d. Brown Rot. The brown rot of fruits has unsunken, decayed areas turning
dark brown to black in the center. The mold spore masses are yellowish gray. The skin
clings tightly to the center of the old lesion.
e. Anthracnose. Anthracnose is a defect with scattered black or dark brown
sunken spots covering firm decayed tissue. With moist conditions, there are pink spore
masses on the spots. Tomatoes are especially susceptible to this defect.
f. Fungal Rot and Gray Mold Rot. The loss of berries occurs with
dehydration, discoloration, and overripe, mushy, damaged, moldy, or spoiled fruit.
Common deteriorative conditions are fungal rot and gray mold rot. Berries are spoiled
primarily by Botrytis and Mucor.
g. Fermentation Defect. The species of several genera of yeasts
(Saccharomyces, Pichia, Torulopsis, and/or Candida) can cause a fermentation defect
in fruits.
h. Summary. A summary of microbial conditions of fruits is found in figure 5-1.
FRUIT
CONDITION
Apples
Fermentation
Apricots
Gray mold rot
Bananas
Storage rot, Black rot, Crown rot
Berries
Fungal rot, Gray mold rot
Citrus fruit
Soft rot, Black rot
Fresh fruit, in general
Blue mold rot, Black mold rot, Souring, bitter flavor, Soft rot
Peaches
Brown rot
Muskmelons
Alternaria rot, Bacterial spot, Bacterial soft rot, Blue mold rot
Blossom end rot, Bacterial spot, Late blight rot, Anthracnose,
Tomatoes
Soil rot, Sour rot
Watermelons
Anthracnose, Black rot, Stem-end rot
Figure 5-1. Microbial conditions of fruits.
MD0723
5-3