376 



RIBOFLAVIN 



TABLE II— Concluded 



" For canned, reduce by one-half. 



blanching operations.^" ^ These losses are usually less than 20%, and they 

 can be further minimized if the cooking fluids are consumed. 



Losses of riboflavin due to exposure to light during cooking may prove 

 to be an important economic loss. Cheldelin et alJ have shown large losses, 

 up to 48 % , incurred in the cooking of eggs, milk, and pork chops in uncov- 

 ered dishes under conditions where there was no loss of riboflavin when 

 cooking dishes were covered. The loss in milk*'^" which is allowed to stand 

 in glass containers on the consumer's doorstep may be as high as 85 % after 

 2 hours exposure to bright sunlight. ^^ This may be compared with practic- 



» H. L. Mayfield and M. T. Hedrick, J. Am. Dietet. Assoc. 25, 1024 (1949). 

 * J. M. Mclntire, B. S. Schweigert, L. M. Henderson, and C. A. Elvehjem, /. Nutri- 

 tion 25, 143 (1943). 

 5 J. R. Wagner, F. M. Strong, and C. A. Elvehjem, Ind. Eng. Chem. 39, 985 (1947). 

 « W. A. Krehl and R. W. Winters, /. Am. Dietet. Assoc. 26, 966 (1950). 



7 V. A. Cheldelin, A. M. Woods and R. J. Williams, J. Nutrition 26, 477 (1943). 



8 R. R. Williams and V. H. Cheldelin, Science 96, 22 (1942). 



9 J. A. Ziegler, /. Am. Chem. Soc. 66, 1039 (1944). 



10 W. J. Peterson, F. M. Haig, and A. O. Shaw, ./. Am. Chem. Soc. 66, 662 (1944). 



11 A. D. Holmes and C. P. Jones, J. Nutrition 29, 201 (1945). 



