STORAGE 



means or by ice, cold storage can onU 

 be accomplished by luamtdimng a de 

 sired temperature over i long period 

 In order to secure thi« the crmpart 

 ments in which the products tit i-i^f 

 are to be held must be i i 1 1 th in 

 sulated from outside heat i j il I 



Successful experimental i 1 1 1 i 1 1 i 

 by mechanical means was i i j li 1 1 

 as early as the middle of the eiglitteutli 

 century, but no successful commercial 

 application of cold storage was made un 

 til after the invention of Lowe s car 

 bonic acid " machine in 18b7 although 

 the present growth of the indu try is 

 due to the invention of the ammonia 

 compression machine by Professor Carl 

 Linde in 1875. 



The process was first exteu ively ap 

 plied to the preservation of me it fa h 

 etc., but as early as 1881 the Mechanical 

 Refrigerating Company of Bo tonopene 1 

 a cold storage warehouse which m ii 1 

 the beginning of mechanical refri^ i 

 tion as applied to horticultural produ i 

 Other companies were then organ i/ i 

 until now there are about 1 200 refii.,t-i 

 ating plants in the L nited state t 

 which about 600 are use<l mc th fji 

 horticultural product ioreign emu 

 tries are now following the esanifle cf the Lnited 

 States, and London, Liverpool, Glasgow, Pans and 

 other European cities offer facilities for storing such 

 products. In the United States, Chicago is the great 

 center for fruit storage, single firms holding as niauy as 

 100,000 barrels a year. Apples are the principal storage 

 fruit, good winter sorts holding their form, color and 

 flavor better than any other commercial fruit when held 

 for long periods in cold storage. Another reason why 

 the apple is a favorite in cold storage is that people use 

 it continuously over a long period. A good apple is 

 always a relish. The apple, too, is the fruit which best 

 pays the producer to hold in cold storage. 



From the nature of the case, mechanical refrigeration 

 will usually be confined to transoceanic trade, and to 

 cities and towns where the principal business of the 



172<) 



2407. Structural details of the 



2406 Apple storehouse in Vermont 



refngeratmg machinery will be the production of ice 

 for commercial and domestic use, the cold storage 

 warehouse being a side issue to ice-making. The 

 fruit-grower who wishes to avail himself of the ad- 

 vantages of cold storage must either ship his product 

 to the city or depend upon natural ice to reduce the 

 temperature of his warehouse. If he is in a climate 

 where a supply of natural ice is available, his most 

 economical plan is to make provision to use it. If in 

 the far South he must own an ice plant or purchase 

 artificial ice. 



To successfully handle peaches and plums in car- 

 lots, one must nowadays have a supply of ice in order 

 to avail oneself of the best service of the Fruit-Growers' 

 Express or other lines The cars come iced, it is true, 

 but before starting them on their journey it is safest for 

 the grower to have a sufficient supply of ice to fill the 

 pockets of the car 



To hold apples from harvest time until the over- 

 supply of the season shall have been removed, requires 

 storage rooms artificially cooled to a temperature suflS- 

 ciently low to check the process of ripening, which is 

 in reality the conversion of the starch of the imma- 

 ture fruit into sugar. As long as the starch remains 

 as such, fermentation and decay cannot 

 act, but as soon as sufficient water and 

 heat are added to convert the starch 

 into sugar, ripening proceeds until fer- 

 mentation and decay complete the work. 

 The object of cold storage, then, is to 

 check the ripening process, or, if the 

 fruit is ripe, to maintain a temperature 

 sufficiently low to check fermentation. 

 Theoretically, then, green or immature 

 fruits will keep better than ripe ones. 

 Green fruits should keep as well at 36° 

 as a ripe fruit at 32°, and this is in ac- 

 cord with experience. 



To successfully hold fruit in cold stor- 

 age, three conditions are essential: (1) 

 a low temperature; (2) an even tempera- 

 ture, and (,'i) sufficient moisture to pre- 

 vent shrinkage, thus keeping the fruits 

 plump and crisp. Even in storage 

 rooms in which the humidity of the air 

 remains saturated, as indicated by the 

 ordinary wet- and dry-bulb thermome- 

 ter, considerable loss of moisture will 

 take place from fruits stored in crates or 

 open bins, while much less is lost by 

 those stored in tight receptacles. Indi- 

 vidual Baldwin apples under observation 

 in a room at 32° F.. from Januarv 4 to 



