Dec. i, 1920 Some Changes in Florida Grapefruit in Storage 359 



sugars a 50-cc. aliquot was pipetted into a 100-cc. volumetric flask, the 

 sucrose inverted by adding 5-cc. of concentrated hydrochloric acid and 

 allowing it to stand overnight at room temperature. This solution was 

 made up to volume, neutralized, and the reducing substance in it was 

 determined. 



Matthews's modification of Bertrand's method (7, p. 994) was followed 

 in the determination of the sugars. The sugars were calculated as dex- 

 trose according to Munson and Walker's tables (10). 



PRELIMINARY EXPERIMENTS, 191 7-18 



Table I shows the results obtained from several experiments in which 

 fruit was placed in the incubator maintained at 86° F\ In these experi- 

 ments a sample consisting of six or more fruits was analyzed when the 

 fruits were placed in the incubator, and analyses were made at the 

 dates indicated in the first column. In experiment 2 fruit of the same 

 lot as that used in experiment 1, which had been kept in cold storage 

 since November 28, was placed in the incubator on January 6. The 

 analyses on this latter date give data as to the effect of storage at 32 

 on the acid and sugar content of the fruit. The change in the acid- 

 solids ratio of this fruit maintained at 86° for 15 and 28 days is shown 

 in the table. 



Table I. 



-Changes in the composition of Silver Cluster grapefrui t during storage att 

 as indicated by the change in acidity and sugar content of juice 



F. 



EXPERIMENT I 



Date sampled. 



Nov. 28, 1917 

 Dec. 8, 1917. 



Jan. 5, 1918. 



Acid as 

 citric. 



Per cent. 

 I. 16 

 I. 14 



1. 09 



Soluble 

 solids 

 (Brix). 



9-i5 

 9.81 



10.97 



Acid- 

 solids 

 ratio. 



7-9 

 8.6 



10. 06 : 1 



Sugar as dextrose. 



Reducing. 



Per cent. 



2-95 



3-03 



3-49 



Per cent. 

 2.76 

 2.79 



2-59 

 2.28 



Total. 

 Per cent. 



5-7i 

 5- 77 

 5. 62 



5-77 



EXPERIMENT 2; FRUIT PLACED IN INCUBATOR 



Jan. 6, 1918. 



Jan. 21, 1918 

 Feb. 3, 1918. 



1. 14 



•83 

 .76 



8-95 



9-83 

 9.29 



7.8 : 1 



11. 8 : 1 



12. 2 : 1 



2. 90 

 2.87 



2.68 

 2-59 



5-58 

 5-46 



From Table I it is evident that there is a decrease in acidity when the 

 fruit is stored at warm temperatures, while there is little, if any, de- 

 crease in the total sugar content of the juice. The reducing sugar is 

 increased somewhat, but there is a corresponding decrease in the cane 



