THE COMPOSITION OF FRUITS 7 



becoming much darker on keeping. When shghtly cooled it 

 forms a concrete mass, due to the separation of small ocicular 

 crystals, which consist of a paraffin hydro-carbon. It 

 possesses in a high degree the characteristic, fragrant odor 

 of fresh apples. Besides the esters mentioned, it has been 

 found to contain, Ipy, specific tests, small amounts of ac- 

 . H^f ^ etaldehyde and furfural. ■/ The jaeld of oil from the parings 

 of the Ben Davis apple was 0.0035 per cent, and that from 

 the more odorous crab apple 0.0043 per cent, which cor- 

 responds to about 0.0007 and 0.0013 per cent respectiv^ely of 

 the entire ripe fruit. " 



The esters referred to above are "the amyl esters of 

 formic, acetic, and caproic acids, with a veiy small amount 

 of the capiylic ester and a considerable proportion of ac- 

 etaldehyde. " 



Amyl valerate, which is usually referred to as "apple oil," 

 has not been identified as present in the apple. 



7. Quality in apples. — As mentioned above, certain 

 components of the apple give it flavor or eating quality. 

 The term is used rather loosely in pomology, referring 

 sometimes to the dessert quality, sometimes to the cooking 

 property, and again to shipping and market quality. 



Shaw ^ has analyzed apple varieties to determine the 

 ingredients which are associated with dessert quality, and 

 the two apples used for illustrating high and low quality are 

 the Grimes and Ben Davis. The following figures show 

 the relative amounts of the important ingredients, each 

 being the average of eleven determinations. 



1 Shaw, J. K. Proc. Amer. Soc. Hort. Sci. 1912. p. 29. 



