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TECHNICAL BUI>LETIN 1^ 



rigure 1. Bloom Gelometer Used to Make Jelly Strength Tests. 



The instrument is electrically manipulated and allows fine shot to flow 

 into the pan above the plunger until the latter has penetrated into the 

 jelly a definite depth, usually 5 nini., when the circuit is closed and the 

 flow stopped. The jelly strength is merely the weight in grams of the shot 

 on the pan. Straight sided jelly tumblers containing .56 grams (2 ounces) 

 of jelly, were used in the tests, all of which were conducted at room tem- 

 perature, 20° to 23°C. (68° to 74° F.). The flow of shot was always regu- 

 lated so that a definite weight flowed through the outlet in a given time — in 

 other words, the orifice was opened exactly the same distance (regulated 

 on the instrument) for each test. For details regarding the use of the 

 Bloom gelometer for jelly strength determinations in fruit and pectin jellies 

 the paper by Fellers and Griffiths (6) should be consulted. 



CHEMICAL COMPOSITION OF THE APPLE VARIETIES 

 USED FOR JUICE EXTRACTION 



Before extracting the juice by heat, representative samples of each variety 

 were subjected to chemical examination. In most cases several analyses of 



