26 MASS. EXPERIMENT STATION BULLETIN 417 



The Ratio of Ascorbic Acid, Riboflavin, and Thiamine in Raw and Pasteurized 

 Milk. (Arthur D. Holmes, Carleton P. Jones, Anne W. Wertz, and John W. 

 Kuzmeski.) While a considerable body of data is available concerning the 

 ascorbic acid, riboflavin, and thiamine content of milk, not a single report was 

 found of the assay of a milk for all three of these vitamins. Accordingly, 32 

 samples of milk produced by the college herd were assayed before and after 

 pasteurization. The average values obtained were ascorbic acid 19.7 mg., 

 riboflavin 1.51 mg., and thiamine 0.33 mg. per liter of raw milk; ascorbic acid 

 15.9 mg., riboflavin 1.48 mg., and thiamine 0.30 mg. per liter of the same milk 

 after pasteurization. 



The ratios of riboflavin, ascorbic acid, and thiamine were computed for both 

 the raw and the pasteurized milk. The raw milk contained 4.6 times as much 

 riboflavin as thiamine 13.1 times as much ascorbic acid as riboflavin, and 59.8 

 times as much ascorbic acid as thiamine; the pasteurized milk 4.9 times as much 

 riboflavin as thiamine, 11.0 times as much ascorbic acid as riboflavin, and 53.8 

 times as much ascorbic acid as thiamine. 



Ascorbic Acid, Riboflavin, and Thiamine Content of Mtlk as Influenced by the 

 Ration. (Arthur D. Holmes, Carleton P. Jones, and Anne Wertz.) It is generally 

 agreed that, under normal conditions, changing the cow's ration does not cause 

 any significant changes in the protein, fat, and mineral composition of the milk. 

 There is, however, a lack of agreement regarding the effect of changing a cow's 

 ration upon the vitamin content of her milk. Since it is generally believed that 

 young, rapidly growing grass is particularly rich in vitamins, this study was made 

 during the interval while the cows were being transferred from the winter ration 

 to green grass pasture ration. 



When the cows were changed from the winter ration to an early pasture of 

 rapidly growing grass, the volume of milk produced increased; the ascorbic acid 

 content of the milk decreased from 20.3 mg. to 19.1 mg. per liter; the riboflavin 

 decreased from 1.43 mg. to 1.26 mg. per liter; but there was no change in the 

 thiamine content. 



Effect of High- Temperature, Short- Time Pasteurization ott the Ascorbic Acid, 

 Riboflavin, and Thiamine Content of Milk. (Arthur D. Holmes, Harry G. Lind- 

 quist, Carleton P. Jones, and Anne W. Wertz.) Twenty lots of milk produced by 

 the college herd were pasteurized, with an Electropure pasteurizer, for 22 seconds 

 at temperatures ranging from 161° to 181 °F. Samples of the milk taken just 

 before and immediately following pasteurization were assayed for ascorbic acid, 

 riboflavin, and thiamine. The average values obtained were 16.4 mg. per liter 

 of ascorbic acid for the raw and 16.6 mg. for the pasteurized milk; 1.50 mg. of 

 riboflavin for the raw and 1.50 mg. per liter for the pasteurized milk; and .36 mg. 

 of thiamine for the raw and .35 mg. per liter for the pasteurized milk. Hence, 

 considered from a practical standpoint, milk pasteurized by this type of high- 

 temperature, short-time procedure has as satisfactory ascorbic acid, riboflavin, 

 and thiamine content as before pasteurization. In contrast, there were significant 

 vitamin losses when milk was pasteurized at 145 °F. for thirty minutes. 



Ascorbic Acid, Riboflavin, and Thiamine Content of Chocolate Mill<. (Arthur 

 D. Holmes, Carleton P. Jones, Anne W. Wertz, and W. S. Mueller.) The term 

 chocolate milk is very misleading since this product is very frequently made with 

 cocoa. In this study both the American-process and the Dutch-process (alkali) 

 cocoa were used. 



Sixteen samples of chocolate milk were prepared by mixing 30 cc. of cocoa 

 syrup and 240 cc. of freshly pasteurized milk. The pasteurized milk contained 



