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160 kilowatt hours; the gas produced from coking 3j,ooo,ooo tons coal (1914)would yield over 800,000 continuous horse power, which would be sufficient for the fixation of an amount of nitrogen equivalent to an additional 1,400,000 tons ammonium sulfate. The gas, being a by-product, is produced a t slight cost and the installation for the development of the power is limited to comparatively inexpensive gas engines. As a concrete proposition, in case the normal production of by-product ammonia was not sufficient for the emergency a t hand, it would be possible for the Government to install byproduct ovens and use the gas for the generation of electrical energy for the fixation of nitrogen. This could be put into operation quickly and a t a comparatively small cost. Ammonia would be produced as a by-product a t the same time, and use could be made of the coke and other products. Were the emergency postponed to a time when all the coke was produced in by-product ovens and a market had been found for the gas, use could be made of the enormous quantities of waste and low-grade coals, the lignites and even the peats available, all of which ou distillation yield ammonia and combustible gas suitable for use in gas engines. Or should it be desired t o effect a permanent and large production of ammonium sulfate, the use of coke could be encouraged by restricting the use of bituminous coal where coke can be used as advantageously. The Government itself could produce coke and sell it a t the same price as coal, reserving t o itself the ammonia and other by-products. S o t only would by-products worth $1.50 per ton of coal be conserved, but an increase of about 20 per cent in the efficiency of the coal as a producer of power would be effected. Likewise, the smoke nuisance would be abated. It is reported that such a restriction has been in effect in Germany since 1914. This is a measure which would have to be inaugurated by the people, for the producer of coal is interested in the use of more coal, not in its more economical use; and the producer cf coke is more interested in the maintenance of good prices for by-products than a larger production. It is a suggestion which is deserving of very careful consideration, for, with the coal now wastefully used, is lost enormous quantities of ammonia and benzol (and power). This rigid conservation would afford agric*ulture the best of fertilizers and the puhlic 3 s a whole an excellent motor fuel, a t a fraction of their present cost. The basis of practically all explosives is nitric acid. This, usually, is prepared from sodium nitrate. It may bc prepared
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also from ammonia. When ammonia gas and air, mixed in the proper proportions, are allowed t o flow through platinum gauze or other suitable materials, known as catalytic agents, heated to the proper temperature, the ammonia is converted into nitric acid. While the chemical reaction involved has long been understood, its recent modifications and commercial application have come t o be known as the Ostwald process for manufacturing nitric acid. It is reported that this process is in successful operation both in England and Germany; t h a t in the latter country all the nitric acid being produced is obtained by means of it. If, in our country, it could be developed to a degree of efficiency where nitric acid obtained by means of it from by-product ammonia could be made t o compete so successfully with Chilean nitrate as to exclude it from American industries, the large sum now annually expended for that commodity in a foreign market could be retained for the domestic market. Obviously the Ostwald process is of prime importance. Steps should be taken a t once to determine all the conditions surrounding its best performance. I t is claimed t h a t already it has been developed to the stage where j3 per cent nitric acid can be produced by means of it a t a cost of $0.03 per lb., inclusive of cost of the ammonia. It should be investigated thoroughly in order to establish the best technique of the operation, to further reduce the operating cost, t o further increase the yields, t o develop new and cheaper catalytic agents and to make such modifications as would render the people free of patent restrictions. By way of summary it should be added that for times of peace America has a supply of nitrogen compounds adequate for both fertilizer and munitions purposes. This supply includes imported nitrate which is adequate for the munitions indutry, and domestic by-product ammonia which contributes to the fertilizer industry. I n time of emergency, should importation be prohibited, the by-product ammonia could be withdrawn a t once from the fertilizer industry and applied to the munitions industry. This source, by normal processes, is being developed to a degree where no longer will any doubt remain as to its entire adequacy for all emergencies. Accompanying this development ~ ai111ua:Ijr to a conservation is Laking piace worth I I I ~ I Imilliuns the American people. ’
D ~ ~ P A R T V S N OF T AGRICULTURE
WASHINGTON
THE C H E M I S T IN RELATION TO FOOD CONTROL
I
Papers presented a t the 52nd Meeting of t h e .4MERICAN CHEMICAL SOCIETY, Urbana-Champaign, April 18 t o 21, 1916
THE CHEMIST IN FOOD CONTROL AS RELATING TO THE ENFORCEMENT OF LAW ny I,. M. TOLMAX Chief, U. S Food a n d Drug Inspection, Central District
The work of the chemist in food control, in so far as it relates t o the enforcement of regulatory laws, is largely the obtaining of scientific evidence which may be of value in detecting the adulteration or misbranding of food products. He must not, however, be limited to the use of chemistry in obtaining this evidence, but will find that chemistry is only one of the many tools t h a t he must use and his effectiveness and the value of his evidence will be very much restricted unless he brings t o bear upon the question the assistance of bacteriology, botany, physics, and other of the sciences and arts. The adulteratioii of food products, in a general way, consists in the debasing or imitation of recognized food products, and the Food and Drugs Act defines these various forms of adulteration as follows: “The mixing of any substance, which reduces or injuriously affects the quality or strength of the article; such a? the addition of water in milk.
“The substitution of foreign material, in whole or in part; such as the mixing of distilled vinegar with cider vinegar. “The removal of any valuable constituent of the article, in whole or in part; such a5 extracting the essential flavoring oil from cloves. “The coloring of an article, so as to conceal its inferiority; such as coloring noodles yellow so as to imitate the color of eggs and conceal the fact that there is a lack of this material. “The addition of a deleterious or poisonous substance; such as the addition of salicylic acid to preserves in such quantities as might render the article injurious t o health. “The using of spoiled or decomposed products, such as moldy tomatoes in catsup.” All of these forms of adulteration above enumerated assume the existence of a n unadulterated or genuine product, and the basis of most of t h e work in t h e obtaining of evidence of such adulteration depends largely on comparison of the genuine with the adulterated article. The greatest difficulty in the work is t o get ail accurate standard with which we can compare or measure the article under examination. I t is Comparatively easy t o detect and measure adulteration if me have the article before it is adulterated t o compare exactly with t h e article aftcr
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i t has been adulterated. For instance, if we have a pure cider vinegar, before its mixing with distilled vinegar, to compare with the mixture, we can tell with accuracy and measure almost exactly the amount and kind of the adulteration. If we have a sample of the cloves before the extraction has been made, to compare with the extracted product, we can measure accurately the amount of oil t h a t has been removed. If we have a sample of the milk before it is watered, to compare with the watered sample, the detection of the adulteration is simple and conclusive; and so on through the various forms of adulteration. The best and most accurate standard or measuring rod is the product itself before it has been adulterated. Such standards, however, are not always, or often, available for the food chemist. I n fact, his chief work might be said to be to obtain the best possible standard to use as a measuring rod, and he should bear in mind t h a t the farther he departs from the thing itself the more subject to criticism becomes his evidence. I n general, there are several kinds of standards or measuring rods which are employed, and I am giving them in the order of their value as it seems to me: ( I ) The product itself, before adulteration. ( 2 ) Records of analyses of similar products, as nearly as possible representative of the thing itself. (3) The general literature on the class of products and compilations of data. The chemist finds, when he starts to use any of the other standards than the product itself, that there is such a natural variation in products that his standard of comparison must become either a maximum, minimum, or average, so that, while he may be able to prove t h a t the product is adulterated, the accuracy of his estimation of the amount of the adulteration is very much diminished. If he is compelled to use only the data published in the books and literature as to the composition of the product under consideration, he will find that there is probably such a wide variation as to the composition of the product that his accuracy of measurement is very slight. He also finds this condition to exist-that records have been made of many samples regarding which there must be doubt as to their genEineness and of which there is little infornation as to their exact kind. STEPS I N ANALYSIS O F A FOOD
The skill of the food chemist, therefore, depends largely on his ability to classify the article under examination, and then to obtain a proper standard of comparison, and, finally, to make an accurate comparison. Assume, for instance, t h a t the problem presented to the chemist is a sample of ground black pepper which the inspector has collected and which, for reasons he has obtained from the trade and from a general knowledge of the situation, he believes has been mixed with some material whereby its price has been reduced. The chemist takes the sample and examines it for clues, and his first work. should be to classify the article as closely as possible. I n order to do this, he must first know who is the manufacturer, where the product is produced, and, if possible, from what it was produced. At least these should be the lines of thought toward which he should direct his attention. Then he should consider the product itself, as to its color and appearance in comparison with samples of known origin and of the various kinds, since this color or appearance may be sufficiently decisive to give an indication as to the variety of pepper used in its manufacture or as to the presence of probable adulterants. After he has very carefully considered the article itself from the standpoint of appearance, taste, smell, and character, he should then make his analysis, and, after this has been completed, we may be able to say that the product has the appearance of a black pepper, that the microscope does not show any foreign material, that the product has an abnormally high ash and crude
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fiber, and is somewhat peculiar in color and appearance; but we must still further classify the product we are working with before we can obtain a proper measuring rod with which to compare. We know that there are on the market a t the present time a t least four kinds of black pepper used commercially, and this product may be made from any one or from a mixture. If by any means we can show that it is made from one special variety, we have classified the product to a very considerable extent, so that we can eliminate from comparison the data, analyses and information regarding the other three varieties. For, if we go to the published results of analyses, we find that there is a wide variation in the compositions of these four varieties of pepper commercially on the market. We also find that, unless by some means we can exclude from consideration a t least one of these varieties, we will not be able to show that the product is adulterated, for we find that the data on Acheen peppers show an especially high crude fiber and ash, and, in all probability, we will find analyses of supposedly genuine products which will have a higher ash and higher crude fiber than the sample under consideration. On the other hand, if we can exclude this grade of pepper from consideration by some means, we find that the other peppers vary only within rather narrow limits, and we will have a fairly satisfactory standard or measuring rod with which to compare our sample under consideration, and from which comparison we will probably be able to prove the adulteration. If we now compare our analysis with the data on Singapore, Alleppey and Tellecherry peppers, we find the crude fiber and ash in our sample are excessive, probably due to the admixture of pepper shells on account of the fact that no foreign ingredients were found. I n order, however, to further limit our standard, and in order to be able to estimate approximately the amount of adulteration, which is a very desirable thing to do, we must develop if possible a still more accurate standard'of comparison. This we may be able to do if we can limit our standard to a single variety. In order, however, to get such a standard, i t is necessary for us now to go back to a consideration of the manufacturer, what we know of him or of the raw materials he is using, what peppers he has on hand, and mhcther or not he has purchased or has in his possession pepper shells. I n order to get such information, we have to depend on other methods than pure chemistry, and work with the inspectors, without whom our work would be exceedingly difficult. If then we can find t h a t a certain grade or kind of pepper is exclusively used and that this manufacturer has purchased pepper shells from time to time and samples of these can be obtained, we have a possibility of preparing a standard for measuring our product which will give us a very much greater accuracy, especially in a quantitative idea. If we had been compelled to depend upon the literature as a standard, or upon our knowledge of the composition of various kinds of peppers, or practical standards adopted by regulation or law, we would have been very much in the dark in regard to what our results meant, but, by classifying our product and eliminating from our standard everything except what is truly comparable, we are able not only to show that adulteration has taken place but approximately the quantity. After we have reached our conclusion and go back over the evidence, we find that we have used the eye, the taste, the microscope, knowledge of trade conditions, and study of factory methods combined together with a little chemistry. ADVANTAGES OE" INDIVIDUAL STANDARDS
The chemist in reality might be considered as a scientific detective who must follow every clue until he makes out his case and obtains a true and correct standard with which he can compare the unknown. The possibilities of this method of
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making an individual standard for each case are much greater, I think, than most food chemists have realized or have used. Take, for instance, the question of watering and skimming of milk. If our analytical data indicates the possibility of the addition of water and we turn t o the literature for information, we find a most confusing condition. Thousands and thousands of analyses of milk, widely varying, have been published, and it is doubtful if any of the mixing would be detected if these records were permitted t o be used as a standard, but it is recognized t h a t different breeds of cows give milk of entirely different composition, so that the first thing that should occur t o us is to determine from what breed of cattle the milk which we have analyzed comes. Then it is possible for us to eliminate from our comparison all of the data which has been published or recorded on c o m of other breeds, b u t i t is almost always a practicable and feasible proposition t o get a sample of the milk under consideration before it has been adulterated. By going out t o the farm, we can find out the kind of cattle which are being milked, we can stay there during the milking periods and obtain samples of the milk under our personal supervision in such a way that water could not be added. Tt’hen we have obtained a n average sample of the milk of the night and morning and have obtained the analysis, we then have a n accurate standard with which t o compare the product under consideration. If it is not possible t o get such a sample, we can a t least narrow our standard down to determining the breed of cattle. If it is necessary for the chemist to take a sample of milk and analyze i t without any information as t o its source and he is unable t o obtain any information as t o its source, we have a very unsatisfactory and inaccurate standard or method of proving adulteration. We must then take into consideration the wide variations recorded in the literature, and our final conclusion must be a more or less accurate guess. It would be possible t o go on and outline a number of other cases where it is possible and feasible practically to obtain the product itself before adulteration as a standard for comparison, b u t I think these two illustrate a general principle toward which the intelligent and thoughtful man must work in every case. \\’e know from our experience that the composition of natural products varies from time to time, from season t o season, and from location to location. The article now on the market may not have existed a year or ten years ago. Take, for instance, the grapes of a certain section, which are peculiar in that they have certain qualities, and a grape juice made from them has certain peculiar characteristics as to acid, sugar, and color. The grape juice made from the same variety of grapes, grown in another section, might be materially different, so that, in our classification and comparison of grape juices, we must try t o eliminate from consideration grape juices which were not made under the same conditions and in the same location. The first thing the analyst should do in examining grape juice is to determine, by taste and appearance if possible, the kind of grapes from which manufactured, and, if possible, the place of production. Then he is in a fairly good position t o eliminate from consideration the analyses and data which have been published on other varieties. It has seemed t o me, during the consideration of this paper, that some results published in the past have been of comparative little value, because exact detailed descriptions of the samples are not given. I t seems to me that data, in order t o have the greatest value as a standard for comparison, must describe exactly in minutest detail the kind, place of production, and every other factor which would have an effect upon the composition of the product. The idea was spread abroad some years ago that it was impossible t o determine by an analysis whether American beers were made from malt or malt substitutes, because the recorded
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analyses of foreign beers made from a certain kind of malt were similar in analyses t o American beers made from malt and malt substitutes. Of course it was impossible t o determine, by analyses of American beers and comparing them with data on German beers, that there was any substitution for malt, but why should we do so unscientific and inaccurate a thing as t o permit ourselves t o use for a standard for comparison a product which is not a true standard? The proper standard for comparison of American beers would be American beers produced from the malt used in this country and under the conditions prevailing in this country. The point that I wish to make, and to reiterate, is that it is not scientific or proper t o use, as a basis of comparison, data or records or analyses of products which are not the same as the product with which we desire t o make the comparison, We have in our literature many, many analyses of maple sugars and maple products, and we find that maple products coming from certain sections are quite different in composition from those produced in other parts of the country. It is impossible, in some cases, to reach any conclusion as to whether or not a maple product is adulterated if we must consider in our comparison the wide range of variations which have been found in these products made all over the country, but, if we can limit ourselves to maple products made in Ohio, or maple products made in Yermont, or maple products made in Canada, for the basis of our comparison, if we can classify our unknown sufficiently to eliminate certain kinds of products, we may be able to get a fairly accurate standard or measure. In other words, the first thing t o do with a n unknown is t o classify the product by smell, taste, appearance, analysis, method of manufacture, and knowledge of varieties on the market. Then, when we have classified our product as far as possible, we must limit our standards so that we do not include in them anything but the products properly comparable, and, finally, we must make our comparison as accurately as possible. It is perfectly obvious, it seems t o me, that our measuring rods or standards of comparison must be really measuring rods, and we must not deceive ourselves into thinking that they are real when as a matter of fact they are not. I recently read an article in which the man’s success had depended upon his being able to see things as they were, and t o do the obvious thing, but t o do the obvious thing requires two things-knowledge of the situation and thought regarding it, and it seems to me that these are the two things which every food chemist should apply to the question of a proper standard of comparison. CHICAGO
FOOD CONTROL FROM A STATE VIEWPOINT R y DAVIDKLEIX
Chemist, Illinois S t a t e Laboratory
The chemical aspect of state food control work is so intimately connected with the inspection and field investigation phases of the problem that it is not possible to limit the province of the chemist and t o confine the discussion within such bounds. To be sure, the chemist is supposed to analyze the samples sent in by the inspectors, and t o render an opinion upon their compliance with the provisions of the law. But the chemist’s greater contribution t o food control lies in a field not circumscribed by the walls of a laboratory : his sphere of activity should be co-extensive with the boundaries of the state. I refer to the application of scientific principles in the regulation of lood industries, for the method employed in investigating arid controlling a n industry should differ in no essential from the course pursued in carrying out an investigation of some highly theorctical subject in the university. Just as every research problem has its characteristics to which the general principles of scientific procedure must be adapted, so has each state its characteristics which must be taken into consideration. Among these may be
