c. Color Changes. The following external color changes are commonly
associated with mold growth: blue, green, red, white, black, pink, and brown. These
colors may be due to colonies of specific species of mold.
d. Texture. Microbial spoilage may cause the texture to become soft, mushy,
water-soaked, slimy, dry, or hard.
MECHANICAL DAMAGE OF FRESH FRUITS AND VEGETABLES
5-5.
a. General. Mechanical damage is due to the action of machinery, mishandling,
and/or improper packaging, and may result in cuts, punctures, bruises, and/or
abrasions. The fleshy fruits are very susceptible to mechanical damage. Product
texture may be soft around any cut, puncture, or abrasion. Both internal and external
examination of the product may be necessary to determine the extent of mechanical
damage.
b. Darkening in Color. The following color change may indicate mechanical
damage: a darkening in color of both external and internal tissues of the affected area.
c. Improper Physical Handling. Improper physical handling can result in
injuries caused by impact, compression, abrasion, puncturing, tearing, or two or more
such actions combined. Some FF&V items are more easily injured than others. Some
show objectionable symptoms more readily. However, none of the items are immune to
damage. Once damaged, the items lose value because they become discolored,
unsightly, and prone to invasion by decay organisms.
(1) Impact damage. Impact damage occurs when an item hits a surface
with sufficient force to damage or even separate its cell. The external sign is a bruise or
a crack.
(2) Compression. Compression also causes bruising and cracking.
Compression occurs primarily during or after packing as a result of forcing too much
product into too small a container. While vegetables and melons should be packed
firmly enough to avoid chafing, they should not be stuffed in so tightly that their curved
surfaces become flat. This happens all too often with lettuce.
(3)
Abrasion. Abrasions can occur:
(a) During harvest when roots or tubers are dug.
(b) When vegetables are conveyed at excessive speed.
(c)
During packing.
MD0723
5-6