Fungus / Mold Damage


Washed Process Mold / Fungus

Washed Process Mold

Dry Process Mold

Dry Process Mold

Español: Daño por hongos
Français: Fève avariée sèche

Fungus or Mold Damage are Primary (Category 1) defects: 1 affected bean = 1 full defect
Fungus damaged washed processed beans are recognized by white to yellow or gray “powdery” spots (spores) in early stages of the attack, which grow in size until covering the entire bean. Fungus damaged dry processed beans show a moldy pattern on the whole bean surface. Fungus damaged beans release spores that may contaminate other beans.
Cup:May produce moldy, earthy, dirty, over-fermented and phenolic tastes
Consideration:Ochratoxin A (OTA) risk
Cause(s):AGRICULTURAL & PROCESSING: Fungus damaged beans are commonly caused by fungi from the Aspergillus, Penecillium, and Fusarium genus, which can infect beans at any point from the field, harvesting, processing and storage, particularly where high environment temperatures and relative humidity induce fungus growth and/or bean moisture is excessive. Fungi growth is likely if substantial fungus spores are present and beans posses a high rate of water activity.
RemediesAGRICULTURAL: Since coffee is grown in tropical humid regions that favor fungal growth, effort must be made to limit the sources from which the fungus spores originate. Avoid picking cherries from the ground, excessive broca (CBB)-damaged beans and unused beans, skins and/or pulp juices in harvesting bags or containers.
PROCESSING: Infection can be prevented by implementing best practices at dry and wet processing facilities. Causes of infection include: cut or chipped beans during the pulping process, uncontrolled fermentation, beans lodged or otherwise left in pulpers, fermentation tanks, pipes or any other part of the washing station, delay or interruptions during the drying process, severely broca (CBB)-damaged beans and storing coffee in cherry or parchment under conditions of high humidity and temperature.Fungus damaged beans can be recognized in coffee cherries and parchment from their powdery dark or whitish spots, as well as a soil aroma but are more visible when husked in the dry mill.When husked, color sorters can remove the most critically fungus-damaged coffee but slightly fungus damaged beans can only be removed through hand sorting.