Dec. 1895.] 



EVAPORATION OF FRUIT. 



261 



he was firmly of opinion that the evaporator offered the best 

 solution of the problem how to prevent the loss which invariably 

 occurred in this country whenever an unusually good crop of 

 fruit was produced. 



There are several kinds of evaporating machines constructed 

 upon the same general principles, and differing merely in details. 

 These have been exhibited at the Shows of the Eoyal Agricul- 

 tural Society of England, and at other shows. Some are 

 German, others are American inventions. Some of the machines 

 are upright with long vertical cases ; others have long horizontal 

 cases or trunks, but they all contain a series of wire trays 

 arranged one above the other, upon which the fruit is placed. 



These machines have three parts, the stove or furnace, the hot 

 air chamber, and the fruit drying chamber. In the upright or 

 vertical machines, the stove or furnace is at the bottom, and has 

 doors arranged so as to regulate the draught. The heated air pass- 

 ing into the chamber is raised to a uniform temperature by means 

 of dampers, and is carried into the drying chamber in which the 

 trays with the fruit upon them are ranged one above another. 



In the horizontal machines the heated air passes from the hot 

 chamber in which the heat is generated into inclined or hori- 

 zontal distributing flues. There are two flues, one ascending, 

 the other descending. 



The trays upon which the fruit is laid for desiccation are made 

 of wood and wire-netting, and of various sizes and patterns. Two, 

 three, or four trays are put in at once, according to the description 

 of fruit to be dried. The machines may be worked out of 

 doors or in a building, though it is better that they should be 

 under cover. The smaller machines can be easily moved from 

 place to place, but care must be taken to place them in sheltered 

 spots and where the draughts for the distribution of the heat 

 may be properly regulated. Large machines must be in 

 buildings. It is convenient that the furnace should be set below 

 the basement, as this entails the lowering of the trunk or case, 

 thereby lightening and lessening the work connected with moving 

 the trays. There should be plank tables fixed near the machine 

 for putting the trays upon and for preparing the fruit. It is most 

 important that the ventilation of the building should be good so as 

 to carry off quickly the steam and reek. Oast-houses might pro- 

 babl}^ be utilised before and after hop picking for this purpose in 

 hop-growing counties. In fruit drying, as in hop drying, every- 

 thing depends upon the temperature and its equable and proper 

 maintenance and regular distribution. It varies between 180° to 

 220° Fahr. according to the kind of fruit and the kind of 

 machine, as will be shown later. If the heat is sufficient and is 

 equally maintained, certain chemical changes occur. The albumen 

 should be coagulated just as the white of an egg is when boiled, 

 and glucose or fruit-sugar is formed by the combination of, the 

 starch with the water from the fruit, and a slight skin is raised 

 over the fruit which preserves it. The fruit jelly, known .as 



