24 BULLETIN 850, U. S. DEPARTMENT OF AGRICULTURE. 



in the case of ripened turnings is 6.78, compared with 6.34 in vine- 

 ripened fruit. This signified that the former should be comparatively 

 sweet and less pronouncedly acid, as was indeed true. The facts 

 brought out indicate that there is less chemical difference, between 

 turning and vine-ripened fruit than there is between commercially 

 ripened green fruits and the latter. Differences in chemical compo- 

 sition between vine-ripened fruit and commercially picked green to- 

 matoes ripened in the laboratory, exposed to air and light, are not 

 sufficient to account for the marked differences in flavor and palata- 

 bility between commercially ripened fruit and normal fruit. This 

 conclusion was confirmed by taste comparisons. 



EFFECT OF LACK OF VENTILATION ON RIPENING. 



Since the differences due to ripening after picking with normal 

 exposure to the air were obviously insufficient to account for the in- 

 feriority of Florida tomatoes after shipment, it seemed to be clearly 

 indicated that the cause of the difficulty might well be lack of venti- 

 lation during commercial ripening. As already stated, the fruits 

 are wrapped before packing for shipment, and it seemed not unlikely 

 that the paper used might appreciably retard gas exchange and thus 

 modify the course of ripening. 



In order to test the hypothesis that wrapping plays an important 

 part in influencing the composition and flavor of tomatoes, it was 

 deemed necessary to analyze tomatoes which were ripened in a non- 

 ventilated chamber and to compare the results with those obtained 

 with wrapped fruit. Comparisons were made between (1) tomatoes 

 commercially picked and ripened without ventilation, (2) commer- 

 cially picked and ripened, wrapped with one paper, (3) commercially 

 picked and wrapped with three papers, (4) commercially picked and 

 ripened unwrapped at room temperature, (5) turnings ripened un- 

 wrapped at room temperature, and (6) vine-ripened fruit. All of the 

 fruit used for the above comparisons was obtained at the same time. 

 A box for the green fruit ripened with no ventilation was made of 

 composition board about a quarter of an inch thick. The approxi- 

 mate size was a little less than 1 cubic yard. All corners were sealed 

 with adhesive tape and the door was made by cutting it from the 

 board and hinging it on. The total exclusion of air from the interior 

 of the chamber of course was not secured, but the degree of non ven- 

 tilation obtained was complete enough for the experiment, as shown 

 by the fact that at times the oxygen content of the chamber would 

 not support an alcohol flame. Six baskets of tomatoes (approxi- 

 mately 125 fruits) were allowed to remain in this chamber, which was 

 heated with one electric bulb, until they showed a red color. They 

 were then removed and sampled by taking portions from 15 to 20 

 fruits. It required 11 days for the color to appear. Other fruits 



