Mechanical and Temperature Effects on Shelf Life Stability of Fruits and Vegetables - Food Shelf Life Stability: Chemical, Biochemical, and Microbiological Changes - page 66

I NTERMITTENT W ARMING
Interruption of cold storage with warm periods has been shown to be beneficial in
extending the storage life of apples, citrus, cranberries, cucumbers, nectarines, and
many other fruits by minimizing chilling injury. 113 Wang and Baker 129 found that
intermittent warming increased the proportion of unsaturated polar lipids in peaches,
cucumbers, and sweet peppers, and lessened the deterioration of these products at
low temperatures. Peaches, when warmed intermittently, were found to have reduced
incidence of wooliness 171 due to the production of adequate levels of pectolytic
enzymes, pectinesterase, and polygalacturonase. Tomatoes have also responded
favorably to rewarming at 18°C as shown by the recovery of ultrastructural changes
in the mitochondria and plastids. 131
C HEMICAL A PPLICATION
Application of fungicides, antioxidants, and growth regulators have been found
suitable for reducing chilling injury of some commodities. Valencia oranges often
incur chilling injury during long-term storage. Wild and Hood 120 reported that dip-
ping Valencia oranges in a water suspension of the fungicide thiabendazole (TBZ)
at 1000 mg/L and a temperature of 53°C for 2 min reduced chilling injury when
fruits were subsequently stored at 1°C for 15 weeks. Inducing mechanical injury to
the rind will slightly increase the incidence of chilling injury during long-term
storage. TBZ had been reported to significantly reduce surface pitting in grapefruits
during prolonged storage at 8°C. 172 McDonald and co-workers 115 compared the
effectiveness of TBZ and imazalil dips at 53°C for controlling decay and reducing
susceptibility to chilling injury of “Marsh” and “Redblush” grapefruit. Dipping at
53°C with fungicide generally reduced the susceptibility of grapefruit to chilling
injury. Imazalil was found to be more effective in reducing chilling injury suscep-
tibility and controlling decay than TBZ. 115 Scald in lime could be reduced by 12 to
50% using diphenyl treatment. 117 Gibberellic acid dips or injection of apples was
shown to reduce low-temperature breakdown. 111 Antioxidants like diphenylamine
and ethoxyquinn are widely used to control superficial scald in apples. 106
H YPOBARIC S TORAGE
Hypobaric storage is the storage of the produce under reduced atmospheric pressure.
Few fruits are suited for hypobaric storage. Pantastico and co-workers 168 have shown
that when Lacatan bananas were held at 5°C and 220 mm Hg pressure, symptoms
of chilling injury were reduced and the green color was retained for approximately
1 month. At 220 mm Hg pressure and temperature of 4.5°C, limes did not develop
symptoms of chilling injury for 4 weeks in storage, while “Marsh” grapefruit showed
only slight symptoms of approximately 4.4% after 7 weeks in storage. 117
R ECOMMENDED R EFRIGERATED S TORAGE C ONDITIONS
Fruits and vegetables should be stored above the critical temperatures at which they
show symptoms of chilling injury. Once a produce exhibits chilling injury symptoms,