Dec. : 



Changes in Composition of Ripening Bananas 



197 



changes with the changes in rate of respiration. The results show that the 

 most rapid starch hydrolysis occurs at the time when the respiration 

 rate is greatest. The following is a detailed account of the work. 



The fruits from a large bunch of green bananas were cut from the 

 stem by first cutting off the "hands" and then separating the indi\adual 

 fruits, finally removing from each fruit the small piece of adhering stem, 

 cutting where the stem was most constricted, as in sampling bananas in 

 previous studies. A few drops of sticky, turbid juice oozed from each 

 banana, and care was taken not to allow the fruit surfaces to become 

 wet with it. Fruits from the inside and the outside of each "hand" 

 were divided as evenly as practicable into nine different lots, each lot 

 receiving fruits from all parts of the bunch, and consisting of from 

 13 to 17 fruits. The lots were weighed and placed in the humidity 

 chamber on the afternoon of May i. The analysis of the first lot was 

 made upon the afternoon of the following day, immediately after the 

 determination of its respiratory activity. The remaining lots were 

 successively analyzed at intervals of from one to three days, except the 

 ninth lot, which was kept longest, and spoiled. See Table V. 



Table V. — Composition of detached bananas during ripening in the humidity chamber 



COMPOSITION EXPRESSED IN TERMS OF PERCENTAGES OF PEEI. AXD PULP OF THE BANANAS BEFORE AND 



AFTER RIPENING 



Part of fruit. 



Inter- 

 val la 

 humid- 

 ity 

 cham- 

 ber. 



Loss in 

 weight 

 in hu- 

 midity 

 cham- 

 ber. 



Percent- 

 age of 

 whole 

 fruit. 



Composition of peel or pulp. 



Solids. 



Alco- 

 hol-in- 

 soluble 

 soUds. 



Total 



sugar 



Starch. 



1912. 



May z 



3 



PEEL. 



Green bananas 



Slightly yellowing bananas. 



do 



Yellow bananas 



...do 



... do 



...do 



Brown bananas 



PULP. 



Green bananas 



Slightly yellowing bananas. 



...do 



Yellow bananas 



...do 



....do 



...do 



Brown bananas. 



Days. 



1.66 

 2.47 

 3-67 

 6.48 

 7.83 

 8-39 

 10. 56 

 11-32 



1.66 

 2.47 

 3-67 

 6.48 

 7-83 

 8.39 

 lo. 56 

 11.32 



38.22 



37-54 

 35-41 

 32-57 

 30-88 

 29.35 

 27-95 

 26. 26 



61.77 

 62.45 

 64.58 

 67.42 

 69. 12 

 70.65 

 72.05 

 73-74 



89. 



72.47 

 72.37 

 72.44 

 73-26 

 73-45 

 74-63 

 75-72 

 77-02 



10-54 

 "•39 

 11.36 

 13- 16 

 14. 10 

 14.92 

 15-75 

 16.68 



27-53 

 27-63 

 27-56 

 26-74 

 26-55 

 25-37 

 24.28 

 22.98 



6.83 



8.52 

 6.J8 

 6.09 

 6.67 

 7.08 

 7-57 

 8.12 



21-95 

 16.46 

 11.04 

 5. 82 

 3-89 

 3- 13 

 2.88 

 3-17 



1-39 

 2. 16 



2.91 

 3- 64 

 3-89 

 3-98 

 4.07 

 4- 38 



4-35 

 9-65 

 IS- 00 

 19.6s 

 20.08 

 20.61 

 20.05 

 18.21 



3.28 

 2-93 

 2. II 

 1.63 

 1.69 

 1.82 

 i.8« 

 1.84 



19.01 

 13-96 

 8.62 

 3-65 

 I- 73 

 I- IS 

 •87 

 1. 01 



COMPOSITION E.XPRESSBD IN TERMS OF PERCENTAGE OF THE WHOLE GREEN BANANAS 



May 



PEEL. 



Green bananas 



Slightly yellowing bananas . 



do 



Yellow bananas 



do 



...do 



do 



Brown bananas 



• 72 



• so 

 .48 



• 49 

 ■47 

 •43 



