TEMPERATUKE CHANGES IN CANNING EKUITS AND VEGETABLES. 



19 



approaches that of the retort or bath. It requires about '^0 minutes 

 for the pint glass jar and about 3.5 minutes for the quart jar to reach 



/30 

 ISO 

 110 

 100 





 %70 





so 30 ■VC 



SO 60 70 eo 



Fig. 12. — Time-tempergtui-e relations for string beans in 2 per cent brine when processed 

 in No. 3 tin cans at 100°, 109°, 116°, and 121° C. and also when cooled in water and 

 in air. The curves representing the rise in temperature during processing and the 

 fall in temperature during cooling in water were plotted from readings made at in- 

 tervals of 1 minute and 1 minute ; those represeatiiiy: fall in temperaiure during 

 cooling in air. from readings at intervals of 5 to 10 minutes. Rise in temperature 

 when processed : A, At 100° C. ; B, at 109° C. ; G, at 116° C. ; D, at 121° C. Fall in 

 temperature when cooled : a' , From 100° in water at 17° C. ; 6', from 109° in water 

 at 1GJ° C. ; c', from 116° in water at 16J° C. ; d' , from 121° in water at 16*° C. ; 

 a, from 100° in air at 25|° C. ; 6, from 109° in air at 2.51° C. ; e, from 116° in air at 

 25J° C. ; d, from 121° in air at 22° to 26° C. 



/eo 

 //o 

 /oo 

 so 



f 



r 





eo \3<j ^o eo eo 



tao no /so /eo /to tao /go soo 



Fig. 13. — Time-temperature relations for string beans In 2 per cent brine wher, processed 

 in pint glass jars at 100°, 109°. 116°, and 121° C. and also when cooled in air. The 

 curves representing the rise in temperature during processing were plotted from read 

 ings made at intervals of 1 minute ; the curve represcjiting the cooling in air, from 

 readings at intervals rtf 1 to "> minuies. Rise in temperature when processed : 

 A, At 100° C; B, at 109° C. ; C, at lU! C. ; D, at 121° C. a. Fall in temperature 

 from 100° when cooled in air at 18° to 22° C. 



the same temperature. It is evident that so far as time-temperature 

 relations in the can are concerned there need be little iliti'erence in 



