INDUSTRIAL A N D ENGINEERING CHEMISTRY
JanttalsJI, 1925
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Vitamin Potency of Cod-Liver Oils’ XI-Butter Fats Produced on Summer Feeds By Arthur D. Holmes THEE. I,. PATCH Co., BOSTON, MASS.
T T H E present time
To obtain information concerning the vitamin potency produced. A number of some pediatricians of dairy butter, a supply of milk was obtained from several pure bred cows believed to prescribe cod-liver oil cows. These cows represented a number of well-known be representatives of differfor all infants, regardless of dairy breeds, but they were of different ages, and their ent breeds of dairy cows whether they are breast-fed pasture diet had been supplemented by different comwere selected as a source of or bottle-fed babies, in order mercial grain rations. milk. As far as possible, to insure the infant of a For the purpose of this study, the milk fat was separated information was obtained supply of the fat-soluble in the form of butter fat. The vitamin potency of the c o n c e r n i n g the breeding, vitamins adequate to meet different butter fats was determined under uniform feeding, age, and the period its body requirements for laboratory conditions. The results of these tests indiof lactation of each cow. growth and health. The cate that summer butter produced under favorable conThis information ‘is sumextent to which cod-liver oil ditions may have a vitamin potency equal to one-hunmarized below. is required in this connection dredth that of first quality cod-liver oils. depends largely upon two factors-namely, the inSOURCE OF MILKSIIOR DETERMINATION OF VITAMINA POTENCY fant’s body reserve. of the fat-soluble vitamins, and the fat- Holstein Name “Aseula Walker Pontiac”-American Registry No. 437,385 October 31 1917 soluble vitamin content of its diet. It is quite generally agreed Born Advance Has a 7-da; record of 389 pounds milk; 13.798 pounds fat; that an infant’s body reserve of the fat-soluble vitamins is registry 17.247 pounds butter a t age of 3 years, 7 months, and 21 days derived from the mother’s body reserve of vitamins and from Present Pasture supplemented by green oats, “unicorn” (cottonseed, ’corn, linseed meal, corn gluten, brewer’s grain, ration the vitamins contained in her diet. Considered on the basis wheat bran. hominy meal, and salt) of the future welfare of the child, it is to be hoped that the Freshened N o data available Sample Sample of milk for vitamin test collected July 17, 1923 mother had a large fat-soluble vitamin body reserve a t the A yrshird “Favorites Hope”-American Registry No. 55,927 time of conception, and that she consumed a vitamin-rich Name Born September 10 1918 diet during pregnancy. Advance Two years Ib6 days started on advance registry, finished registry record oi8766 pounds of milk containing 326.35 pounds of It is readily appreciated that, even though an infant may fat finished this record in 365 days Pastire supplemented by corn silage, grain, o.ats, and 12 be especially fortunate as regards its vitamin body reserve Present ration pounds per day ‘‘unicorn” (cottonseed, corn. linseed meal, corn gluten. brewer’s grain, wheat bran, hominy meal, a t birth, this cannot compensate for a vitamin-deficient diet and salt) for more than a relatively short portion of its growth period. Freshened June 13 1923. Probably third calf Sample Sample bf milk for vitamtn test collected July 17, 1923 I n view of this situation, it is evident that the infant’s diet Jersey “Polly of River Road’’-American Registry No. 486,795 must be chiefly relied upon as the source of the vitamins re- Name Born December 2%I919 quired for its well-being. Since during infancy and early Advance Merit test of’6087 pounds of milk, 394.89 pounds of fat in registry 365 days a t 2 years, 3 months of age childhood, milk forms the large portion or the whole of the Present Pasture supplemented by 20 pounds of apple pumice and ration 12 poinds dry grain daily (1Va pounds gluten 1”: pounds child’s diet, the vitamin content of milk is a question of excorn meal 31/: pounds bran, 51/r pounds grdund oats) treme importance to those responsible for the child’s de- Freshened April 26 1943. Second calf Sample Sample Af milk for vitamin test collected July 24, 1923 velopment. Jersey Name “Hilda Margaret of Green Meadow”-American Registry Occasionally, the pediatrician has as a patient an infant No. 421,020 whose tolerance for fat is materially below normal. I n such Born March 7 1917 Merit rerord of 9628 pounds of milk and 579.79 pounds of instances the pediatrician desires to reduce the volume of Advance registry butter fat in 365 days a t 4 years 8 months of age Pasture, supplemented by 24 p o k d s apple pumice and 9 fat in the infant’s diet and a t the same time maintain or per- Present ration pounds dry grain (ll/r pounds gluten, l l / r pounds corn haps even increase the fat-soluble vitamin content of the meal 21/a pounds bran 4 pounds ground oats) Januari 7 1923. Thirdcalf. Bred April 6, 1923 infant’s diet. To accomplish this he naturally turns to cod- Freshened Sample Sample miik for vitamin test collected July 24, 1923 liver oil, since this is the richest known source of the fat- Dutch Belted Name “Nina D.”-American Registry No. 1616 soluble vitamins. In order, however, accurately to substi- Born June 4 , 1 9 0 9 Advance tute cod-liver oil vitamins for the fat-soluble vitamins which registry No official test recorded Pasture, supplemented by grazing for a short time each day he takes from the child’s diet by withdrawing the cream, it Present on meadow of mixed grass and small amount of grain of ration is necessary that he have as definite information as possible unknown eom osition About June 1 18323. N o record kept concerning the vitamin content of both cod-liver oil and cream. Freshened Sample Sample of milk for vitamin test collected August 31, 1923 Dutch Belled In view of these needs for information concerning the vitamin Name “Carrie I,.”---American Registry No. 1684 content of milk fat, it has seemed desirable to determine the Born June 2, 1909 Advance vitamin potency of butter oils produced under normal conNo official test recorded registry Pasture supplemented by grazing for a short time each day ditions and it was for this purpose that this investigation Present ration on miadow of mixed grass and small amount of grain of was undertaken. unknown composition Freshened About June 1 1923. No record kept I n making this test of the vitamin potency of butter fats, Sample Sample of miik for vitamin test collected August 31, 1923 Devon it was desired to eliminate as many variables as possible, Name “Fair Florence’’-American Registry No. 1.5,217 and a t the same time not to deviate materially from the Born November 8, 1913 Advance conditions under which average market butter would be No official test recorded registry
A
Presented before the Division of Biological Chemistry a t the 67th Meeting of the American Chemical Society, Washington, D. C., April 21 to 26,1924. 1
Present ration
Freshened Sample
Pasture supplemented by green fodder corn and 3 quarts of a hixed ground grain which probably contained bran, linseed meal, and ground oats About August 10 1923 Sample of milk f6r vitamin test collected August 31. 1923
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INDUSTRIAL A N D ENGINEERING CHEMISTRY
It may be interesting to note that the ages of the cows varied from about 3l/2 to 14 years, and the period of lactation varied from about 3 weeks to 6 months. It may also be further noted that the mothers of the two Jersey cows (Polly and Hilda) were half sisters.
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The butter fats were prepared under laboratory conditions by allowing the cream to rise for 48 hours. The cream was then removed and churned in a small glass churn. The butter which was obtained was melted on a water bath, and the fat which separated was decanted and filtered through ordinary
January, 1925
INDUSTRIAL A N D ENGINEERING CHEMISTRY
laboratory filter paper. The butter fats which were obtained were free from the casein and water usually present in dairy butter, and for this reason were of comparable composition. In order to give some idea of the nature of the butter fats, the physical and chemical characteristics were determined by the usual laboratory methods. The results of these analyses are reported in the table. PHYSICAL AND CHEMICAL CHARACTERISTICS OF BUTTER FATS Specific Refractive SaponifiAcid BREEDAND NAME gravity index cation Iodine value OP c o w a t 40‘ C. at 40’ C. value number Per cent Holstein: Aseula Walker 0,9039 1.4555 215.7 44.35 0.2703 Ayrshive: Favorites Hope 0.9078 1,4550 225.7 43.50 0,1823 Jersey: Polly 0.9086 1.4542 228.3 39.34 0.1897 Hilda 0.9086 1.4549 225.8 38.16 0.8163 Dutch Belled: Nina D. 0.9035 1.4562 215.0 46.15 1.2360 Carrie L. 0.9066 1.4552 210.8 42.82 1.1340 Devon: Fair Florence 0,9082 1,4540 230.7 36.60 2,7570
For determining the vitamin potency of the butter fats under consideration, experimental animals about 4 weeks old were obtained from the ‘laboratory colony. These were placed on the usual experimental diet consisting of casein 18 per cent, peanut oil 22 per cent, cornstarch 28 per cent, milk sugar 28 per cent, and salt mixture 4 per cent. This diet was supplemented by a 0.2-gram tablet of dried brewer’s yeast daily. When the animals maintained on this diet had exhausted their body reserve of vitamin A, their diet was supplemented with varying amounts of the different butter fats. Detailed data of these tests appear in the accompanying charts, which supply information concerning the amount of butter fat administered, the amount of food ingested during 5-day periods, and the change in body weight of the experimental animals. The experimental period was limited to 45 days, and all tests were terminated at the end of this period regardless of whether the animals were gaining or failing. Of the five animals used in testing the vitamin potency of the HoIstein butter fat (Chart 44), the two receiving 30.9 mg. of fat daily did not recover from their malnutrition. Two animals receiving, respectively, 61.8 and 92.7 mg. grew slowly but consistently during the 45-day experimental period, and the rat receiving 123.6 mg. recovered rapidly from malnutrition. Five animals mere used in testing the vitamin potency of the Ayrshire butter fat. One animal receiving 29.5 mg. of this fat daily was unable to complete the 45-day experimental period. Of the four remaining animals which received from 29.5 to 118 mg. of butter fat daily, nonemade an entirely satisfactory growth throughout the whole experimental period. Considering the series as a whole, however, one would conclude that an amount of this butter fat not greatly in excess of 118 mg. daily would satisfactorily meet the vitamin A requirements of albino rats. The results obtained with the Jersey butter fats show a material difference in vitamin potency of these two butter fats. From the limited data available, it appears that something like 115 mg. of butter fat produced by Jersey cow “Polly” are required to supply sufficient vitamin A to meet the needs of albino rats, whereas only one-half or two-thirds as much of the butter fat produced by the Jersey cow “Hilda” is required to supply the same amount of vitamin A. The results of these tests are of especial interest, since the cows as noted above are slightly related (their mothers were half sisters) and had been for a considerable time maintained in the same barn under the same feeding conditions. In this
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connection, it may be noted that the cow “Hilda” which produced the butter fat of the highest vitamin potency was nearly twice the age of the other. Referring to the results obtained with the Dutch Belted butter fats, it is interesting to note that none of the rats used to test the butter fat produced by cow “Nina D.” were able to make satisfactory growth during the 45-day period; whereas with the second cow, “Carrie L.,” as little as 62 mg. of butter fat daily supplied sufficient vitamin A to enable the experimental animals to make satisfactory growth. It is interesting to note that both of these cows were 14 years old, which is considerably in excess of the age of the average dairy cow. Five experimental animals were used to test the vitamin potency of the Devon butter fat. Rat 532, which received 25.85 mg. of this butter fat daily, did not complete the 45day experimental period. Two rats were fed 51.7 mg. of butter fat daily; the results with these animals were practically identical as regards increase in body weight. The animals that received 77.55 and 103.4 mg. of butter fat grew a t about the same rate, but their increase in body weight was greater than that of the animals receiving 51.7 mg. of the butter fat daily. Conclusions
The data obtained from the tests reported here are not sufficient to permit of more than general conclusions concerning the vitamin potency of butter. Considering the tests as a
group, the results obtained show that as little as 51.7 mg. per day of butter fat produced on summer feeds can meet young albino rats’ needs for vitamin A. Since dairy butter should contain 80 per cent of milk fat, this amount of butter fat would be equivalent to five-fourths as much summer butter. It is very probable, however, that average summer butter has a lower vitamin potency, for, as noted above, the
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cows that produced the butter fats under consideration originated from carefully developed stock, and without doubt had received better care and rations than are given to the average dairy cow. No attempt should be made to compare the vitamin potency of the butter fats produced by the different breeds, since the age, feeding, period of lactation, and number of lactations were not identical for the cows of the differs n t breeds. In fact, considerable study of these factors will
be required in order to obtain definite information concerning the vitamin potency of average dairy butter. Acknowledgment
The author wishes to express his appreciation to Mason Garfield, The Dodge Brothers, John Gifford,and the American Woolen Company for supplying the milks from which the butter fats under consideration were obtained.
Determination of Aluminium in Nonferrous Alloys' .
By G. E. F. Lundell and H. B. Knowles BUREAUOF
STANDARDS, WASHINGTON,
D.c.
HE only difficulty in determining aluminium in nonferrous alloys lies in the number of operations that are
is rapid, it enables the analyst to see the aluminium, and it is quite accurate for a method of this type. It is not intend3d necessary. The usual preliminary separations leave that the method shall replace the longer and more accurate iron still associated with aluminium, and it is then necessary phenylhydrazine method, although in ordinary hands there either to separate it by precipitation with sodium hydroxide is not much choice between the two. Briefly stated, copper, zinc, lead, iron, nickel, manganese, or else to separate the aluminium by precipitation with phenylhydrazine after reduction of the iron. The practice of and similar elements are separated by filtration after precipiweighing iron and aluminium totation with sodium sulfide, and tin, gether and calculating aluminium antimony, arsenic, and any other A method for the determination of aluelements of the arsenic group are by difference after determining the minium in nonferrous alloys is described in iron is not entirely satisfactory next eliminated by acidification of which the usual alloying elements except when careful work is done and is the filtrate and a second filtration. phosphorus are separated from aluminium a dubious procedure at best when These operations leave aluminium by first precipitating with sodium sulfide but a 0.1 or 0.01 per cent of aluminas the only possible remaining conreagent and filtering, and then acidifying ium is in question. This is evident stituent in ordinary nonferrous the filtrate and again filtering. The prowhen one considers that nitric acid materials, and its absence is assured cedure is recommended for routine analysis digestions do not always remove all if no precipitate is subsequently and is not intended to replace the longer and obtained with the that Or treatment more accurate phenylhydrazine method. other hand, a isOn almost with sulfuric acid may not remove all lead, that these are precipitated sure evidence of aluminium if the by ammonia unless previously removed by hydrogen sulfide, reagents are free from this eIement, and the only ordinary that manganese and particularly zinc contaminate the am- contaminant is silica. Phosphorus, if present in the alloy, monia precipitate unless special precautions are taken, and will come down with the precipitate, as would &o a few that determinations of iron are seldom accurate to 0.01 per elements like vanadium and glucinum which are not expected in this material. cent and are often in much greater error. The direct precipitation of aluminium by the addition of Preparation of Solutions an excess of ammonia to a solution of the alloy is not desirable, because aluminium hydroxide is appreciably soluble in SODIUM HYDROXIDE SOLUTION (2.5 PER CENT)-Dissdve 25 $he excess of ammonium hydroxide which must be used to grams of sodium hydroxide (free from aluminium) in water and keep copper and zinc in solution. Moreover, the precipi- d i $ ~ ~ ~ ~ ~SoLuTIoN--Dissolve o ~ ~ ~ ~ ; D E150 grams of sodium tation but a p r e h i n a r y One, as the Precipitate will contain hydroxide (free from aluminium) in 1000 cc. of water, saturate all the tin and iron, nearly all the lead, and more or less 500 cc. of this solution with hydrogen sulfide, and mix with the remaining 500 cc. of solution. copper, zinc, manganese, and nickel. The use of solutions of sodium hydroxide or sodium sulfide Of hydrochlois not in good repute among analysts, and it is with hesitation A ~ I H~~~~~~~ ~ ~ ~sULPIDE ~ E WATER-Dilute ~ 10 cc. of bythat the authors propose a method in which a solution contain- drochloric acid (specific gravity 1.19) with 1000 cc. of water and ing these reagents is employed. Part of the prejudice against saturate the solution with hydrogen sulfide. CHLORIDESOLUTION (2 PER CENT)-Mix 30 CC. is caused by the be- of AMMONIUM the use Of the alkaline hydrochloric acid (specific gravity 1.19) with 200 cc. of water, havior of filters during filtration and washing, and Part by the add methyl red, neutralize with ammonia until the solution impure character of the reagents furnished in the past. These changes to a distinct yellow, and then dilute to loo0 CC. with objections do not carry much weight in the proposed method, water. because sodium hydroxide that is free from aluminium can Procedure now be obtained, and the filtration is simplified because only a part of a clear supernatant solution is filtered through a Dissolve 2 grams of the sample in 20 cc. of hydrocMoric acid (specific gravity 1.19) and 5 cc. of nitric acid (specific large filter and no washing is required. Having recounted the unattractive features of the method gravity 1.42). Boil the solution to expel chlorine and dilute it can now be said that it possesses enough desirable qualities with 50 cc. of water. Nearly neutralize the cold solution with to warrant its consideration for use in routine analysis. It sodium hydroxide solution (2.5 per cent, or stronger if much free acid is present), and pour it slOwly and with con;rtant Published by permission of the Director, 1 Received August 4, 1924. shaking into a 500-cc. volumetric flask containing 100 cc. of U. S. Bureau of Standards.
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