PART III. 



CHEMICAL CHANGES IN APPLES DURING 



STORAGE. 



BY FRED W. MORSE. 



The apple is a living organism when picked from the tree, 

 and remains so after picking for days, weeks, and even 

 nnonths, under favorable conditions. This life is maintained, 

 however, at the expense of its own constituents, and the apple 

 is really undergoing a slow form of dissolution until decay 

 attacks and destroys it, leaving only the fibrous portions of 

 its structure and the seeds. 



The process of dissolution is a continuous one, and is mani- 

 fested by a respiratory action, during which water and carbon 

 dioxide are exhaled as in the breathing of animals. At the 

 same time there is a transformation and destruction of the 

 constituents of the fruit, in order to produce these products of 

 respiration. 



The change in constituents of the apple during the earliest 

 periods after picking has been called " after-ripening," and 

 it has been fully studied by Kulisch* in Germany and 

 Browne I in this country. 



In brief, these changes have been shown to be mainly a 

 transformation of starch into cane sugar in the first stage after 

 picking, next the change of the cane sugar into invert sugar, 

 and finally a slow decrease in the total quantity of sugars. 

 At the same time, from the first, the acid in the fruit gradu- 

 ally grows less in amount, there being most in the unripe 

 fruit. 



The object of our investigations was to determine the effect 



* Bied. Centr. Agriculturchem, 22, 625. 

 t Bull. 58, Penn. Dept. Agr. 



