beneficial atmosphere of 5 percent carbon dioxide and 15 percent oxygen. 
Murata, Tsai, and Ogata (52) reported that sealing Jonathan apples in polyeth- 
ylene at room temperature preserved fruit quality as well as cold storage with- 
out sealing. Certainly length of storage would be critical when’ warmer than 
optimum storage temperatures are employed. 
Film Liners to Provide Modified Atmospheres 
Sealed film liners can provide modified atmospheres beneficial in ex- 
tending storage life. However, as Smock and Blanpied (70) have shown, use of 
a controlled-stmosphere storage room was safer than use of sealed polyethylene 
liners. It appears that there are too many hazards for wide commercial use of 
sealed liners, Sealed polyethylene liners are used by some commercial growers, 
but the possibility of getting unsuitable film in which the oxygen level may 
drop too low and injure fruit always exists. There is insufficient control of 
the atmosphere within liners (28, 70, 73). With improvements in uniformity of 
films, some expansion of box liner use for apple storage is likely. Development 
of. chemical inserts to control the atmosphere should be helpful (12, 21, 26). 
Workman (78, 80) listed the main advantages of using sealed differen- 
tially permeable films to provide modified atmosphere: 1) No attention is re- 
quired after packaging, 2) fruit can be removed from storage at any time, and 
3) no large capital investment is required. Workman (81) compared CA storage 
and sealed polyethylene liners for Turley apples over three seasons, Sealed 
liners helped maintain quality but sometimes increased scald over that in CA, 
Stop-Scald treatment was beneficial in controlling scald in liners. McGlasson 
and Jacobsen (48) stored Jonathan apples 7 months in sealed 1.5-mil polyethylene 
liners and found the fruit kept almost as good as in a controlled-atmosphere 
storage. After 8-1/2 months, apples in controlled atmosphere were in a much 
better condition than those in film, Hansen (22) reported that Golden Delicious 
could be kept in good condition until March in polyethylene liners. Controlled 
atmosphere storage extended storage life of this variety to April and May. Un- 
published tests by Hardenburg have shown that apples packed in sealed polyeth- 
ylene liners should not be stored in a controlled atmosphere room. Both Red 
and Golden Delicious suffocated under such conditions. 
Careful use of film liners can provide extended storage, intermediate 
between that in regular cold storage and that in a controlled-atmosphere stor- 
age. Leblond (38) stated that favorable gas concentrations can be obtained by 
wise selection of film, 
Eaves (14) made successful shipments of apples from Nova Scotia to 
Trinidad using l-mil Mylar liners in bulk bins (360 pounds). The liners were 
not sealed until after the fruit had been precooled. A 1.2 kg. (2.64 pound) 
perforated Mylar bag of lime was inserted under the fruit to absorb carbon 
dioxide, 
In addition to box liners, pallet covers, and bin liners, some research- 
ers have enclosed much larger volumes of apples in plastic film (1l, 13, 35, 
38). Eaves (13) in Nova Scotia has successfully tested economical 500- and 
1,000-box storages with l-mil Mylar polyester walls. A framework of 2" x 2" 
boards used with building paper supported the film, which was unrolled after 
precooling the fruit. Film was also spread on the floor and protected with 
building paper before loading with apples. After loading, all film joints were 
sealed with polyethylene tape. Accumulated carbon dioxide was removed by a hy- 
drated lime scrubber. Eaves reported that McIntosh, Red Delicious, and Northern 
57 
