Effect of Cooking upon Vitamin in Cabbage. 155 



(b) From these data it is shown that widely divergent curves 

 of acidity may be plotted which depend entirely upon the experi- 

 mental error of the method and not upon the subject's gastric 

 condition. 



(c) The inadequacy of the titration method and the importance 

 of hydrogen ions and buffer salts in measuring gastric acidity is 

 indicated. 



3. A subject who could regurgitate his total gastric contents 

 at will, was given the test meal on different days and the total 

 contents were regurgitated at different intervals from the time of 

 ingestion to the test meal. The curve of acidity plotted in this 

 manner differed radically from the curve obtained in the usual 

 manner. Furthermore, discrepancies were noted between the 

 acidity of an aliquot removed immediately prior to regurgitation 

 and the acidity of the total gastric contents. 



Results obtained by the Rehfuss method may be more validly 

 interpreted if: (a) the analysis is repeated until a satisfactory 

 agreement in curves is obtained ; (b) the tube is kept at a constant 

 level; (c) aliquot fractions are large; (d) little saliva is swallowed; 

 (e) acidity is measured in terms of hydrogen ions and buffer salts. 



74 (1821) 



The effect of cooking upon the antiscorbutic vitamin in cabbage. 



By WALTER H. EDDY, E. SHELOW and R. A. PEASE. 



[From the Department oj Physiological Chemistry and the 

 Department of Foods and Cookery, Teachers College, 

 Columbia University, New York City.] 



The present report is one of a series of studies undertaken to 

 determine the effect of the new cooking implement known as the 

 pressure cooker upon the vitamin content of such foods as are 

 adapted to preparation in that device. The cooker also affords 

 in its manipulation an opportunity to throw light on the response 

 of vitamins to certain combinations of destructive influences that 

 are absent or different from those met in older methods of cookery. 

 The present study is confined to a comparison of the effects of 

 pressure versus open kettle cooking on the vitamin C content of 

 cabbage. 



