Effect of Heat on Vegetables. 



53 



when added to the dietary of hay, oats and water, were fully 

 capable of protecting the animals. It is evident, therefore, that, 

 in a consideration of vegetables as a foodstuff, we must take into 

 account the factor of freshness. In dietetics this difference is 

 intensified by the fact that older vegetables are tougher and there- 

 fore require and receive more prolonged cooking, thus further 

 lessening their antiscorbutic value. The water in which the vege- 

 tables were cooked possessed little or none of the accessory factor, 

 although 40 c.c. per capita were fed to the guinea-pigs; the animals 

 did not, however, lose weight as rapidly as those receiving tap 

 water. 



In a previous communication it was shown that 5 c.c. of canned 

 tomatoes is sufficient to protect a guinea-pig from scurvy. If 

 such tomatoes are boiled for five minutes, their potency is slightly 

 diminished, so that they should not be subjected to cooking when 

 employed as an antiscorbutic for infants. Their efficacy was not 

 diminished by rendering them slightly alkaline to phenolphthalein. 

 Orange juice, which had been made n/20 alkaline to NaOH, was 

 found to be just as potent as in the acid state. The tomato as 

 well as the orange juice was given by a pipette one half to three 

 quarters of an hour following alkalinization. Neither of these 

 antiscorbutics, however, will retain their power long after they 

 have been rendered alkaline. In judging of the effect of alkalini- 

 zation or of heat, it is highly important to consider the length of 

 time to which the antiscorbutic has been subjected to this in- 

 fluence. 



33 (1408) 



Studies of saliva in its relation to the teeth. 



I. On the Normal Composition of Saliva. 



1 . Does normal saliva contain uric acid {urate) ? 



By G. A. Lowenstein and William J. Gies. 



[From the Biochemical Laboratory of Columbia University, College 

 of Physicians and Surgeons, New York.] 



By the use of a slight modification of the Folin-Benedict 

 method for the determination of uric acid in blood, we definitely 

 established the presence of uric acid (urate) in saliva. The average 



