Grading of Fermented and Dried Cocoa Beans Using Fungal Contamination, Ergosterol Index and Ochratoxin a Production

Sixty four samples of cocoa beans replicated in quadruplicates were collected from five warehouses from southwest Nigeria and examined for fungal loads, ergosterol and eohratoxin A The levels of all the variables obtained were further used as indices for cocoa grading into food quality, FoQ (erg less than 5 mg/kg; OTA less than 1 ㎍/kg), feed quality, FeQ (erg = 5~10 mg/kg; OTA in the range of 1.1~3.11 ㎍/kg), Screen for mycotoxin, SFM (erg = 10~20 mg/kg; OTA from 3.12 ㎍/kg and above) with fuel quality, FuQ having erg greater than 20 mg/kg and OTA greater than 6.12 ㎍/kg. Using these ergosterol indices, 18.75% of the cocoa beans examined was classified with the FoQ, 18.75% with the FuQ while 31.25% was classified with both the FeQ and the SFM, respectively. In conclusion, ergosterol can be used as a rapid index to grade fermented, dried cocoa beans meant for export.