Effect of the frequency of the mixing of coffee cherries put out for drying on the kinetics of drying and the relationship to ochratoxin A production

The effect of the frequency of the mixing of coffee cherries put out for sun drying on the kinetics of the drying, fungal growth and kinetics of ochratoxin A production was evaluated. The results showed that the more coffee cherries were mixed, the quicker they dried. This rapidity of drying led to a reduction of fungal development. Indeed, coffee cherries mixed eight and ten times a day, dried quickly and were free inside of fungi. However, infection by fungi gives little indication of ochratoxin A production in coffee cherries. Indeed, although coffee cherries mixed twice a day were more contaminated by fungi, the analysis of ochratoxin A content showed they were free of this mycotoxin. The coffee cherries that were more contaminated by ochratoxin A were those mixed four times a day (containing 0.35-5.46 microg kg(-1) ochratoxin A). Ochratoxin A contamination was essentially due to the presence of Aspergillus species capable of producing ochratoxin A inside the coffee cherries.