VITAMINS Ol" CRANBERRIES 



HISTORICAL 



No thorough imestigatioii of the vitamin content of cranberries has been re- 

 ported. In fact, no work has been reported on vitamins A,B,D, and (i. MacLeod 

 and Booher (22) reported the American cranberry as being a poor source of vita- 

 min C. However, this conclusion is open to criticism, first, because the cran- 

 berries had been in storage for seven or more months and, as will be demonstrated 

 in this paper, had undoubtedly lost much of their original vitamin C content; and 

 second, because the experimental animals did not consume their full portion of 

 fruit plus basal ration. Naeslund (2S) investigated the vitamin C content of V. 

 Vitis-Idaca in Norway and found them to be weakly antiscorbutic. He estimated 

 the protective portion of fruit or freshly expressed juice to be more than 50 grams, 

 with no difference in potency between the whole berry and its expressed juice, 

 losing the same fruit, Laland (21) was unsuccessful in his attempts to isolate nar- 

 cotine, believed by Rygh and his coworkers (31,32,33) to be the precursor of 

 vitamin C. However, Dalmer and Moll (9) and Briiggemann (6) were unable to 

 verify Rygh's results; and recently Svirbely and Szent-Gyorgyi (40), and also 

 King and Waugh (18) have proved beyond question that vitamin C is closely 

 related to or identical with hexuronic acid.' 



After the completion of the vitamin C studies reported in this paper, a recent 

 Russian investigation on V. Oxycoccus came to our attention. Bogoliubova (3) 

 found that 2.5 grams of these wild cranberries, after storage for three months near 

 the freezing point, fully protected guinea pigs from scurvy during a seven weeks' 

 test period. However, cranberries which had lain under snow all winter or which 

 had been alternately frozen and thawed, showed no protective action. Similarly, 

 dried or fermented cranberries lost their vitamin C potency. She believes that 

 cranberries are an important antiscorbutic in all northern countries and states 

 that the value of cranberries for the treatment of scurvy in Russia was known as 

 early as 1848. Mention is made that sailing vessels used cranberry juice as an anti- 

 scorbutic many years ago. 



Bogoliubova also noted the absence of xerophthalmia in her guinea pigs, and 

 since the oat diet was deficient in vitamin A, concluded that cranberries contained 

 some of this vitamin. However, no data were presented. 



The resistance of vitamin C to heat and oxidation is materially increased by 

 high acidity, and the cranberry is characterized by a high acidity which averages 

 about 2.3 per cent (calculated as citric acid). According to Nelson (29), the 

 fi.xed acids are 88 per cent citric and 10 per cent malic. Mason (24) detected ben- 

 zoic acid in the cranberry; this finding was verified by Griebel (17), and also in 

 this laboratory where it was found that the benzoic acid content of 25 varieties 

 ranged from 0.027 to 0.098 per cent. It is probable that the good keeping qualities 

 of fresh and preserved cranberries are in part due to the presence of free or com- 

 bined benzoic acid. The presence of quinic acid in cranberries was presumed by 

 Blatherwick and Long (2) and by Quick (30). Kohman and Sanborn (20), Morse 

 (27), and Fellers, Redmon and Parrott (15), have gathered further positive evi- 

 dence of the presence of 0.38 to 1.03 per cent of quinic acid in cranberries. Unlike 

 benzoic acid, quinic acid has no significant antiseptic properties against micro- 

 organisms. 



^Recent investigations by Hahn (Ztschr. Untersuch. Lebensmtl. 61:369-411, 515-611, 1931) 

 show that raw or cooked mountain cranberries are very poor sources of vitamin C 



