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INDUSTRIAL A N D ENGINEERING CHEMISTRY
unwilling to work? Of course, most of these chemical controls of materials are not new; it is their application in the bakery that commands the chemists’ attention. And when the chemist has checked up his bread ingredients he has the usual line of work still to do-fuel for the ovens, lubricating oils and grease, paints, oils, varnishes, soaps, and washing powders-all old jobs for routine workers. But chemical control goes beyond the analytical laboratory. I mentioned hydrogen-ion determinations on flour samples. What business has a hydrogen ion in a dough batch? Here is where the chemist lays aside his apron and puts on his baker’s cap. Dough is flour, water, salt, yeast, plus milk, sugar, shortenings-all the materials bakers use to make good bread. For centuries the yeast-planted dough was allowed to ferment for hours. Most homemade bread is fermented over night, on a chair by the kitchen stove. Usually a red shawl is thrown over the dough pan. If the night is cool the dough doesn’t rise very well and mother has it in for the miller and buys another brand of flour next time. If the night is hot then the yeast gets busy and lifts the dough mass over the side of the pan. I n good bakery practice the dough comes out of the mixer a t a definite temperature and stays in the fermentation room, with occasional punching to release the imprisoned gases of fermentation, from three to five hours, the time element depending on room temperature and flour or gluten quality and other less influencing conditions. What is the reason for this long fermentation period? Bakers say “It’s to mature the gluten.” What does that mean? It took a chemist to answer a simple question that had remained unanswered from the time the first dough was punched until a few years ago when Jessen Hansen, working under Sorensen a t the Carlsburg Laboratories, began to study hydrogen ions and appliqd them in the measuring of flour and dough acidity. Gluten is an extraordinary material. Flour strength depends on its gluten content, and even more on the character or quality of the gluten. But even the best of glutens will not entangle carbon dioxide in just the way to give ideal texture and grain to the finished loaf unless it is t’reated right-“softened,” the baker says. And it’s the lactic acids and other acids which are formed while the yeast is working away in the dough room which soften gluten. Here enters the chemist again, hydrogen electrode in hand. “Why not,” he says, “find out just how much acid it takes to mature or soften or make just right the gluten of this particular dough batch?” And he does it-and then, instead of training and coddling a trillion or so yeast plants to develop the proper acidity, he puts the calculated amount of lactic acid, or whatever acid salt he finds most useful, into the dough mixer, develops the gluten as best he can by physical means in his highspeed mixer, and shoots the well-mixed dough out of the mixer down to the divider to be cut into uniform sizes for the desired loaf. And it never goes into a dough trough or stops for a moment in the dough room. Four hours taken out of the baking process, and the trough out of the equipment. This isn’t a secret process, not quite. At the American Institute of Baking we have been studying the effect of acids and acid salts on panary fermentation for nearly three years, and our students are taught how to make zo-called “quick” or lactic acid doughs. But the process is just coming into bakery practice. I recently asked the technical head of one great baking company how he proposed to teach his bakers how to make hydrogen-ion determinations and apply them to the doughs in the form of cubic centimeters of acid or grams of salts, “That’s easy,” he said, “we shall not have any bakers in the shop.” And when I asked him who was going to make the bread he said, “The shop chemist, of course.” Well, that seems to be about the end of my story. The chemist has taken over the steel mills, the glass factory, the rubber works-every industry which fabricates raw material into finished products for the benefit of mankind. And now the baker has
Vol. 15, No. 5
gone the way of the butcher and candlestick maker. Bread is no longer a work of art-guess work, a t that-but an achievement of science, built of selected materials combined by controlled processes, with no waste of materials in the fermentation process and no possibility of a poor product coming out of the oven. There is need of chemists for the baking industry-a greater need perhaps than in any other industry-but to the science of the classroom and laboratory must be added the practice of shop operation. And greater even than the need of chemists in the bakery is the need for research workers in a score oi vital problems of the wheat farmer, the miller, the yeast maker, the malt sirup maker, and in every field which supplies the needs of the baking industry, the most important of all food industries and still the least informed. While statistics are hard to secure and harder to listen to, it is of some interest that 60,000.000 barrels of flour are being turned to bread this year; that 33,000 bakers are hard at the task, most of them still using shoulder muscles instead of machines and craft rule-of-thumb practice instead of scientific Formulas; that the value of the product is up in the billions; that the industry which ranked seventeenth in 1900 is now seventh in magnitude and growing by leaps and bounds; that home baking is passing as surely as home weaving or home brewing: perhaps more so, and that the latest baker’s loaf is so perfectly balanced and built up that all it is necessary to take into the wilderness is a loaf of bread and a jug of water to satisfy at least the nutritive needs of mankind. The complete food in pill or capsule has long been talked of. Now, our chemists have brought it to pass in the form of bread. Numerous generations of mice and rats attest its completeness by increasing their progeny with each new generation. Speculation as to the effect this astonishing loaf will have on the Malthusian doctrine is not as yet in order, for the life cycle of the human family is markedly different from that of the mice and rats who are willingly serving as subjects in these nutritional studies. In the Nutrition Laboratories of the American Institute of Baking, we have demonstrated the great nutritional advantages of the use of milk in bread formulas by feeding experiments on white rats. The average American may little need such a complete food in a single article of diet. It is worth noting, however, that chemists a t the bakery can and are producing a complete ration, and that after these many years of effort the baker’s oven is giving us bread that is superior in craftsmanship, in scientific uniformity, and in nutritive value to the homemade loaf. I cannot let this opportunity pass without telling of the need a t the American Institute of Baking for research fellows. Several fellowships are available for chemists who may wish to make cereal and baking chemistry their life’s work, and, for other chemists who may wish to fit themselves for positions in the modern bakery, our School of Baking offers short courses which are proving entirely practical. Our only sorrow is our inability to meet the demand for chemists with the special knowledge required of them in the bakery.
Complimentary Luncheon Following the dedication of the Sterling Chemistry Laboratory, Yale University entertained specially invited guests, ladies, and members of the AMERICAN CHEMICAL SOCIETY a t luncheon in the University Dining Hall. At the conclusion of the luncheon, before introducing the speakers, President Angel1 briefly traced the history of chemistry at Yale. He then introduced T. W. Richards, of Harvard University, who referred to the importance of chemistry t o medicine, agriculture, hygiene, and industry in peace even more than in war. The following distinguished foreign representatives were then introduced and spoke in a delightful vein, congratulating America upon the rapid progress of science here; W. Lash Miller, of the University of Toronto; Guiseppe Bruni, of the University of Milan; G. Urbain, of The Sorbonne; A. F. Holleman, of the University of Amsterdam; T.Svedberg, of the University of Upsala, Sweden; F. G. Donnan, of the University of London; and J. C. Irvine, of the University of St. Andrews, Scotland.
