6 CIRCULAR 619, U. S. DEPARTMENT OF AGRICULTURE 



by some one of the numerous machines on the market. Some of the 

 machines consist essentially of rotating knives or cutting surfaces 

 operated by hand or by power. In others the cutting surfaces are 

 stationary, and the product is forced against the blades. Special 

 machines for cutting beans are made. In the most satisfactory type 

 of cubing machine the slices are cut, carried to a die, and forced 

 through by a plunger. 



Pitting and Seeding 



Manufacturers find it desirable to pit or seed stone fruits, as pitted 

 or seeded fruits dry more rapidly and sell more readily than those 

 from which the pits or seeds are not removed. Machines for pitting, 

 seeding, and paring most fruits are for sale by food-machinery manu- 

 facturers, but the greater part of dried fruits are pitted by hand. 



Traying 



After the raw material is prepared in the desired form, no time 

 should elapse before traying and subsequent treatments preliminary 

 to its being placed in the drier. No definite rule can be given for 

 determining the quantity of material to be placed on a unit area of 

 tray surface. Experience will soon show the operators how much will 

 insure even, rapid drying. Many of the larger fruits must be trayed 

 only one layer deep. Overloading trays must be avoided. 



Trays should be light but capable of withstanding strain, and they 

 should permit a maximum exposure of the materials. Trays of the 

 type most often seen have a spreading surface formed either of wire 

 screen Or wooden slats held firmly in a narrow but rigid wooden or 

 metal frame. Many of the trays now in use have been employed in 

 sun or other drying. If new trays are made, the one-man tray, about 

 2% to 3 feet square, will be found to be the most convenient. 



Wooden-slat trays can be more cheaply constructed than wire- 

 screen trays, but they have a high rate of upkeep. These trays, how- 

 ever, are not affected by sulfur fumes or fruit acids, for which reason 

 they are preferred for most fruits. 



Conveying the Trayed Material 



The trucks for conveying loaded trays are of two general types. 

 In one a skeleton frame is provided with cleats, upon which the 

 trays rest. The cleats are from 2 to 4 inches from center to center 

 above one another. These trucks are made of various combinations 

 of wood or angle iron. The other, which may be called the stack 

 type, has a low floor supported by wheels 3 to 5 inches in diameter. 

 The trays are piled or stacked one above the other, and the desired 

 space between them is maintained by the raised sides of the trays. 

 Various alterations may be made for convenience in handling and 

 loading. 



PRETREATMENT 



The original method of preparing fruits and vegetables for drying 

 consisted in washing, peeling when desirable, cutting, and traying. 

 By this method most dark-colored materials made fairly presentable 



