Ochratoxin A-producing Aspergilli in Vietnamese green coffee beans

Abstract

Aims: To determine the incidence and severity of infection by ochratoxin A (OA)‐producing fungi in Vietnamese green coffee beans. Methods and Results: Aspergillus carbonarius, A. niger and yellow Aspergilli (A. ochraceus and related species in section Circumdati) were isolated by direct plating of surface‐disinfected Robusta (65 samples) and Arabica (11 samples) coffee beans from southern and central Vietnam. Significantly, more Robusta than Arabica beans were infected by fungi. Aspergillus niger infected 89% of Robusta beans, whereas A. carbonarius and yellow Aspergilli each infected 12–14% of beans. OA was not produced by A. niger (98 isolates) or A. ochraceus (77 isolates), but was detected in 110 of 113 isolates of A. carbonarius, 10 isolates of A. westerdijkiae and one isolate of A. steynii. The maximum OA observed in samples severely infected with toxigenic species was 1·8 μg kg−1; however, no relationship between extent of infection and OA contamination was observed. Conclusions: Aspergillus niger is the dominant species infecting Vietnamese coffee beans, yet A. carbonarius is the likely source of OA contamination. Significance and Impact of Study: Vietnamese green coffee beans were more severely infected with fungi than the levels reported for beans from other parts of the world, yet OA contamination appears to be infrequent.

Prevention of ochratoxin A contamination of foodand ochratoxin A detoxification by microorganisms - a review

“…A. niger was also effective. In a study of Leong et al (2007), none of the tested isolates of A. niger produced OTA. Schuster et al (2002) stated that only 3-10% of A. niger strains examined for OTA production were toxinogenic under favourable conditions.…”

Mycotoxin Contamination of Beverages: Occurrence of Patulin in Apple Juice and Ochratoxin A in Coffee, Beer and Wine and Their Control Methods

“…In Brazil, the presence of OTA in coffee beans has been vigorously evaluated with contamination levels varying significantly [94,[110][111][112][113]. OTA has been identified in coffee from various countries around the World, such as Australia [114], France [115,116], India [17], Netherlands [117], Saudi Arabia [118], Switzerland [119,120], and USA [121].…”

Assessment of Ochratoxin A intake due to consumption of coffee and cocoa derivatives marketed in Abidjan (Cte dIvoire)

“…Since the first detection of OTA in green coffee by Levi et al, 1974) other studies have confirmed the presence of this mycotoxin in various coffee-based products, such as roasted coffee and instant coffee (Leoni et al, 2000). OTA has been identified in manufactured coffee from various countries, such as Vietnam (Leong et al, 2007), France (NARI, 2004), India (Gopinandhan et al, 2008), the Netherlands (Van der Stegen et al, 2001), and the Czech Republic (Malir et al, 2014). The reported average Pittet et al (1996) (1.1 µg/kg) and of Prado et al (2000) (1.7 µg/kg).…”