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

Abstract

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.

Challenges in Specialty Coffee Processing and Quality Assurance

“…Coffee cherry drying, was identified as one of the steps during which ochratoxin A (OTA) formation can take place, particularly under humid tropical conditions. In particular, in coffee, ochratoxigenic fungi may develop on ripe and unripe cherries [57], on beans, during fermentation [58][59][60][61][62][63][64][65][66][67][68][69][70], during storage, packaging and during roasting and brewing [71][72][73][74].…”

“…The use of patios with earth floors should be avoided to produce the highest quality coffee [62,67,68]. Wet processing is applied to Arabica coffee beans and the mycobiota was highly influenced by (a) fermentation (water quality and equipment used) and (b) drying (time period, cleanliness of equipment and environment).…”

Ochratoxin A decontamination: A review

“…In the case of tropical crops, it is imperative not to store fresh products (FAO, 2006;Goryacheva et al, 2006;Teixeira, Taniwaki, Pitt, Iamanaka, & Martins, 2001). Piles have to be turned over in order to promote their aeration and to prevent ochratoxigenic mold development (Kouadio, Agbo, Lebrihi, Mathieu, & Dosso, 2006). The FAO/WHO/UNEP (1999c) recommends carrying out a fast drying and, in general, under a moisture level of 10%.…”