VITAMIN C 193 



The antiscorbutic value of Hawaiian-grown pineapples has been 

 determined by Miller (1925), who found that 5 grams daily of the 

 fresh fruit was sufficient in curative tests. Canned pineapple was some- 

 what less effective, but a mixture of 7 grams of canned pineapple and 

 5 cubic centimeters of the canned juice, the whole corresponding to 

 7.7 grams of fresh pineapple, sufificed for renewal of growth and pre- 

 vention of scurvy. The apparent slight destruction of vitamin C in the 

 canned product could not be attributed to a decrease in hydrogen-ion 

 concentration for the pH values of both fresh and canned juice lay 

 between 3.5 and 4, an acidity higher than that of canned tomatoes. 

 Miller (1926) also gave a somewhat higher value than Delf to the 

 papaya as a source of vitamin C. Although the minimum dosage was 

 not determined, three grams daily appeared to give as complete pro- 

 tection and to cause as good gains in weight as 5 grams. 



The Chinese persimmon (Diospyros kaki) was reported by Embrey 

 (1923) and Hsu (1928) to be low in vitamin C, the minimum pro- 

 tective dose being from 25 to 30 grams of the fresh fruit. According 

 to Iwasaki (1927), in a Japanese report with English summary, the 

 same fruit, known in Japan as kaki, in amounts of 10 grams daily cures 

 guinea pig scurvy completely in 30 days. 



Among vegetables, raw greens and some of the roots and tubers 

 enjoy high reputation as antiscorbutics. 



Roots and Tubers. — The Swedish turnip, rutabaga or "swede" was 

 studied by Chick and Rhodes (1918), who found that the juice obtained 

 by filtering the freshly grated pulp through a muslin bag approximated 

 orange juice in antiscorbutic potency. A daily ration of 2.5 cubic centi- 

 meters of this juice fully protected a guinea pig against scurvy while 

 to afford approximately the same amount of protection required about 

 20 cubic centimeters of carrot juice and still more of beet juice. Raw 

 "swede" juice has therefore been widely advocated by the English 

 workers as an inexpensive source of vitamin C particularly in infant 

 feeding. : ' 



Delf (1925) found that rutabagas, like oranges and lemons, re- 

 tained their antiscorbutic properties in cold storage as long as they 

 remained in good condition. The stability of the frozen juice was not 

 as great, however, for the juice became entirely inactive after about 

 15 months. The emphasis by the English workers on yellow turnips or 

 rutabagas as antiscorbutics has led to the general impression that they 

 are much richer in vitamin C than white turnips, but it is doubtful 

 whether any such distinction holds. Scheunert (1929) has reported 

 almost as high values for early turnips as for rutabagas. In his experi- 



