XII. CHEMICAL PROBLEMS OF THE CANE SUGAR AND MOLASSES INDUSTRY C. F.WALTON, JR.,CARBOHYDRAI*: DIVISION, BUREAUOF C ~ M I S T R &YSOILS, U. S. DEPARTMENT OF AGRIC~.TURE, WASHINGTON. D. C.
Cane sugar and molasses production of the continental United States is at present confined principally to Louisiana and Florida. Sugar cane sirup also is made in these states, and in addition is manufactured in Georgia, Alabama, Mississippi, and Texas. A number of chemical problems exist in the manufacture of cane sugar, simp, and molasses in the United States. These problems are in addition to those of the sugarrdning industry.
Direct White Sugar and Molasses Manufacture The chemical problems of domestic manufacturers are closely correlated with present economic conditions. Low prices, resulting from world overproduction of sugar, make it imperative for high cost domestic manufacturers to have tariff protection, and tend to bring about various consolidations. Louisiana, with an adequate ta*, could continue to operate as for many years past on the individual plantation basis, with a large number of factories individually operated and products marketed by each plantation without regard to a predetermined and unified plan. The prevailing opinion, however, favors a more progressive policy. Raw sugar could, if desired, be made the principal product of the domestic cane-sugar industry. Raw sugar, however, is just raw sugar, and the price for it in Louisiana is the same as on the New York exchange. Louisiana in manufacturing raw sugar must compete with Cuba. For many years certain products which may be called "specialties" have been manufactured in Louisiana. Direct consumption sugar of various grades (not char refined) and commercial sirup and molasses have frequently brought a larger net return than raw sugar. But the market for such specialties has been limited. Grades of "yellow clarified," "plantation white," and "plantation granulated" sugar (made by chemical clarification rather than by char refinery practice) have varied greatly in quality, as also have sirup and commercial molasses (other than blackstrap). Failure to produce uniform grades has tended to limit the demand. Moreover, while both domestic beet sugar and refined cane sugar have been steadily improved in quality, the direct oonsumption of Louisiana sugar, made by the sulfitation process, has failed to keep pace with modem progress. To improve the quality and uniformity of these Louisiana 2326
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products, thereby making for greater salability and a somewhat larger net return than results from the manufacture of raw sugar, is a chemical problem, essentially one in the field of colloid chemistry. It includes the investigation of, and the attempt to improve, existing methods of cane juice clarification. As the growing of sugar cane in Louisiana has recently been put on a more stable basis, owing to the introduction of new and hardier cane varieties, and as sugar production has correspondingly increased, the balance between supply and demand for those specialties which Louisiana is especially well qualified to supply must be restored to enable manufacturers to take advantage of the differential which should exist between specialties and raw sugar. During the past year, for example, more highgrade molasses was made than was in demand a t a fair price; consequently, the price dropped to such a figure that approximately as large a return could have been secured by many of these factories by making raw sugar. The remedy for such a condition is a voluntary consolidation of interests, to plan ahead each year for the manufacture in the best-equipped and officially designated factories of only as much high-grade molasses as can be advantageously marketed. The managers of only a relatively few large companies could bargain collectively at the beginning of each season with molasses buyers, thus insuring a fair price and limited output. Similarly, other factories would be properly designed to make either sirup, white sugar, or raw sugar and blackstrap molasses, and to make these products most efficiently. At present the design and equipment of domestic cane sugar factories, taken collectively, are not such that the manufacture of any one specialty can be limited or expanded at will without some sacrifice. Louisiana interests badly need consolidation and a definite guiding plan. At present the chemist and chemical engineer are greatly handicapped in selecting the most urgent practical problems, and later in applying their findings to proper advantage. Technically speaking, the chemist knows that some kind of improvement is badly needed, but he has great difficulty in ascertaining just what it should be. The economic phases of the domestic sugar-cane industry have been considered at some length because they are so closely correlated with the manufacturing or chemical problem. The production of direct consumption white sugar and high-grade molasses, for instance, can doubtless be enlarged and made more profitable by chemical research to improve quality, uniformity, and yield per ton of cane; but to make real progress along this line there should be a comprehensive idea of economic factors, careful planning, and a close-knit organization of the manufacturers to stabilize grades and quantity of production. With proper organization and co&dination of purpose, a steady and even rapid
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chemical progress can be expected in the improvement of quality, standardization of grades, and increased factory efficiency. Sugar Manufactnre from Deteriorated Cane Owing to the seasonal freezes which usually occur in either November or December in Louisiana, an important chemical problem exists in the development of the best method of manufacture for frozen and deteriorated cane. If sugar cane is frozen, and has to remain in the field for some time before delivery to the mill, the juice acidity increases rather rapidly and the percentage of sucrose decreases. The e5cient manufacture of any product from deteriorated cane becomes progressively more difficult. In time such cane becomes worthless for milliig. A comprehensive study of the chemical and enzymic changes in sugar cane after a freeze is necessary, the results of such an investigation to be applied subsequently in determining the best method of handling the crop in the field to minimize loss of sucrose. Whether to windrow before or after a freeze, which varieties of cane to mill first, what is the rate of decomposition under different conditions of storage, and other similar problems are questions best answered by chemical work done in close cooperation with the field organization. Clarification of the juice from deteriorated cane is likewise a problem. This kind of chemical work will supply the field and factory managers with the necessary facts by which they can decide, without guess work, what means to take to insure "saving the crop." They may decide it to be wise to provide a factor of safety great enough to save the entire crop during the most unfavorable harvesting season on record. To do this would mean, possibly, improving transportation facilities for the larger factories, a continuation perhaps of certain smaller factories strategically located, an earlier start of the manufacturing season, and an improved field organization so managed as to keep working in the field, rain or shine, with the purpose of keeping the factory supplied with cane regardless of the weather. It would be advisable also to develop an improved process for clarification of juice from deteriorated cane, possibly to provide more ample settling capacity, vacuum pans, etc., to enable the proper handling of "slow working" juices. The wisdom of incurring such additional operating expense can best be judged by chemical data on which to figure operating costs and the yields of sucrose resulting from the various possible ways and means of improving harvesting and production methods. By-products The development of by-products is one of the modern ways of making more profit in any industry. The sugar-cane industry is no exception. Building and insulating board is now manufactured commercially from the
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fiber of the cane stalk, which was formerly burned as bagasse under the boilers. The price paid for bagasse is still based on the actual cost of replacing it with fuel oil or natural gas. More recently a small quantity of bagasse has been used for the manufacture of artifiaal silk. I t would help the sugar manufacturer to dispose of his bagasse more profitably if the chemist could develop still other uses for this material. Final, or blackstrap, molasses is now prinapally used in the manufacture of industrial alcohol and cattle feeds. Methods have been developed for desugarizing molasses, but this disposal of sugar-cane molasses is not profitable with the present prices of sugar and molasses. If the chemist can find other uses for blackstrap molasses, such additional demand will be advantageous. In other countries cane wax has been extracted from the filter-pressmuds. In this country the non-sugar solids removed by clarification of the juice and sirup are taken from the presses to the fields for use as fertilizer. The chemist may find a more profitable use for this low-grade by-product. Such problems as improved analytical and factory control methods are always present in all industries using chemical control. In cane sugar factories, progress along these lines is desired and coustautly expected.
