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JOURNAL OF AGRTOTOAL RESEARCH 



Vol,. XX Washington, D. C, March i, 1921 No. 11 



EVALUATION OF CLIMATIC TEMPERATURE EFFI- 

 CIENCY FOR THE RIPENING PROCESSES IN SWEET- 

 CORN 



By Charles O. Appleman, Plant Physiologist, and S. V. Eaton, former Assistant 

 Plant Physiologist, Laboratory of Plant Physiology, Maryland Agricultural Experiment 

 Station 



INTRODUCTION 



Green sweetcorn for table use or packing into cans is picked while the 

 ripening processes are actively in progress. Since these processes greatly 

 change the chemical composition of the corn, it is obvious that the ears 

 must be picked as nearly as possible at the stage of ripening that will 

 furnish the most desirable quality. There is some difference of opinion 

 in regard to the chemical composition that gives the most desirable 

 quality to sweetcorn, especially for packing into cans. Attention 

 is usually focused upon sugar content, as sweetness is a desirable quality 

 of sweetcorn and, morever, the flavor appears to be associated with the 

 sugar content. This relationship may be merely a parallelism, but it 

 is certainly true that corn acquires a decided flat taste after the sugar 

 is reduced to low content either on the stalk or in storage. The fore- 

 going statement does not necessarily apply to naturally low sugar content 

 in certain varieties or to the same variety grown under different con- 

 ditions. 



The percentages of starch and crude fiber are claimed by some to be of 

 equal if not of even greater importance than the sugar content. The 

 percentage of starch must be sufficiently high to give body to the corn, 

 while the amount of crude fiber must be kept as low as possible. Since 

 the starch and crude fiber increase at the expense of the sugar, the most 

 desirable stage for picking corn would seem to be a wise compromise 

 between sugar content and other constituents. 



The present paper deals with the chemical changes in sweetcorn 

 during ripening and the effect of climatic temperature on rate of these 

 changes. An attempt has also been made to evaluate the climatic 

 temperature efficiency for these processes and to make the results of 

 some practical value as a guide for picking corn in different localities 

 and in different seasons in the same locality. 



Journal of Agricultural Research, Vol. XX, No. xi 



Washington, D. C Mar. i, 1921 



yrx Key No. M6I.-3 



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