22 rNFKUMKSTED APPLE JUICE. 



organisms, such as the molds and acetic acid ferments which require 

 the presence of air for their development. The carbon dioxid pro- 

 duced by the action of the yeast on the sugar displaces the air above 

 the juice in the container, and the air originally present in the juice 

 is probably utilized by the yeast in its development so that such juice, 

 if properly handled, yields a sound, fermented apple juice or cider. 

 In the presence of preservatives, however, the yeasts are not per- 

 mitted to develop and exert their effect of excluding other organisms, 

 some of which will develop and produce bad flavors, rendering the 

 juice unpalatable if not totally unfit for consumption. Sterilization, 

 on the other hand, excludes the yeasts and the other organisms as 

 well, so that the original flavor of the product, aside from a slight 

 change due to heating, is maintained. 



SUMMARY. 



(1) The experiments described show conclusively that it is possible 

 to sterilize apple juice in wooden containers, the product remaining 

 sound for at least six months under actual observation. The precau- 

 tions which must be taken to insure this are as follows : First paraffin 

 the containers on the outside, then sterilize, and fill with juices heated 

 to between 149 and 158 F. (65 to 70 C.); seal, taking measures to 

 relieve the vacuum produced by the contraction of the juice on cooling 

 by filtering the air through cotton. Twenty-four 10-gallon kegs suc- 

 cessfully stood a severe shipping test, showing no loss due to fermen- 

 tation of the juice. The juice so prepared was found to be palatable, 

 and acceptable as a summer drink. 



(2) It is demonstrated that apple juice can be successfully sterilized 

 in tin containers, using the type of tin can sealed by the mechanical 

 process, excluding all metals from contact with the juice except the tin 

 of the can. Where lacquered cans are used the contamination with tin 

 was reduced about one-half. Apple juices were canned and sterilized 

 by heating in a hot water bath, up to the temperature of 149 F. (65 

 C.) for a half hour, and then were allowed to cool. These juices pos- 

 sessed only a slight cooked taste due to the heating and retained much 

 of their distinctive apple flavor. It was found that from finely fla- 

 vored apple juice a first-class sterile product could be made, while a 

 poorly flavored apple juice yielded an inferior product. The process 

 conditions mentioned were not quite thorough enough to sterilize all 

 of the varieties canned. A slight increase in the temperature or 

 time of processing, or both, should be made, the temperature not to 

 exceed 70 C. (158 F.) in any case. 



(3) The best treatment for sterilizing in glass was found to consist 

 in heating for one hour at 149F. or for one-half hour at 158F. Heat- 

 ing for one hour at 158 did not produce marked deterioration in flavor, 



