INDUSTRIAL A N D ENGINEERING CHEiWISTRY
May, 1923 POSSIBILITIES OF
PETROLEUM
RESEARCH
The courses in organic chemistry given in most of our universities devote but little time to the petroleum industry. A wellknown textbook on organic chemistry which is used internationally allocates but two of its six hundred pages to the subject of petroleum. The industry needs a systematic study of the chemical composition of petroleum such as has been made of coal tar during the last fifty years. The problems, however,
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are of far greater complexity than those encountered in the investigation of coal tar. Petroleum affords a veritable mine of organic compounds. The magnitude of the industry is such that petroleum research should attract the best trained organic and physical chemists in our universities. Who can ptedict how far reaching both from economic and scientific aspects would be the results of a thorough scientific investigation of this almost virgin field?
T h e Chemist Enters a New Industry’ By H. E. Barnard
of war time was one that made bread stay IVF, or ten thousand years ago a sold. Once it reached the grocer it went primitive baker pounded up a handon to a customer-not back to the shop the ful of cereal grains, wet the mass, next day, if it was unsold. Out of the chaos and baked it on a hot stone. In the course which confronted every baker emerged of centuries he improved his process somean industry with a vision of the value what. He sifted his flours, he arched his of science, of the need of the chemist in hot hearthstone. One day he made up too the shop. T o be sure, the vision was folarge a batch of dough and left some of cused on practical things-on better buying i t unbaked. After the manner of aough, methods, on relative values of materials, it became food for yeasts and fermented. on the fitness of shortenings, sirups, sugar, The next bake was leavened bread, and and salt for their particular purpose. But after years of casual handling of sour dough, fortunately, a chemist once installed in a yeast-raised bread became the basic food laboratory is like a camel’s nose under a of most civilizedlpeople. But after thoutent. Before long he makes the whole sands of years of skilful craftsmanship plant his laboratory. bread baked but a few decades ago was So it has been a t the bakery. To-day, made in the same way as it was in the the paking of bread is a chemical process valley of the Nile when King Tut was put with physical and biological aspects, carinto storage; as it was when the bakers of ried out in huge laboratories filled with Pompeii fled before the descending ashes automatic machinery operating under temof Vesuvius; as it was when our Puritan perature, humidity, and time control. ancestors poached the Indians’ corn cribs H. E. BARNARD And here is where my story begins. and made the first New England johnny Come with me t o this newest of industrial laboratories where a new cake. school of chemists makes its daily bread. All materials are bought Is it safe for me to say here within a stone’s throw of all the world’s history entombed on Yale campus, that baking science on specifications. Flour brands mean nothing except in their ability to produce a good loaf of bread. In other words, such flour has developed more in the past ten year.; than in all the previous years of man? And dare I say that a few baking chemists conforms to the standards of gluten quality, which measures working under little appreciated difficulties have in these short strength; of ash content, which is the gage of milling efficiency; of years overthrown the craft control of a hundred centuries and moisture, which so influences the absorption of water-carrying capacity and which is much cheaper when drawn from a tap a t the built a scientific industry which is doing the baking OF the world bakery than when freighted half-way across a continent in a flour in great laboratoriec, more economically and far better than sack; of color, which means high milling standards, or bleaching, ever before ? To be sure, chemists have helped the miller buy wheat for or both; and of hydrogen-ion content, which some chemists believe his grinding for many years. They have more or less stmidly is a better indication of Hour maturity and adaptability for sucand empirically evaluated flour by weighing ashes and digesting cessful use than high protein or low ash. Milk is an essential ingredient of modern bread. From a proteins. They have given assistance to the brewer and distiller, turned yeast-maker for the baker. But their routine nutritional viewcoint it plays a role second only to that of flour we measure developments in service never unlocked the secrets of fermentation nor solved itself. And every month-for baking chemistry by months now, instead of years-more milk the mystery of gluten. And then came the Great War and days that were wheatless and, so far as the baker was con- is going into the formulas. What kind of milk comes into the cerned, two years crowded with enough grief to make a lifetime stock room? What is its fat content, its acidity, its sugar content? And is the salt worth its cost? Is there any ground miserable. He gave over the operation of his shop to the minions for the salesman’s argument that his particular salt is sweeter of the Food Administration. He learned that bread could be made without flour-or much of it-that there were other ways than competing brands and that the baker can use more of it? Are the diastatic malt sirups really diastatic, and how much? of feeding yeast than with sugar, that lard wasn’t a necessity, that poor materials properly handled would make rather good What about the yeast foods-do they contain talc? And the shortenings-are they true fats or doped mixtures of glycerol, bread. Then, too, he learned the need of making bread that alum, starch, and water? Is the yeast alive and eager to popuwould not get stale over night, for among the hampering rules late the dough batch with its virile progeny, or is it weak and 1 Presented as “The Baker Turns t o t h e Chemist.”
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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 t o 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 a t 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.
