248 AKNTJAL REPORT SMITHSONIAN INSTITUTION, 1941 



Other fruits that may be considered important from the stand- 

 point of vitamin-C content are strawberries, blueberries, and cran- 

 berries. Among the vegetables, peppers are outstanding in the quan- 

 tity of vitamin C they contain. Cabbage and other members of the 

 cabbage family, cauliflower and brussels sprouts, and turnips and 

 rutabagas also contain large amounts. Vitamin C occurs in fairly 

 high concentration in all leaves such as spinach, collards, turnip 

 greens, and watercress. 



Variation in vitamin content according to variety has been studied 

 more extensively with respect to vitamin C than for any of the other 

 vitamins. Rather wide varietal differences have been shown for 

 apples, tomatoes, oranges, and cabbage. In the case of oranges sev- 

 eral other factors are known to influence vitamin-C content, making 

 varietal differences as studied of lesser importance. Fully ripe fruit 

 contains more of the vitamin than partially ripe fruit, and that ex- 

 posed to sunlight is richer than that from the shaded side of the tree. 

 The vitamin-C content of a given variety of orange decreases pro- 

 gressively as the season advances although this change is less pro- 

 nounced for some varieties than others. Conditions of cultivation 

 also have an influence, but these are not as well defined as other 

 factors. The extent of differences that exist in the vitamin-C content 

 of oranges may be illustrated by values obtained in the Bureau of 

 Home Economics on a dozen oranges examined individually. These 

 oranges were of uniform size and appearance and were purchased 

 at one time and came from a single bin in a store in Washington, 

 D. C. The vitamin-C content ranged from 24 to 60 milligrams of 

 ascorbic acid per 100 milliliters of juice. 



Factors other than variety that may influence vitamin-C content 

 have also been studied with apples and tomatoes. With apples, size 

 is significant. In this fruit the vitamin is concentrated in the skin 

 and in the flesh just under the skin. Since the proportion of skin to 

 flesh is greater in small than in large apples, a small apple contains 

 more vitamin C in proportion to its weight than a large one. In 

 tomatoes there is a gradual increase in vitamin-C content as the fruit 

 matures while during the actual process of ripening there may be a 

 decrease. 



Milk and meats should not be considered significant sources of 

 vitamin C. Milk as it comes from the cow contains an appreciable 

 amount, but this is inactivated rapidly as the milk stands. Meats are 

 not important sources because whatever vitamin C they contain is 

 destroyed during cooking. Eggs do not contain vitamin C. 



Vitamin C is not present in fats and oils since it is soluble in water 

 and not in fats. 



