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Vitamins in Canned Foods X-The Vitamin Content of Some Common Vegetables’ E. F. Kohman, W. H. Eddy, and Celia Zall Gurin NATIONAL CANNERS ASSOCIATION. WASHINGTON, D. C., AND TEACHERS COLLEGE, COLUMBIA UNIVERSITY, NEWYORE,N . Y.
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URNIP g r e e n s h a v e long been a southern dish. W i t h i n recent years commercial canning of turnip greens has developed to considerable magnitude. It was of interest, therefore, to make a study of the vitamin content of canned turnip greens. Its s i m i l a r i t y to spinach in being extremely rich in v i t a m i n s A and C raised the interesting speculation as to how these green v e g e t a b l e s compared with various other vegetables commonly eaten raw.
Canned turnip greens, head lettuce (inner and outer leaves), celery (bleached and green), and raw carrots (whole and shredded for 1 to 3 hours before feeding) have been studied for their relative vitamin content. Canned turnip greens, like other green leafy vegetables, are outstandingly rich in vitamin A, being unsurpassed by any other vegetable and comparable to spinach. Twenty-five milligrams supply more vitamin A than 5 grams of bleached celery and as much as 500 mg. of unbleached celery. Canned turnip greens, head lettuce, and celery are not rich sources of vitamin B. There is more of the B1 (G) fraction than of the B1 fraction in canned turnip greens. Head lettuce seems to be superior to celery and canned turnip greens in its content of the vitamin B complex. In view of the general belief that raw vegetables are always a potent source of vitamin C, head lettuce, celery, and raw carrots were found to be surprisingly low in this factor compared with canned turnip greens. Two to four grams of turnip greens gave better growth and less evidence of scurvy than 5 grams of celery; green or bleached, 10 to 15 grams of head lettuce, inner or outer leaves, or 10 grams of whole or 15 grams of shredded carrots.
Bezssonov (2) demonstrated that a similar process with raw potatoes r e s u l t e d in a very marked loss of vitamin C content. For example, he found that four guinea pigs fed for 83 days, with an adjunct of 15 grams of raw potatoes as the sole source of vitamin C, were kept free from any s y m p t o m s of s c u r v y . Bezssonov was interested in learning whether the vitamin C resided in the juice or in the pulp of the potato. Upon g r i n d i n g a n d pressing the juice from p o t a t o e s with a hydraulic press and feedVitamin C ing it within 21/2 hours, he I n searching for data as to found that two guinea pigs the v i t a m i n C c o n t e n t of receiving 30 cc. per day surhead l e t t u c e as grown in vived o n l y 28 days. Two of the guinea pigs receiving this country, no record was found of this most widely 40 cc. per day survived the 30-day experimental period, used salad v e g e t a b l e having been subjeited to a test but one declined verv raDidlv of its vitamin C content. Holst and Frolich (6), in their during this period. Three guinea pigs receiving, respectively, early work on scurvy, give data in which 15 grams of endive 5, 7, and 10 grams of the pulp died of scurvy within 29, 26, were fed for 2 months followed by head lettuce, with apparently and 32 days. Four animals receiving 5 grams of pulp and no symptoms of scurvy. Scheunert (8) states that as little 10 CC. of the juice died of scurvy in 51, 52, 56, and 75 days. as 1 to 2 grams of head lettuce protects guinea pigs from The writers have been interested in the significance of this scurvy. experiment because it may have a bearing in many directions. Likewise no record was found of celery having been tested It was thought that the grating or shredding of carrots might in this country for its vitamin C content, although the above entail similar consequences. Therefore, a study was made of authors give some data with reference to it. Scheunert covers carrots for this purpose. The general use of celery in the the matter by the simple word “Gut.” We therefore raw form and the lack of data as to its vitamin C content deemed it essential that data of this kind be available, par- led to the inclusion of this vegetable as well. The results of such studies of carrots (whole and shredded), ticularly as in this country such products are widely distributed and the time between harvesting and consumption head lettuce (inner and outer leaves), celery (green and may be considerable. Although there are no data available bleached), and of canned turnip greens are given graphically as to the effect of this storage period, tests on other products in Chart I. In the feeding experiments recorded, yqung such as cabbage (3) and apples (6) have shown that in general guinea pigs, weighing between 300 to 350 grams, were given the vitamin C content diminishes during storage. McCollum the vitamin C adjuncts noted with all that they cared to and Simmonds in their well-known book, “The Newer Knowl- eat of the following basal diet, the ingredients of which were edge of Nutrition,” recommended two salads a day as a intimately mixed: wholesome dietary r6gime. One thought behind such recParrs ommendation is evidently the securing of an adequate supply Baked skimmed milk., . . . . . . . . . . . . . . . . . 30 Equal parts of rolled oats and bran.. . . . . . 59 of vitamin C in the diet. As the usual basis of a salad in this Butter f a t . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Cod-liver oil.. . . . . . . . . . . . . . . . . . . . 1 country is head lettuce, this implies that the authors believe Sodium chloride.. . . . . . . . . . . . . . . . . . . 1 head lettuce to be rich in vitamin C. Raw carrots have likewise been recommended as a valuable Autopsies were performed on all the animals a t death. If the source of vitamin C. When used for this purpose, they are animals survived the SO-day feeding period, they were gassed usually served in a salad in either a grated or shredded form. and the autopsies then performed. The severity of the scurvy There is reason to suspect that this grating or shredding may symptoms is given at the end of each graph by a figure rephave a material effect on the vitamin C content, unless the resenting the scurvy score. The maximum scurvy score carrots are consumed promptly after this preparatory process. in the system used is 24. Several conclusions are indicated in this chart. The shred1 Received March 26, 1931. Presented before the Division of Agriding of carrots held for only 1 hour previous to feeding results cultural and Food Chemistry at the 81st Meeting of the American Chemical in a somewhat lower vitamin C content. With carrots held Society, Indianapolis, Ind., March 30 to April 3, 1931. ~~
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Chart I-Growth
Curves of Guinea Pigs Receiving Various Vegetable Adjuncts a8 the Sole Source of Vitamin C. The Initial Weight of the Animals Varied from 300 to 350 Grams T h e number a t the end of each curve indicates the severity of the scurvy symptoms in a system in which 24 is the maximum.
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in vitamin C, although celery proved to be considerably better as a source of vitamin C than head lettuce-10 grams daily being adequate for protection against scurvy in guinea pigs. In the case of the two varieties of celeb, some difference in favor of the green variety seemed to be in evidence. I n striking contrast to the vitamin C content of the above foods used in the raw state is the high vitamin C potency of canned turnip greens. I n this respect turnip greens resemble spinach, which has previously been reported (4). Guinea pigs receiving from 2 to 4 grams of turnip greens in canned form made as good growth over a 90-day feeding period as similar animals receiving 15 grams of carrots, 25 grams of head lettuce, or 10 grams of celery. It is possible that a smaller dosage of head lettuce might have been adequate but 15 grams were not adequate. Although good growth resulted on 2 grams of turnip greens, there was e v i d e n c e of scurvy. Even on 4 grams of turnip greens, one animal showed slight symptoms of scurvy on autopsy, although its condition otherwise was excellent. Vitamin A Curves of Rats Receiving Various Vegetable Adjuncts as the Sole Source of Vitamin A By considering the base line or abscissa for each product as 30 grams, the initial Chart 11-Growth
weight of each animal may be noted.
Data with reference to vitamin A are summarized in Chart 11. For these experiments, rats 28 days of aee were Dlaced on the Sherman and Munsell basal diet, 379rA, untif they showed a definite loss in weight and, in most cases, evidence of xerophthalmia. This period was from 30 to 35 days, and a t the end of this time the rats varied considerably in weight. By considering the base line or abscissa for each product on Chart I1 as 30 grams, the actual weight of each animal a t the beginning of the feeding period with the vitamin A adjunct may be observed. When the growth curve does not extend over the entire 60 days, it signifies that the animal died before that period. I n vitamin A content turnip greens likewise are excellent. Fifteen milligrams per rat per day resulted in vitamin A
3 hours the effect is somewhat greater. Based upon the growth curves, the gross appearance of the animals and autopsies after the 90-day feeding test indicates that the minimum protective dose for whole carrots, shredded carrots held 1hour, and shredded carrots held 3 hours, is, respectively, 15, 18, and 20 grams. The second conclusion indicated by Chart I is that head lettuce is surprisingly low in vitamin C content, considering its wide use because of this factor and the relatively high potency of cabbage. Fifteen grams per day per guinea pig were not adequate in protecting against scurvy, whereas 25 grams provedto be a d e q u a t e . Intermediate a m o u n t s were not fed. There was no appreciable difference between the inner leaves and the outer leaves. It should be noted that the outer green leaves and the inner bleached leaves represented the same head of lettuce. I n contrast to the comparison of green and bleached leaves of the same head of lettuce, in the case of celery, bleached bunches of celery were studied in comparison with green bunches of c e l e r y that had never been s u b j e c t e d to any bleaching process. Both the green and the bleached celery Chart 111-Growth Curves of Rata Receiving Various Vegetable Adjuncts a8 Vitamin B Supply were found to be low By considering the base line or abscissa for each product as 30 grams, the initial weight of each animal m y be noted.
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deficiency, but 25 mg. were adequate to avoid any evidence of vitamin A deficiency and to permit good growth. A1though 50-mg. amounts were also fed, the condition of the animal was not improved over that of 25 mg. Vitamin B
Data for vitamin B are summarized in Chart 111. For determining vitamin B, 28-day-old rats were used. The Sherman and Spohn basal diet, 107, was kept before them at all times, and the various vegetable adjuncts to supply vitamin B were fed separately. By again regarding the abscissa, or base line, for each product on Chart 111, as 30 grams, the weight of each animal a t the beginning of the feeding experiment may be observed. Since celery was low in vitamin B complex, experiments are also given in which the celery was supplemented with varying amounts of yeast. In the case of the canned turnip greens, a supplement of Jansen and Donath No. 31 preparation (9) was also given to supply the antineuritic factor. I n vitamin B content turnip greens resemble spinach in their low content of the antineuritic or B1 fraction. Amounts up to 5 grams per rat per day were inadequate as a source of B complex. When B1 was supplied in the form of 60 mg. of the Jansen and Donath preparation daily, 3 grams were adequate to avoid any Bz (G) deficiency, but 5 grams resulted in better growth. Roscoe (7) recently reported data on the vitamin B complex of lettuce. As a source of the B1fraction, she reported that lettuce produced a gain of 53 grams in 5 weeks when fed
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daily in 0.3-gram amounts (dry basis or 3.75 grams wet basis). As a source of the Bz (G) fraction, 0.6 grams (dry basis) were required to give a gain of 55 grams in 5 weeks. She does not state whether she made an actual moisture determination or used an average figure, presumably the latter since she gives the same proportion of dry matter in cabbage. According to Atwater and Bryant (1) 0.3 gram of dry material would be equivalent to 5.2 grams of fresh lettuce. The present writers purchased head lettuce daily and made no moisture determination. I n view of this, their Bgram amounts of lettuce should correspond to about 0.3 gram of dry matter. The average growth increment from 5 grams of lettuce as a source of the vitamin B complex was 33 grams in 60 days for the inner leaves and 45 grams for the outer leaves. Celery proved to be a much lower source of vitamin B complex, 5 grams of celery hearts being inadequate to maintain life for 60 days, while the unbleached was somewhat better. Canned turnip greens contain the B1 fraction in relatively low concentration, but are more potent in the Bz (G) fraction. Literature Cited Atwater and Bryant, U.S. Dept. Agr., Bull. 18 (1906). Bezssonov, Compl. rend., 171, 92 (1921). Eddy and Kohman, IND. ENG.CmM., 16, 52 (1924). Eddy, Kohman, and Carlsson, Zbid., 17, 69 (1925). Holst and Frolich, 2. H y g . Infckfionskrankh., 71, 1 (1912). Kohman and Eddy, IND. ENG,CHBM., 18, 1261 (1924). Roscoe, Biochem. J . , 44, 1754 (1930). Scheunert, “Der Vitamingehalt der deutschen Nahrungsmittel.” Springer, 1930. (9) Williams, Waterman, and Gurin, J. Biol. Chcm., 87, 3 (1930).
(1) (2) (3) (4) (5) (6) (7) (8)
A Microscopical and X-Ray Study of Pennsylvania Anthracite’ Homer Griffield Turner2and Harold Victor Andersona LBH~GH UNIVERSITY, BBTHL.EEEY, PA.
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LL coals are composed
Pennsylvania anthracite is composed of three constructure closely analogous largely of three constituents-anthraxylon, attritus, and fusain. to, if not identical with, gras t i t u e n t s , to which A knowledge of the constitution of coal as revealed phitic carbon. A m e r i c a n students of coal under the microscope is necessary to a correct interAnthraxylon constitution have given the pretation of x-ray analyses. This is shown by the n a m e s “anthraxylon,” “atfact that the diffraction patterns of the constituents Anthraxylon embraces all tritus,” and “fusain.” The of anthracite show marked differences. those ingredients of coal which The anthraxylon particle is similar to graphitic have been derived from the proportions of these constitucarbon and gives a difkaction pattern resembling woodyportionsof plants, such ents in different coals are s u b j e c t to wide variations. cellulose, thus showing a de5nite arrangement of m tree t r u n k s , b r a n c h e s , colloidal micelles. twigs, r o o t s , e t c . These I n one coal the anthraxylon may p r e d o m i n a t e ; in anThe attritus contains almost all the mineral matter woody constituents have been other coal the attritus may of anthracite, as shown by radiographs and sharp split and f r a c t u r e d by the predominate; the fusain is a Debye-Scherrer rings in the attritus diffractionpattern. processes of d e c a y a n d minor constituent with relaw e a t h e r i n g in the original tively no great variations in its proportions. swamp, and this causes them to appear as strips and lenses These three constituents of Pennsylvania anthracite have varying in thickness from mere films to bands that can be been identified through the microscope and radiographs, readily isolated by hand. These woody constituents are isolated, and analyzed by means of x-ray diffraction methods. visible to the naked eye in the form of the brightest lamiThe anthraxylon yields a true fiber pattern characteristic nae of the specimen. Under the microscope they show cell of a very finely divided material; the attritus pattern shows structure varying from almost perfect cells to those that an absence of the fiber structure and the presence of Debye- have been compressed to the vanishing point or effaced by Scherrer rings. The anthraxylon, furthermore, shows a maceration. 1 Received April 13, 1931. Presented before the Division of Gas and Fuel Chemistry at the 81st Meeting of the American Chemical Society, Indianapolis, Ind., March 30 to April 3, 1931. * Director of research for the Anthracite Institute: assistant professor of geology, Lehigh University. * Associate professor of chemistry, Lehigh University.
Attritus
The attritus of coal is made up of many kinds of plant tissues and fragments, although one or more plant constituents may at times predominate. In it we find the more
