RIPENING, STORAGE, AND HANDLING OF APPLES 



43 



held. In nearly all varieties during both seasons' work, fruit held 

 at 70° or 85° F. was lower in acidity when fully ripe than that held at 

 lower temperatures. There is, however, not a sufficiently consistent 

 variation in the titratable acidity to be certain of the general effect 

 of temperature upon the amount of this reduction. A summary of 

 all of the data presented indicates that, in general, apples held until 

 soft ripe at temperatures of 70° or 85° will be somewhat lower in 

 acidity than those held at 40° to 50° and that fruit held at 30° or 

 32° may also be somewhat lower in acidity than that held at inter- 

 mediate temperatures. It seems probable that the acidity changes 

 are associated with the respiration rate and the quantity of oxygen 

 available in the tissues, and consequently they will vary with differ- 

 ent varieties and with the same variety grown under widely varying 

 conditions. As a result, it is impossible to make any generalizations 

 except that at all the temperatures there is a distinct reduction in 

 titratable acidity between the time the fruit is picked and the time it 

 is soft ripe. In general, it appears that the least reduction in acidity 

 occurs when the fruit is ripened at temperatures of 40° to 60°. 



Table 4. — Length of time in storage, pressure test at end of storage period, 

 and chemical composition of apples held at various storage temperatures 











Percentage of sugar 



Titratable 





Storage 

 tempera- 



Time in 

 storage 



Pressure 

 test 







acidity 



Variety, station, and season 







as malic 





ture (°F.) 



(days) 



(pounds) 



Total 



Reducing 



acid 

 (per cent) 





f « 







13.45 



10.47 



7.62 



0.73 





70 



11 



8.10 



10.77 



7.88 



.58 





60 



15 



8.05 



11.20 



7.90 



.63 



Mcintosh, Rosslyn, Va., 1924-25 



50 

 40 



21 

 39 



8.40 

 9.10 



10.91 

 11.34 



7.69 

 8.14 



.68 





.68 





36 



62 



9.10 



10.84 



8.30 



.62 





32 



87 



9.00 



11.34 



9.24 



.50 





30 



f C 1 ) 



108 

 



9.50 

 18.00 



11.26 



9.22 



.40 

 1.01 





70 



18 



10.35 



12."26" 



9.~30~ 



.88 





60 



21 



10.45 



12.74 



9.42 



.88 



King David, Rosslyn, Va., 1924-25 



50 

 40 



24 

 48 



10.05 

 10.50 







.95 







.93 





36 



120 



10.55 







.78 





32 



180 



11.80 







.71 





30 



180 



11.60 







.71 





I (2) 





11.00 







.69 





85 



"T 



8.00 



"~~12.~88~ 



9.~6T 



.47 





70 



6 



8.10 



12.59 



8.96 



.54 



Jonathan, Yakima, Wash., 1923-24 



60 

 50 



8 

 11 



7.90 

 8.25 



12.38 

 12.38 



8.59 

 8.61 



.52 

 .56 





40 



17 



8.55 



12.67 



9.16 



.55 





36 



43 



8.35 



12.13 



8.86 



.56 





32 



48 



8.65 



12.67 



8.96 



.58 





r (2) 



33 



15.90 



13.83 



7.22 



.55 





85 



6 



7.25 



15.05 



7.69 



.45 





70 



8 



8.75 



15.05 



7.66 



.47 



Grimes Golden, Rossiyn, Va., 1923-24 



60 

 50 



13 

 25 



9.15 

 9.55 



14.96 

 15.00 



7.68 



7.87 



.45 

 .53 





40 



33 



9.10 







.46 





36 



55 



9.15 



15."65" 



8.~l6 



.49 





I 32 



81 



9.40 



15.14 



8.06 



.55 





r w 







17.20 



9.38 



6.56 



.55 





70 



17 



9.35 



11.34 



6.98 



.38 





60 



21 



10.5 



11.80 



7.12 



.42 



Grimes Golden, Rosslyn, Va., 1924-25 



50 

 40 



24 

 50 



10.25 

 9.5 



11.70 

 11.62 



7.36 

 8.10 



.49 

 .46 





36 



74 



9.25 



11.62 



8.22 



.40 





32 



102 



10.00 



11.92 



8.30 



.39 





[ 30 



130 



9.75 



11.72 



8.74 



.39 



At picking. 



2 Removal from 32° F. 



