190 THE VITAMINS 



Lewis (1919) concluded that, with a basal diet adequate in all 

 respects except vitamin C, from 10 to 15 grams of raw banana per 

 guinea pig per day sufficed for growth and protection against scurvy. 

 Givens, McClugage and Van Home (1921) considered 10 grams to 

 be the minimum protective dose and the same amount was reported by 

 Jansen and Donath (1925) for two varieties of Indian banana. Eddy 

 (1926) considered 5 grams of banana to be the minimum protective 

 dose and from 8 to 10 grams the optimum dose for growth stimulation 

 as well as scurvy prevention in guinea pigs. In the senior author's 

 laboratory raw bananas have appeared to contain about one-third as 

 much vitamin C as oranges or tomatoes. Eddy and Kellogg (1927) 

 found that bananas baked in the skin retain their antiscorbutic proper- 

 ties better than when baked without the skin, probably on account of 

 the protective action of the skin against oxidation. They reported at 

 this time the cure of scurvy in an eight months' old baby by a banana- 

 milk mixture made by whipping 2(X) grams of ripe, raw banana into 

 570 cubic centimeters of milk. This was fed in 120 cubic centimeter 

 portions every four hours with no resulting digestive disturbances. 



Fresh raw apples are in general about half as rich in vitamin C 

 as bananas, and there may be considerable loss of this vitamin when 

 apples are kept in storage or cooked by the usual household methods. 

 Kohman, Eddy and Carlsson (1924) found that apples held in cold 

 storage from October to March showed a gradual deterioration in vita- 

 min C content, that very little of the vitamin could be demonstrated in 

 freshly prepared apple sauce, baked apples, or apples canned without 

 any special treatment, but that there was no appreciable loss in vitamin 

 C in apples canned according to the commercial practice of allowing 

 them to stand in salt solution long enough to exhaust their respiratory 

 oxygen before the usual processing. With this provision, the time of 

 processing within the limits followed in commercial practice was imma- 

 terial. These findings were considered to indicate that the amount of 

 respiratory oxygen in the cells of apples, and presumably other fruits, 

 is an important factor in the destruction of vitamin C not only in can- 

 ning but in storage. 



A recent investigation by Bracewell, Hoyle, and Zilva (1930) of 

 the vitamin C content of a number of varieties of apples grown in 

 England and several of the colonies showed wide differences according 

 to the variety. Of all the varieties tested, the English cooking apple 

 known as Bramley's Seedling was found to be decidedly the most 

 active, complete protection against scurvy being secured with 3 grams 

 daily. The relatively high activity of this particular apple appeared not 



