Necessities.
—In the order of progress the first necessity for refrigeration is the use of ice for chilling water for fats and meats. Practically every packing house is now equipped with a small ice making plant both for its use, and with commercial possibilities of selling ice.
Ice Plants.
—Ice plants are of various kinds:
- (1) Common ice made from filtered water without processing.
- (2) Raw water ice made from filtered or treated water, aerated or agitated, while freezing.
- (3) Distilled water ice made from condensed steam, reboiled.
- (4) Plate ice, made from raw water in large plates and cut up into blocks of convenient size.
In the production of distilled water there are various methods which will not be treated upon here.
For the icing of cars and for ordinary cooling purposes ice made by process No. 1 is amply good except, perhaps, if the water from which the ice is made should not be clear, it may be necessary to use a portion of the bottom of the cake for car icing purposes only.
Natural Ice.
—The situation and climate has much to do with the determination as to whether the packer can afford to harvest natural ice for general use. For example, if the plant be situated in a northern climate alongside a suitable stream adjacent to the plant, the harvesting of ice and its storage can be afforded. However, if the ice is stored at a remote point and teaming or car shipment of ice is necessary, then the manufacturing plant will probably be the more economical.