UNITED STATES DEPARTMENT OF AGRICULTURE 



DEPARTMENT BULLETIN No. 1141 



Washington, D. C. 



May, 1923 



EVAPORATION OF FRUITS 



By 



JOSEPH S. CALDWELL, 



Plant Physiologist, Office of Horticultural and Pomological Investigations 



Bureau of Plant Industry 



CONTENTS 



Page 



Eilent and character of the fruit-drying industry .... 1 



Principles involved in drying fruits 4 



Community drying plants 7 



Buildings and equipmentfor drying 8 



The kiln evaporator 8 



The individual kiln 9 



. 15 



. 17 



. 24 



. 27 



. 35 



. 35 



. 35 



The kiln-drying plant 



The apple-drying workroom and its equipment 



The prune tunnel evaporator 



The operation of the tunnel evaporator . . 



Small driers or evaporators 



Treatment of the various fruits 



Apples 



Page 

 . 45 

 - 49 

 . 49 

 . 50 

 . 50 



Treatment of the various fruits — Continued 



Peaches 



Apricots 



Pears 



Cherries 



Prunes 



Smallfruits ' 54 



Storing the dried products 57 



Preparing evaporated fruits for market 58 



Packing evaporated apples 58 



Packing peaches, apricots, and pears 59 



Packing prunes 61 



Laws relating to evaporated and dried fruits 62 



WASHINGTON 

 GOVERNMENT PRINTING OFFICE 



1923 



