Sept., 1922
T H E JOURNAL OF INDUSTRIAL A N D ENGINEERING CHEMISTRY
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Chemistry as an Aid to t h e Tobacco Industry By A. L. Chesley CHEMIST, THEAWERICAN TOBACCO Co., NEWYORK, N. Y.
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T IS OFTEN asked, “What need has the tobacco indus- color is desired; it also increases the chlorine content of the try for a chemist?” Every process, every treatment that leaf. tobacco undergoes, from the time the seed is planted After the “topping” process, which means the cutting off until the cured and aged tobacco is ready for the consumer, of the flower bud, the leaves become thicker, heavier, brittle, is based on chemical reactions and changes. A few of these and begin to drools. This is also a sign of maturity. The are understood, but in most cases neither Eeason for it has bee; shown to bethat the the cause nor effect is known. For inplant food which ordinarily would be carstance, what causes Turkish tobacco grown ried into the flower and seeds is forced into in Turkey to have an entirely different the leaf. Thus chemistry has explained aroma from tobacco grown in the same why “topping” produces a larger and betway and from the same seed in California? ter bodied leaf than by allowing the plant Why will not plants grown in Cuba, and to pursue its natural course. transplanted into Florida with Cuban soil In the curing of most plants, the only around the roots, mature into the same object is to bring about such a condition quality of leaf as if they had matured in that the material can be stored until the Cuba? Why are Sumatra wrappers grown next crop without deteriorating. I n the in Florida thicker and heavier bodied than curing of tobacco, besides the storage those grown in Sumatra? Could these qualities, there are more important objects questions be answered it would be a great to be attained, production of a good aroma boon to the tobacco industry; but because and light color, fixing the color, and securtobacco is such a complex product of naing a tough and supple leaf. Curing was ture, and so many things, such as color, formerly accomplished by building a fire aroma, burning properties, body, toughunderneath the leaves and allowing the ness, and pliability, have a direct bearing smoke to escape through them. To-day on the quality of the leaf and the sale of only export tobacco is cured in this manthe manufactured article, chemists have ner. Tobacco for home consumption is not been able t o make the great strides cured by evaporating the moisture in the A. L. CHESLEY in aiding, controlling, and improving the plant juices in such a manner that the life various primary processes that they have in other industries. processes of the plant will continue to function until certain The main reason for this is because the intricate chemical food materials have been consumed and other compounds reactions carried on by the plant are but little understood, produced in their place. I n some methods of curing the and there are many variables to contend with. sugars remain and in others they disappear; citric, malic, and oxalic acids are produced from the sugars; later these are TOBACCO GROWERS’ PROBLEMS changed to a large extent into carbon dioxide and water; But let us see what the chemist has accomplished. If citric acid is not as readily oxidized during this change as the we take up the primary processes, we find many instances other two. In another method the acetic acid increases six where he has been of great aid to progress in this industry. times and the nitric acid decreases one-half. In another His knowledge was needed in solving the fertilizer problem. there is a transmigration of the salts through the veins to the The ratio of ammonia, phosphoric acid, and potash in the midrib and into the stalk. fertilizer is of great importance and must be controlled to You have often seen a cigarette sputter while held in the suit the type of tobacco raised far more closely than in grow- hand, and have probably thought it due to added potassium ing most crops. Too much plant food is as injurious as too nitrate. This is not so, but is due to a crystal of potassium little. Lack of ammonia causes the growth to be backward, nitrate which occurs naturally in the tobacco. As much as and to obtain a good quality the growth must be rapid and 2 per cent of potassium nitrate is found along the midrib. uninterrupted. Too much ammonia makes it very strong, Years ago it was the custom to add potassium nitrate to dark in color, and increases the nicotine content. A fertilizer improve leaf of poor burning quality. To-day this is made deficient in potash or containing chlorides will cause the to- unnecessary by the use of proper fertilizers and control of the bacco i o be of poor burning quality. While an excess of growth and curing of the leaf. sulfates is harmful, they are not as injurious as chlorides. While many of the changes that take place are known, it has A large cigar company has just issued instructions to its not been possible to induce them by artificial means or even to representatives in Porto Rico to reduce the amount of am- shorten the time necessary for them to take place. Several monia in the fertilizer in order to obtain leaf of lighter color. processes have been patented, for which startling claims have The custom was to use lime with the fertilizer to improve the been made, but they have proved to be of no value. As a rule burning quality. It was found, however, that alkaline they only injured the tobacco so it was not suitable for use. materials create conditions favorable to certain fungus disIt has been possible to aid by controlling the temperature eases, especially root rot. To-day this class of materials and humidity so that those conditions which best suit the is not used except when it is impossible to obtain the desired production of these changes may be obtained under adverse quality in any other way. The source of the fertilizer has a climatic conditions. To-day all large growers have modern great deal to do with the various qualities of the leaf. Stable curing barns so they can keep the temperature in the barn manure, for instance, should not be used where a very light slightly higher than the outside temperature, thus increasing
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THE JOURNAL OF I N D UXTRIAL AND ENGINEERING CHEMIXTRY
the moisture absorptive power of the air. On the other hand, as the changes during curing are chemical, the air must not have too great a drying power or the changes will not take place. PROTECTION OF BRANDS The chemist in the tobacco industry is concerned with everything entering into the manufacture of the various brands and the placing of them upon the market, but the tobacco itself. The main assets of a tobacco concern are its brands; therefore, one of his chief duties is to keep u p the standard of those brands. There is probably nothing in which slight changes are so noticeable as in tobacco smoke. The manufacturer has learned by experience, and often to the detriment of his profits, that he must keep his brands uniform in every way from day to day, and it is along this line that the chemist is of the greatest value. It is here where the greatest progress has been made. Many supplies are peculiar to the industry itself. For some of them no standards had been set. Even the suppliers, in some instances, had no knowledge of the quality of their products. To-day, in our company, every supply must first pass the test of quality before it can be purchased. Even the suppliers themselves have to a certain extent been investigated. Preference is often given to the one who has proved that his quality can always be depended upon, even when his price is slightly higher and another’s sample analyzes equally as good. Thus, after the first few years, supplies below standard decreased; so that one year but 30 samples were received that were below requirements, and most of these were rejected before purchase. Suppliers learned that the quality of their goods was being watched and took care to see that their goods met our specifications. Since the war there has been quite an increase due principally to competition and to stocks bought for speculation.
FADING OF LITHOGRAPHS Probably the largest single piece of research undertaken during the last two years was on the fading of lithographs. At the time the matter was agitated it caused quite a furor among ink manufacturers. They claimed there was no need of it, that their inks were permanent and they would guarantee them, They would not, however, back their guarantee with cold cash, using the argument that they did not have control of the paste, or that the posters might be exposed where fumes would cause fading. A concern had suffered because of the fading quality of the ink used on its lithographs. It received reimbursement for the posters but not for the posting. A national posting is for 30 days and costs about $275,000, the posters costing about $25,000. Obtaining reimbursement for the cost of the posters is not much satisfaction when the entire outlay is considered. As no concern would guarantee us against this loss, it became necessary to find some way to protect ourselves. We made over 1000 tests on a billboard, through the months of June, July, and August, with inks of known composition, and compared the results with tests made on the Fade-0-RIeter. As the humidity and temperature around New York City is the most trying on lithograph inks, it was only necessary to find the equivalent for this section in order to protect ourselves all over the United States. It was found that 50 hrs. on the Fade-0-Meter were equivalent to 30 days on a billboard having a southern exposure for these months in this vicinity, and would protect us in practically every instance. It was also found in these tests that a color would have different fading qualities according to the other ingredients used with it, and that some supposedly fast inks would fade. The Fade-0-Meter Company has since published results showing that 40 hrs. are equivalent to 30 days’ posting in Chicago.
Vol. 14, KO. 9
CIGARETTE PAPER Outside of tobacco, the most important article used in cigarette manufacture is the paper. It must be odorless, tasteless, of sufficient opaqueness, and burn evenly with the tobacco. This paper, except a small quantity used for special purposes, is made of pure linen stock and an inert filler, calcium carbonate. The latter is necessary to give the necessary whiteness to the paper, prevent air being drawn through it, and make it burn readily. During the war there was a great deal of trouble with poor burning paper. Very often cigarettes which would not stay lighted would be found on the market. The trouble was found to be in the purity of the filler. It really should not be called an impurity as it had always been allowed, and some manufacturers claimed it to be beneficial. It was found, however, that in the amounts in which it was occurring it had a fireproofing action which varied according to the type of tobacco in the cigarette. Tests were immediately made in all factories on every reel of paper. One factory alone rejected 1000 reels, which would have made 40,000,000 cigarettes. The effect on the brands of this large amount of bad burning cigarettes can be imagined. At about the same time cigarettes having a foreign odor appeared on the market. This odor was also located in the paper, and tests were installed in the factories to prevent any such paper being used. The cause was not determined until some time later when it was traced to the bleach used in the cleaning of the linen stock. Almost all cigarette paper comes from France, and the manufacturer, because of war conditions, had to find a new supply of bleach. This he obtained from Switzerland where spring water was used in its manufacture. This water contained a trace of iodine compounds which caused the trouble. It was not possible to get an iodine reaction in the paper itself, the quantity present was so slight, yet the odor was noticeable in the smoke. In times past, manufacturers of cigarette paper, it is Raid, have used potassium nitrate to aid the burning quality. This is absolutely unnecessary when the paper is properly manufactured, and the right quality of stock is used. A cigarette paper containing potassium nitrate indicates that the manufacturer does not know how to control his process or he is trying to cover up a case of poor manufacture. It is useless to test paper which has been taken from cigarettes for nitrates, as nitrates occur naturally in tobacco and the paper often absorbs a sufficient quantity to give the reaction. Because of these war troubles a great deal of work was done, and is still being done, on cigarette paper. As a result there are but one or two manufacturers who make a paper considered satisfactory for our use. Some time ago, a manufacturer wrote that he was glad he had a t last got the quality of his paper so that it satisfied the chemical department. ADHESIVES The matter of adhesives is a very important one with a tobacco concern, as they have to be of many qualities and kinds. Each purpose and each type of machine require an adhesive of special properties. Two of the most important properties are that they shall be odorless and transparent. A short time ago the concern furnishing paste used in corktipping cigarettes went out of business. No other concern was making this paste as this concern had developed it for this special purpose. This paste had already been analyzed and by modifying a paste used for another purpose our needs were immediately met. I n another instance the revenue stamps were not adhering properly to the cigarette shells. It was found that because of the printing ink used, the paste did not contain enough water to penetrate the surface of the shell before it had dried. For sealing shipping containers, research
Sept., 1922
THE JOURNAL OF INDUSTRIAL A N D ENGINEERING CHEMISTRY
was carried out on various grades of sodium silicate on the market. It was found we could get a better bond, increase the speed of the men, and use less silicate by getting the right kind. In some instances there was a difference of 50 per cent in the number of containers sealed by two different silicates. When the last railroad strike occurred, a supply of paste for use in attaching labels at one of our southern factories was delayed. The lack of this paste meant shutting down the entire factory. A formula had previously been worked out for a similar paste, but it was not being used. This factory was able to run the entire time by getting in its raw materials by parcel post and making its own paste. While the actual value of this cannot be figured in dollars and cents, the loss a shutdown would have entailed will probably cover the cost of the department for some time. This factory is now making its own paste at a saving of about $7500 a year. The savings on adhesives alone since the chemical department has been in existence, figured on an accumulative basis, are approximately $75,000. I n order to better protect cigarettes from drying out, a layer of paraffin was used for pasting the paper to the tinfoil. During the summer months complaints were received about cigarettes being stained. It was found that although the melting point of the paraffinwas 130”F.,if kept at 119”F., it would become fluid enough to soak through the paper. Furthermore, a container placed in the sun would absorb sufficient, heat, so that, with a temperature of 89” F. in the open air, the temperature in the container reached 122” F. It was further found that in a mixture of two paraffins of different melting points, the staining point was about six degrees below the lower melting point. CONTROL OF MOISTURE CONTEXT Up to two years ago we were receiving a material which varied very greatly in the amount of moisture it contained, mechanical impurities, and condition in which it was received. As a result there was a loss of 15 to 20 per cent on all that was bought. The handling of the material was costly. It was very hard to tell whether we were using the same quantity each time or not, and getting the material out of the containers was difficult. Often it would be fermented and have to be thrown away or would have a scorched taste because the evaporation had not been properly controlled. It was claimed that we could not obtain this material in any other way, inasmuch as it would be impossible to educate the producers, who are mostly small farmers. This material is maple sugar, many pounds of which are used each year by the tobacco industry. Our present specifications call for it to be put up in boxes of 60 lbs. each, lined with paraffined paper, to contain not over 7 per cent of moisture and not more than 6 per cent of invert sugar. The amount of invert sugar is a guide as to what temperature the evaporation has been carried, and as to whether the sap used was fresh or fermented. To be sure, we have to pay a higher price but the quality js worth the increased cost. Few materials are so affected by changes of humidity as tobacco. It will take up or give off moisture very readily. The writer has found that if conditions are favorable, tobacco will take on moisture until it contains as much as 30 per cent. Being high in nitrogenous matters, when the moisture content becomes too high it is apt to mold. It is therefore necessary for tobacco concerns to manufacture their goods under absolutely sanitary conditions to prevent a very large loss in returned goods. It has been found necessary in one or two instances, especially in cigar factories, to close the factory and fumigate with formaldehyde to get rid of the mold spores. To-day probably 99 per cent of the tobacco which becomes moldy is through no fault of manufacture, but because of the
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conditions in small retail stores. Yet, the manufacturer, in order to protect his brands, must keep moldy goods off the market and suffer the loss for which he is not to blame. He has, however, made wonderful progress in this respect, when it is considered that the state of Texas probably accounts for 25 per cent of the moldy tobacco of the whole United States and the states bordering the Gulf of Rlexico account for 75 per cent. Last fall the writer saw a box of tobacco manufactured in 1908, and although this had been in a retail dealer’s store for twelve years the tobacco was in excellent condition. During the first three months of this year, cigarettes manufactured during 1921 showed but one moldy out of every 140,000 manufactured. When it is considered that some of these had been on the market for fourteen months, the extreme care used in manufacture and packing is evident. The manufacturer who does not understand thoroughly the necessity of the utmost cleanliness in his plants will find himself in all kinds of trouble.
. . . . . . During the war we were shut off from the source of supply of a very important material. A similar product was native to America but had never been gathered. On testing out the American variety it was found to be perfectly suitable, and, if anything, better suited to our needs. Up to the present time we have been able to obtain all we need from American sources, and unless something unforeseen happens shall not return to the use of the foreign variety. Thus the chemist has his place in the tobacco industry, and has assisted in its forward progress the same as he has elsewhere. Although he is not yet able to be of the assistance he would like to be in the maturing, curing, aging, and preparation of tobacco for the machines, because of his limited understanding of plant processes, there are problems arising every day where his services are of value. He cannot introduce the characteristics of one tobacco into another, make good burning tobacco out of poor, or light colored out of dark, for the reason that it is impossible to dissolve out one substance without removing others which are necessary, and he cannot add something to tobacco in the same way that nature does. The chemist has been of great assistance to the farmer in the control of his soil, fertilizer, and insect pests, and rotation of his crops to obtain the greatest yield. But if a manufacturer wants more Turkish he must import more; Virginia tobacco cannot be changed into Burley, or Burley into Perique. If a mellow tobacco is wanted it must age for from two to three years. Perhaps in the future the chemists will solve these problems. Royalties received from the production of minerals on leased public lands are becoming quite an important item of Federal revenue. The Bureau of Mines reports receipts totaling $5,766,507 to June 30, 1922, from the production of oil, gas, and gasoline in the states of Wyoming, Montana, and California. Oil and gas royalties are now being reported in excess of half a million dollars per month, receipts for June 1922 amounting to $565,199. Royalties from the production of oil, amounting to $550,708, constitute the bulk of the June 1922 receipts. Royalties on gas amounted to $11,719, and on a natural-gas gasoline were $2771. Reports made to the United States Bureau of Mines by all manufacturers of permissible explosives covering the year 1921 show that 93.5 per cent of such explosives sold during that year belong to the ammonium nitrate class. The total quantity of commercial ammonium nitrate used in permissible explosives during 1921 aggregated 25,381,500 lbs. The total quantity of nitroglycerin and “modified” nitroglycerin used in permissible explosives aggregated 3,974,000 lbs., for the manufacture of which approximately 1,766,000 lbs. of glycerol were used. By “modified” nitroglycerin is meant the products obtained by the nitration of a mixture of glycerol and certain compounds.
