Principles of Jelly-Making 1253 



plan has much to commend it. Frequently time is precious in the fruit 

 season and if the juice extractions are properly heated to boiling, and 

 sealed in well-sterilized cans just as is canned fruit, they will keep quite 

 as well as the latter, and jelly can be made when desired. 



SEALING UP JELLIES 



If jellies are to stand any length of time before using they should be 

 properly sealed from the air. The glasses, having been filled completely 

 with the hot jellies, should be set in a cool place for the contents to harden. 

 It is well to cover jellies that are slightly undercooked with panes of glass 

 and harden them in the sun. In either case, when the jellies are well set 

 the glasses should be filled with hot paraffin (the jelly will have shrunken, 

 leaving space for this) — not merely melted paraffin, but hot, in order 

 that all germs which may have fallen on the surface of the jelly will be 

 killed and future trouble from them obviated. Close with hot, clean tin 

 covers and keep in a dry, cool place. 



A JELLY FAILURE 



A very interesting and instructive jelly failure was brought to the 

 writer's attention. This failure was a thin jelly full of transparent cubical 

 crystals. Examination proved these to be uninverted sugar, that is, the 

 original sugar used. Further examination showed that the original juice 

 had been but slightly acidic, and also that it was not rich in pectin. Ques- 

 tioning the maker disclosed the fact that the sugar had been added near 

 the end of the jelly-making process (short-boiling). Now, at least three 

 errors were evident: (i) an overproportion of sugar, (2) a weakly acidic 

 juice, and (3) one not rich in pectin. Consequently the jelly had never 

 " jelled "; a mere sirup had resulted, from which the uninverted sugar 

 had subsequently crystallized out. The total result was much the same 

 as though a thick sirup from sugar had been merely colored and flavored 

 by fruit juice and allowed to stand until crystallization of the sugar had 

 occurred. 



GENUINE ORANGE AND LEMON JELLIES 



The writer had frequently noticed that well-made orange marmalade 

 always showed a jelly-like appearance, denoting that there must be pectin 

 in the fruit. The alcohol test applied to the squeezed-out raw juice 

 showed its entire absence. Subsequent experiments finally located the 

 pectin in the white inner skin of the fruit. Similar examinations of the 

 lemon showed its presence there also in the white inner skin, but none in 

 the raw juice. After many experiments it was found that excellent 

 genuine orange or lemon jellies could be made by careful extraction of this 



