146 



Journal of Agricultural Research 



Vol. XVII, No. 4 



this point tlirough all of the curves. Vertical lines are now dropped 

 from the points of intersection to the base line. The times in hours 

 required at the different temperatures to bring the sugar loss to this point 

 are read off on the base line (see fig. i). The procedure was repeated 

 for all the percentages given on the ordinate. 



The relative rates of sugar loss at the different temperatures are ex- 

 pressed in Table IV as the reciprocals of the times in hours required to 

 bring the process to five different stages. The temperature coefficients 

 were obtained from these reciprocals. The results at 40° C. were not 



10 



20 



« 30 



40 



50 



60 



70 



24 



48 



H U R.S 



72 



96 



Fig. I. — Depletion of total sugars in green sweet com during consecutive 24-hour periods of storage at 

 different temperatures. The ordinates are given by the numbers on the left of the figure and represent 

 the loss of sugar expressed as percentages of the initial sugar, which was 5.91 per cent, wet weight. 



included in the foregoing calculation as there was evidently destruction 

 of the enzymes or other alteration in the system by the high temperature. 

 Some of the cur\^es for the sugar loss, expecially those for sucrose, 

 approach true logarithmic curves; and satisfactory constants were 

 obtained for most of the storage period by applying the simple uni- 

 molecular equation. During the latter part of the period there was a 

 falling off in the velocity constants, due no doubt to the counter reaction. 

 The simple uni-molecular equation assumes that the reaction proceeds 

 to completion or so near completion that the speed of the counter may 

 be ignored. However, as Osterliout has shown in the paper previously 



