TEMPERATURE CHANGES IX CANNING FRUITS AND VEGETABLES. 13 



fell to 100° C. as rapidly as the temperature of the retort Avas low- 

 ered. The temperature at the ceuter of the glass container was thus 



130 



lao 



/lO 



/oo 



^?° 

 Sao 



I _:^=^:^ 



20 .30 'hO SO 60 



ao so /oo no 



T/M£ /N MWUTES 



ISO I30 /*0 ISO 160 170 ISO I90 £00 



Fig. 5. — Time-temperature relations for distilled water 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 ropresouting the rise in tcmperafuro during processing and the fall in tempera- 

 ture during cooling in water were plotted from readings made at intervals of 30 sec- 

 onds ; curves representing 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. ; C, at 116° C. ; 

 D, at 121° C. Fall when cooled : a'. From 100° C. in water at 16° C. ; I)', from 109° C. 

 in water at 17° C. ; c', from 110° C. in water at 15° C. ; d' , from 121° C. in water at 

 17° C. ; a, from 100° C. in air at 16° C. ; h, from 109° C. in air at 25° C. ; c, from 116° 

 C. in air at 25° C. ; d, from 121° O. in air at 25° C. 



/30 

















































— 









































^ 











































/^ 







































O 



\ 







































^ 70 





^ 



\ 







































— 













































^ 

































.30 















"^ 



^^ 



^ 















































^..^ 



















l_ 









































20 













20 JO 'M SO 60 



KX) 110 /SO 130 /-fO 



TiM£ //v Miwjres 



/SO I60 /70 /60 /f>0 SOO 



Fig. 0. — Tlme-temperalure relations for distilled water when processed in pint glass Jars 

 at 100°, 109°, 11(>°, and 121° C. and also when cuoled in air. The curves representing 

 the rise in temperature during processinj^ were plotted from rt^adings made at intervals 

 of 30 seconds; the curve representing cooling in air, from readings at internals of 

 5 to ir> minutes. Rise in temperature wlien processed: A. At 100° C. ; «, at 109° C. ; 

 C, at 116° C. ; D, at 121° C. a. Fall from 100° C. when cooled in air at 15° to 20° C. 



always at 100° C. when taken from the retort, and the coolinj; curve 

 from this starting point is all that is given. In the case of the tin 



