APPLE JUICE EXTRACTION FOR JELLY 219 



Equipment 



Willi tlie exception of Red Astraciiaii, Rod Siberian Crab and Wealtliy 

 varieties, uniform Grade C apples kept in cold storage for from one to tliree 

 and one-half months were used. Just enough of the fruit was lirougiit to 

 tlie laboratory each morning for one day's run. Only sound, firm fruit was 

 used. A hand slicing machine adjusted to give slices one-eighth inch in 

 thickness, and a large sized food chopper equipped with medium knives were 

 used to slice or chop the fruit as desired. Pieces not over one-fourth inch 

 in diameter were obtained by the use of the food chopper. Tiie ciiopped 

 apples were somewhat finer in texture than the press stock usually obtained 

 liy the average shredder or mill in a cider factory. 



Unciilorinated Amherst tap water (pH 6.9) was used for the extractions. 

 Aluminum stew pans with close-fitting covers were found to be convenient 

 utensils in which to cook the apples with water. Circular gas burners were 

 used as the source of heat except where temperatures al)ove 100°C. were 

 desired. In tiie latter case steam-heated retorts or autoclaves were used. 



Extraction Methods 



Three pounds (L36 kilograms) of either sliced or ciiopped fruit were 

 placed in the covered aluminum pans, together with the required weight of 

 cold water. The gas flame was turned on fully until the desired temj)erature 

 was reached. It was then adjusted so as to maintain this temperature for 

 the period of the extraction. Where the ratio of fruit to water was high, 

 as in the 3:2 ratio, the pan contents were stirred with an aluminum spoon 

 when necessary to prevent scorching; otherwise no stirring was done. 



Upon completion of the extraction period, the contents were poured into 

 a moist cheese cloth (2 thicknesses), allowed to drain one minute, then well 

 squeezed by wringing both ends of the cloth in the hands for another minute, 

 after which the pulp was returned to the original stew pan, the desired 

 quantity of cold water added, and again extracted over the gas flame. 

 Similarly, a third extraction of the pulp was obtained. Thus for each apple 

 sample there was secured and kept separately, first, second and third ex- 

 tracts, as well as the pulp remaining after separation from the third ex- 

 tract. These various extracts and pulps were at once carefully weighed, 

 placed in glass fruit jars and pasteurized for 30 minutes at 71°C. (160°F.) 

 in case they could not be examined unmediately. Both chemical and organ- 

 oleptic examinations were made. Wiicn tartaric acid was used to acidify 

 the fruit, the desired amount in solution was added in the extraction water. 

 None was added except in the first extraction. For the sake of uniformity 

 the same quantity of water was added to the pulps remaining after the first 

 or second extractions, as was originally added to the apples. The several 

 juice extracts as well as the pulp were reserved for chemical examination and 

 for use in preparing the jelly samples. 



Method of Preparing Jelly 



For the sake of uniformity a given weight of juice, 511 grams (18 ounces), 

 was taken from each extract for conversion into jelly. When it was desired 

 to make a jelly representing the combined first and second extracts, amounts 

 proportional to the yield of each were taken so that the total weight was 511 

 grams. To this was added enough sugar to total 341 grams (12 ounces), 



