VEGETABLE AND FRUIT DEHYDRATION 



127 



ice, dry ice changes directly into a gas when it is heated. It is shipped 

 in 50-pound blocks, packed in quadruple corrugated cartons. Losses 

 in shipment and storage are approximately 10 to 6 percent per day, 

 respectively. Suitable storage bins can be made with hardwood 

 frames, sheet metal, or plywood walls for the lining, 6-inch layers of 

 cork or other insulation on the bottom and sides, and a 4-inch -thick 

 kapok, duck-covered pad as the cover. 



One-fourth pound of ground dry ice is placed in the bottom of a 

 5-gallon can and distributed uniformly. Then the vegetable is 



Figure 62. — Replacing air with carbon dioxide in a can of dehydrated carrots. 

 Operator is placing a 5-gallon can in a vertical-type evacuating and gassing- 

 chamber at left. Sealing machine is at right. 



weighed into the can, which is placed in a water trough equipped 

 with a conveyor, and the lid is placed on the opening in the can. At 

 once an evolution of carbon dioxide takes place and the air, and later 

 the gas, escapes around the lid. Two cubic feet of gas is formed in 

 the sublimation of the dry ice. After 6 to 12 minutes in water all the 

 solid carbon dioxide will have gasified and the can is capped after a 

 short period of standing in the air. 



The atmosphere in 5-gallon cans of cabbage or carrots has repeatedly 

 been brought to 0.8 to 1.0 percent oxygen by this method. Care must be 

 taken to avoid the sealing of cans in which ungasified dry ice is present ; 

 dry ice in a sealed can will cause cans to bulge later. The ordinary 

 precautions for handling dry ice should be observed. 



