed Alsace and Lorraine, where hops were the primary crop and much of France's own beer production had been based. German beer outsold local brews throughout most of central Europe because it tasted better and kept longer, and its continued sale in France irritated Pasteur intensely. He planned to destroy Germany’s primary export market by developing the world's best beer in France, a brew he dubbed 'the beer of revenge'.
Beer is produced by fermenting water in which malted barley has been steeped. The carbon dioxide that gives beer its head is released by the yeast as a by-product of fermentation. Hop flowers are added prior to fermentation, because their aromatic oils act as a preservative and add to the taste of the finished product. Originally, all beers were dark and heavy, similar to the porters, stouts and brown ales of Britain. The major advance made by Germany in the 1860s was to develop strains of yeast that maintained their activity at temperatures near freezing. Fermentation achieved at such low temperatures proceeded so slowly that the beer had to be cellared over the whole winter instead of for just a few weeks. Furthermore, the yeast, instead of being buoyed to the top of the brew by the carbon dioxide produced (called 'top fermentation'), sank to the bottom of the barrels and contributed little to the taste of the product. This was called 'bottom fermentation', or 'lagering', and the resulting lager beers were pale straw coloured, light in flavour and body, and kept extraordinarily well.
Pasteur correctly surmised that the primary reason for beer spoilage was the presence of contaminating organisms. He quickly identified those most commonly spoiling brewery yeast samples and developed methods for excluding them from large-scale fermentations. He also developed new strains of heat-stable yeast that acted more rapidly without significantly contributing to the taste of the beer.
Pasteur had by this time returned to his old haunt at the Ecole Normale. He bought a brewery kettle and installed a fermentation vat in the basement of the as yet unfinished laboratory complex nearby. Bertin’s interest in Pasteur's experimental progress increased dramatically, betraying a fond familiarity with the subject under scrutiny. Bertin had developed a fancy for fine ales when he had worked in Strasbourg and a strange collaboration developed between the two men. Bertin's sober responsibility was to steadily drink his way through Pasteur's experimental results in order to provide a critical appraisal of each batch. Bertin’s high-spirited laughter and good humour did much to enliven the laboratory, and he pointed out to Pasteur more than once, that there is much more to good beer than just keeping it free from infection. "First make me a good bock,' he said, 'and then you can tell me about it!"
Pasteur travelled widely throughout Europe, demonstrating the key aspects of his methods to commercial brewers. The Whitbread brewery in Britain and the Carlsberg brewery in Denmark still attribute their success to visits by Pasteur in the 1870's. An even greater influence was attained on publication of his book 'Studies on Beer', which immediately became the essential brewer’s manual.
A brilliant young Belgian brewer, Auguste de Bavay, met Pasteur on one of his trips and adopted his methods before emigrating to Melbourne, where he was employed at the Victoria Parade Brewery. Because of the warmer temperatures in Australia, de Bavay had to adapt Pasteur's methods to top fermentation. To protect against spoilage, he added greater amounts of hops, and fermented to a higher alcohol content. The highly fertile soils and plentiful sunshine resulted in increased levels of protein in the barley, which caused clouding of the beer, so de Bavay replaced some of the barley malt with cane sugar. The resulting beer was that now characteristic of Australia: light in colour and body, but tasting strongly of bitter hops. This style, although correctly described as a 'bitter' in Australia, is usually mistaken for a lager in Britain.
de Bavay was quickly promoted to chief brewer at Fosters, a position he held from 1894 to 1904. For much of this time, he also acted as bacteriologist for the University of Melbourne and used the influence gained from that role to fight for improvements in the quality of the Melbourne water supply. In 1889, his denouncement of the city's fire plugs, claiming that they admitted sewerage and typhoid bacilli into the domestic water supply, resulted in a royal commission and the eventual removal of the devices. Although his primary interest was to protect the product of the brewery from infection, his efforts did much to protect the city's population likewise.
And what of Pasteur? Well, he too saw the parallel between the infection of an ale and human disease. 'Seeing that beer and wine undergo profound alterations because these liquids have given shelter to microscopic organisms...' he wrote, 'how can one help being obsessed by the thought that phenomena of the same kind can and must sometimes occur in humans and animals.' It was this analogy that drove him on to study cholera, anthrax, erysipelas and finally rabies, culminating in the development of the rabies vaccine.
His strategy of revenge was also very successful. Indeed, so successful
was it, that to this day, even though some German beers are widely
as being among the best in the world, very little is exported. The
is that the German breweries rendered idle by Pasteur's strategy were
to manufacture acetone for cordite production. Thus Pasteur's vengeance
indirectly helped to equip Germany for their attack on France in the
The paradoxes of history. Alan Baxter, from the Centenary Institute in Sydney. His book, 'Germ Warfare' which is about immunology, not Saddam Hussein, is published here by Allen & Unwin.
Next week, Ockham's Razor comes from Newcastle, where Professor Colin Keay is convinced nuclear technology is a very good idea, despite its press. I'm Robyn Williams.
'The Beer of Revenge' is © Alan G Baxter 2000
Autoimmunity Research Group, Centenary Institute of Cancer Medicine and Cell Biology, Key words: Autoimmune diabetes, Type 1 diabetes mellitus, childhood diabetes, lupus, systemic lupus erythematosus, hemolytic anaemia, hemolytic anemia, Coombs' test, antinuclear antibodies, renal failure, glomerulonephritis, gastritis, type A gastritis, pernicious anemia, immunology, popular science, biology.