238 THE VITAMINES 



were determined. This is true especially as regards quantitative 

 relationships. Chick and Dalyell (644) prepared another table with 

 regard to vitamine C, where the values are based on 100 for lemon 

 juice. 



Fresh orange juice or cabbage leaves 110 



Fresh raw orange juice 100 



Beet juice (swede) 60 



Green beans 30 



Sprouted fresh peas 30 



Carrot juice 7.5 



Red beet juice 7.5 



Meat juice (ox) 7.5 



Potato (cooked 39 minutes) 7.5 



Fresh cow's milk 1-1 . 5 



In our table, we were not satisfied to give only the vitamine value, 

 but also the nutritive value of the proteins of various origin. This 

 rubric will, perhaps, help us to demonstrate the difference between 

 the nutritive value of plant and animal protein, which may be of 

 importance in relation to the etiology of pellagra and war edema; 

 unfortunately, however, the data found on this subject are very 

 meagre. It appears to us not impossible that some protein substances 

 may contain adsorbed either a fourth vitamine, or a hitherto unknown 

 amino acid, essential to life. 



INFLUENCE OF HEATING AND COOKING ON THE VITAMINE CONTENT 1 



We owe to Schuffner and Kuenen (I.e. 56) the first data on this 

 subject of such practical importance. Studies on the stability of 

 vitamine B in foodstuffs were undertaken also by Grijns (I.e. 52). 

 Recently this field was systematically investigated by Chick and Hume 

 (645), using an improved technique. They studied the influence of 

 heat on vitamine B of wheat germ and found that a temperature 

 of 100C. for two hours has little influence, while a temperature over 

 120C. is quickly followed by destruction. Miller (646) found that 

 cooking and autoclaving (at 115C. for 45 minutes) had no effect oh 

 carrots and beans; this was confirmed by Whipple (647) for cab- 

 bage and onions. In the last two investigations the content of 

 vitamine B was determined by the yeast method already described 



1 A good review of the known data is found in the paper by Emmett and 

 Luros (I.e. 94). 



