AMERICAN FRUIT-EVAPORATORS AND EVAPORATING. 



535 



all fruit, and which is the primary cause of its decay, has been rendered 

 inoperative, and all germs of animal or vegetable life have been 

 destroyed by the high heat. It is by this chemical change which I 

 have brieliy described, in uniting a part of the water already contained 

 in the fruit with the fruit starch, that these truly evaporated products 

 are rendered more wholesome, more digestible, more indestructible, 

 and are thereby made more valuable, not only as articles of food, but 

 because they are not subject to deterioration and loss. And it is also 

 the reason why a bushel of apples will make more pounds of evaporated 

 fruit than can be made by sun-drying it, as a portion of the contained 

 water which would otherwise be lost is retained by combining with the 

 starch to form glucose, and the carbonic acid, which is always lost in 

 the slow decomposition resulting from sun-drying, is retained in its 



Fig. 36. 



natural combination with the other substances composing the fruit, 

 and hence it is heavier. These profitable and healthful chemical 

 changes which I have mentioned are all in accordance with the laws 

 of nature, and are certain to take place if the necessary conditions of 

 heat and air, as I have detailed them, are properly supplied ; otherwise 

 you will have a different product, and no matter how fine your apples, 

 how perfect your paring, coring, and trimming, or how white you may 

 have bleached them, you have not made truly evaporated fruit, and 

 no matter how many have been deceived by its bright colour, or full 

 weight, or fancy packing, your fruit will not stand the test of long 

 keeping in warm, damp weather. The natural starch, gluten, and 

 albumen of the fruit, instead of being cured, or made indestructible by 



