406 



ENCYCLOPEDIA OF PRACTICAL HORTICl'LTrRE 



only heated up to 149° F. (65° C.) in 

 the hot water and then removed would 

 surely spoil. These cans remained sound, 

 however, and thus the period of heating 

 indicated as sufficient for canning is un- 

 expectedly short. When the cans were 

 removed, they were cooled over night and 

 allowed to stand in the same room as 

 that in which the bottles were held. Ow- 

 ing to the large bulk of juice in the 

 cans of the size employed (1 gallon), it 

 is evident that the juice was maintained 

 at a sterilizing temperature longer than it 

 bottles or small-sized cans had been used. 

 This fact must be kept in mind if the 

 results here obtained are applied to other 

 sizes than gallon cans. 



The Carbonatiou of tlie Juice 



In addition to experimental work on 

 clarifying and on heating the juice, in- 

 vestigations were made on carbonating it 

 with a view to disguising the slight cook- 

 ed taste which it is impossible entirely 

 to avoid. Carbonating also increases the 

 palatability of the juice in the opinion 

 of many persons. The method used con- 

 sisted in carbonating the juice under 

 slight pressure and then heating in bot- 

 tles or cans, and no difficulty was en- 

 countered. In the simple experiments de- 

 vised and carried on in connection with 

 this work, the carbon dioxid (carbonic- 

 acid gas) was secured from a firm hand- 

 ling soda-water supplies. It was obtained 

 in liquid form in a steel cylinder furnish- 

 ed with a reduction valve and a gauge 

 and delivery tube, so as to deliver at pres- 

 sures up to 30 pounds. After clarification, 

 the juice was carbonated by pouring it 

 into a clean keg and running in the gas 

 up to a pressure of 15 pounds. 



The keg was provided with a thick 

 pine bung, through the middle of which 

 was bored a half-inch hole, which received 

 the rubber delivery tube from the cy- 

 linder of compressed gas. The bung was 

 soaked in water for a few minutes be- 

 fore use, so that it could be driven in 

 to make a tight joint, and was so fitted 

 that it projected beyond the surface of 

 the keg and could be readily loosened 

 when carbonation was finished. About 



12 gallons of juice were poured into the 

 keg. Carbon dioxid was admitted before 

 driving the bung in airtight in order 

 to expel the air which fills the space in 

 the keg not occupied by the juice. The 

 bung was then driven in by tapping with 

 a hammer and more gas admitted. The 

 keg was vigorously rocked so as to thor- 

 oughly agitate the juice and so accelerate 

 the absorption of the gas. 



The gauge was watched, and in these 

 experiments the pressure was not allowed 

 to go beyond 1.5 pounds per square inch. 

 The juice used in the carbonating work 

 was quite cool, ranging from 48° to 68° 

 F. (9° to 20° C.) in the different experi- 

 ments. As the carbonating of liquids is 

 apparently well understood, no attempts 

 were made to correlate the pressure, tem- 

 perature, and amount of gas which could 

 be dissolved in the juice. In these ex- 

 periments the juice was carbonated at a 

 pressure not exceeding 15 pounds until a 

 sample was drawn tasting distinctly of 

 the gas, this being the amount of car- 

 bonation desired. Working under these 

 conditions in the different trials, from 

 fifteen minutes to one-half hour was re- 

 quired to carbonate 12 gallons of juice. 

 The stream of gas was then stopped, the 

 bung cautiously loosened, the contents 

 of the keg poured out, and the juice bot- 

 tled or canned. 



The gas remains for some time in the 

 juice when under atmospheric pressure 

 and only gradually diminishes in quan- 

 tity, so that great haste in sealing the 

 juice is not necessary. If the carbonated 

 juice is to be sterilized in cans they 

 must be heated in stout frames to pre- 

 vent distortion of the can while hot and 

 consequent bursting. The finished canned 

 product bulges the ends of the cans to 

 some extent, but not enough to cause 

 permanent bending. The juice must not 

 be too highly charged with the gas nor 

 removed from the frames while still hot. 

 or such bending, with consequent weak- 

 ening of the soldered joints and bursting 

 of the can, may occur. 



The Best Containers for Sterilizing' Juice 



In the work with juice treated as above 

 (Ipscril)ed. bottles and cans have been 



