32 



CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE 



Because apples are not a highly perishable fruit, like the peach or 

 strawberry, for example, and move during the cool seasons of the year, 

 many shippers order their cars shipped under ventilation. Under this 

 service no particular control of the temperature of the load is possible, 

 the vents being kept open at all times when the outside temperature is 

 above a stated minimum, usually 32° F., and are closed when the outside 

 temperature drops to this minimum. If the fruit is warm when it is 

 loaded, cooling in transit depends entirely on encountering colder out- 

 side temperatures. If the fruit is colder than the outside temperature, 



t : ' y iS^Wi(l2 l S, 



ml 







Figure 16. — Egg-crate type of fiberboard containers, which afford maximum 

 protection against bruising. The diversity of shapes required for different- 

 sized apples is a disadvantage. 



the load will warm up. This is particularly likely to occur with ship- 

 ments from cold storage. Such shipments should never be forwarded 

 under ventilation service. If transit refrigeration is not desired, 

 they should be billed "Plugs in. Vents closed to destination." Thus 

 the refrigeration stored up in the cold load can be utilized throughout 

 the trip. 



Movement under ventilation is the cheapest service available to the 

 shipper. From the standpoint of the condition of the fruit, the use 

 of ventilation is justified only with apples that are intended for im- 

 mediate use. With apples intended for storage at destination, ven- 

 tilation service jeopardizes their potential storage life because of the 

 rapidity with which the ripening process proceeds at warm tempera- 

 tures, as already pointed out (p. 8). Consequently, as a rule, apples 

 that move under ventilation are not worth as much as those that are 

 refrigerated in transit. This does not mean that ventilated ship- 

 ments necessarily sell for less than refrigerated consignments, but it 



