Agriculture Reference
In-Depth Information
Fig. 5.4.
Relationship between water loss and green-life of tropical fruits.
Careful handling is the most ef ective method of limiting injury. This
involves careful harvesting practices, placing fruit in buckets or boxes,
ensuring that the bags and buckets are clean and free of dirt and grit that can
abrade the skin.
Controlled and modi
fi
ed atmosphere storage
During respiration, the other substrate besides sugars is oxygen, while the
major product is carbon dioxide. Controlled and modifi ed atmosphere storage
methods normally reduce the oxygen levels to slow respiration and increase
carbon dioxide levels to slow conversion of substrates. Controlled atmosphere
(CA) storage is a more controlled, active regulation of oxygen and carbon
dioxide levels, while modifi ed atmosphere (MA) storage is more passive and
relies on gas exchange. Both CA and MA methods are supplements to good
temperature management and do not replace temperature management
(Kader, 1993; Yahia, 1998).
Generally oxygen levels are reduced to 3-4% (Table 5.5); below 3%,
frequently the fruit may become anaerobic and of -fl avours will develop and
alcohol production occurs. Carbon dioxide is increased to 4-10%, though
greater care is needed as of -odours and fl avours frequently develop. The
potential benefi ts of MA and CA for tropical crops depend on the type of
crop, pre- and postharvest handling methods and length of shipping period.
Frequently, exported tropical fruits have a number of additional postharvest
