194 THE VITAMINS 



ments, guinea pigs were fully protected against scurvy by 1 gram 

 daily of rutabagas and from 1 to 2 grams of the early turnips. 



Radishes, which belong to the same family as the turnip and cab- 

 bage, have received little attention as to vitamin content, but Shinoda, 

 Fujimaki and Saiki (1927) in a study of the vitamin content of Jap- 

 anese food products secured protection against scurvy in guinea pigs 

 with 5 cubic centimeters daily doses of radish juice and noted a higher 

 content of vitamin C in the peelings than in the peeled fruit. 



Carrots are reported to be less rich in vitamin C than turnips. Hess 

 and Unger (1919) called attention to distinct differences in the anti- 

 scorbutic properties of old, as compared with fresh young carrots par- 

 ticularly after cooking. It was found that while 35 grams of old carrots 

 were sufficient to protect a guinea pig from scurvy when fed raw, after 

 cooking for three-quarters of an hour their addition to the dietary 

 proved insufficient for protection. In a parallel test with fresh young 

 carrots 25 grams proved adequate for complete protection even after 

 cooking. It was pointed out that in such cases as this the fresh young 

 vegetable may have a double advantage over those which are older 

 and tougher, since in the first place the younger or fresher specimens 

 may be richer in antiscorbutic vitamin to start with and as the older, 

 tougher vegetables require more prolonged cooking they are apt to 

 undergo a greater loss of antiscorbutic during the cooking process. 



Hess also pointed out (1920, p. 160) that the loss of antiscorbutic 

 value in the boiling of carrots is due to destruction and not merely 

 to extraction of the antiscorbutic vitamin since the water in which the 

 carrots had been cooked was found by feeding experiments to have 

 little if any antiscorbutic value. This is in contrast to observations 

 showing considerable amounts of vitamin B in the "water" of cooked 

 or canned vegetables. The difference is probably due to the greater 

 susceptibility of the antiscorbutic vitamin to heat, which would result 

 in its destruction rather than its accumulation in the boiling water sur- 

 rounding the cooking vegetable, whereas the equally soluble and more 

 stable vitamin B would accumiulate in the cooking water to a much 

 larger extent. Less easily understood is the further finding by Hess 

 that the acidulation of the cooking water with vinegar did not reduce 

 the loss. Foods naturally acid seem always to retain their antiscorbutic 

 property relatively well under heat treatment, while attempts to con- 

 serve the antiscorbutic vitamin of other foods by addition of acid seem 

 to give variable results. 



Largely as the results of his experience with carrots, Hess (1920, 

 pp. 160, 161) laid much emphasis upon the view that vegetables must 



