44 MASS. EXPERIMENT STATION BULLETIN 339 



an increase in iodine concentration. There was a definite decrease in the per- 

 oxidase activity of milk with increasing amounts of iodine added. In toluene- 

 preserved samples, the catalase activity of milk increased slightly up to a con- 

 centration of 100 p. p.m. of added iodine, but beyond this point catalase activity 

 decreased. In non-preserved samples, there was a definite decrease of catalase 

 activity with an increase in iodine concentration. The amylase activity of milk 

 was inhibited by an increase in iodine concentration. The lipase, protease, 

 and oxidase are present in milk in such minute amounts that it has not been 

 possible to make an accurate study of the effect of added iodine on them. 



Iodine Tolerance of Albino Rats. (J. H. Frandsen, W. S. Mueller, and 

 Myer Glickstein.) A preliminary feeding experiment with albino rats is under 

 way, to determine the iodine tolerance of rats when fed varying doses of iodine 

 in milk and in water. The rations were so calculated as to give approximately 

 the same food constituents, except that one group received iodine in milk and 

 the other group received its supply of iodine in water. Only tentative con- 

 clusions can be drawn at this time. 



The rats receiving iodine in milk averaged slightly more in weight than those 

 receiving it in water. Studies on the possible effect on the reproductive ability 

 of the rats are now in progress. 



Pasteurized versus Buddeized Milk. (J. H. Frandsen, W. S. Mueller, 

 and Myer Glickstein.) Buddeized milk is raw milk to which hydrogen peroxide 

 has been added in amounts sufficient to destroy bacteria. In this experiment 

 pasteurized and Buddeized milk were fed to groups of rats. So far there is 

 little indication of difference between results obtained by the two milks. The 

 work will be continued. 



A Study of the Efficiency of Water Heaters, Electric Sterilizers, and 

 Electrically Operated Cooling Tanks. (J. H. Frandsen, H. G. Lindquist, 

 and Myer Glickstein.) During the year attention has been given largely to a 

 study of the efficiency and economy of water heaters and electric sterilizers. 

 Preliminary work indicates that electric units for the sterilization of dairy 

 utensils are efficient in reducing bacteria counts, and are economical wherever 

 electricity is available at low cost. Most of these sterilizers are of simple con- 

 struction and easy to operate. Data are being assembled for publication. 



A Study of the Possibilities of Milk, Cream, and Plastic Cream in 

 the Development of New Products such as Combinations with Honey, 

 Fruits, Cheese, and other Flavors of Various Kinds. (J. H. Frandsen 

 and Myer Glickstein.) New products such as combinations with certain fruits, 

 nuts, and some of the well-known hard and semi-hard cheeses are being made 

 and studied. 



A Study of the Changes that Occur in the Storage of Frozen Sweet 

 Cream. (H. G. Lindquist.) This project is being continued, using such 

 materials as sodium caseinate and Dariloid to prevent frozen stored cream from 

 oiling off when thawed. 



