- 3 



As the freezing temperature was lowered from Freezing Point 1 

 to Freezing Point 2, no additional injury occurred until Freezing 

 Point 2 was reached. What causes the second freezing point to oc- 

 cur is not known, but apparently additional water suddenly becomes 

 available for freezing. Ice formation gives off heat so that the 

 temperature of the fruit remains about the same for a considerable 

 length of time (Figure 1). As soon as Freezing Point 2 was reached, 

 condition of the apples was affected in that they softened some 

 more. Nevertheless, the apples did survive the freezing with no 

 visual injury other than "contact points" when thawed. 



temp 



i n d i 



temp 



but 



appa 



grea 



soft 



i cal 



surf 



peel 



inju 



but 



crea 



fied 



The c 

 eratur 

 cated 

 eratur 

 whenev 

 rently 

 tly an 

 eni ng 



f reez 

 ace br 

 ; brow 

 ry , a 

 only s 

 sed, e 

 , the 



r i t i c 

 e dro 

 that 

 e at 

 er th 

 , dea 

 d the 

 the a 

 i n g i 

 n z i n 

 ning 

 dark 

 light 

 i t h e r 

 fruit 



al po 

 pped 

 at th 

 whi ch 

 i s te 

 th) 

 i r re 

 ppl es 

 njury 

 g and 

 of va 

 brown 

 ly di 

 at r 

 coll 



int d 



sharp 



is po 



this 



mpera 



ccurr 



spi ra 



qui c 



symp 



brow 



scul a 



ring 



scol 



oom t 



apsed 



un ng 

 ly fro 

 int th 



occur 

 ture d 

 ed in 

 t i n d 

 kly be 

 toms . 

 ning o 

 r stra 



near 

 red f 1 

 empera 

 , and 



f reezi ng 

 m F reezi 

 e apples 

 red v a r i 

 rop occu 

 the appl 

 ropped s 

 gan to d 

 These a 

 f the fl 

 n d s in t 

 the peel 

 esh. As 

 ture or 

 decay ap 



of an 

 ng Poin 



were k 

 e d with 

 rred, m 

 e . The 

 harply . 

 i scol or 

 re : va 

 esh , es 

 he fles 



underl 



time a 

 at 32°F 

 peared . 



apple 

 t 2. 

 illed. 



i n d i V 

 a s s i v e 



apple 

 Furt 



and t 

 ri abl e 

 peci al 

 h ; and 

 ain by 

 fter t 



brown 



was w 



Our d 



The 



i d u a 1 



dama 

 s sof 

 hermo 

 pro 



amou 

 ly ne 



wi th 



wate 

 hawi n 

 ing i 



hen the 



ata all 

 exact 

 appl es , 



ge (and 



tened 



re, upon 



duce typ- 



nts of 



ar the 

 severe 



r-soaked 



g in- 



ntensi - 



When apoles that had been frozen were sto 

 months at 32 , they looked the same as apples 

 frozen unless they had been frozen to the "kil 

 end of the storage period, those not killed we 

 from the controls except that they were always 

 softer depended on whether they had been froze 

 1 or to Freezing Point 2. Those frozen to Fre 

 softer than those frozen only to Freezing Poin 



red for up to 3 

 that had not been 

 ling point. " At the 

 re indistinguishable 



softer. How much 

 n to Freezing Point 

 ezing Point 2 were 

 t 1. 



We concluded from these tests that: 



1. Any freezing probably softens apples. 



2. Freezing to a fruit temperature of 26-28 F will probably 

 cause less softening than if the fruit temperature drops 

 to 22-24°F. 



3. Unless the apples were frozen to the killing point, sub- 

 sequent storage for relatively short times did not inten- 

 sify freezing injury. 



Rates of freezing and thawing within ranges that might 



occur in the field or in the storage had no effect on re- 



suits. The important question was how cold the apples 

 had become. 



