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OTA-producing fungi isolated from stored cocoa beans
S Amézqueta1, E González-Peñas, C Dachoupakan
1Organic and Pharmaceutical Chemistry Department, Faculty of Pharmacy, University of Navarra, Pamplona, Spain.
Letters in Applied Microbiology
|June 26, 2009
Summary
Fungal populations in Spanish cocoa beans were identified, revealing that Aspergillus carbonarius isolates produced ochratoxin A (OTA). However, OTA levels in beans did not correlate with the presence of these toxigenic fungi.
Area of Science:
- Food Microbiology
- Mycology
- Food Safety
Background:
- Toxigenic fungi in cocoa beans, particularly their ochratoxin A (OTA) production, remain incompletely understood.
- Contamination of cocoa with mycotoxins like OTA poses a significant food safety risk.
- Effective control strategies require accurate identification of fungal populations and their toxicogenic potential.
Purpose of the Study:
- To identify fungal populations within unroasted cocoa beans stored in Spain.
- To assess the ochratoxin A (OTA)-producing capability of isolated Aspergillus species.
- To investigate the relationship between fungal presence and OTA contamination levels in cocoa beans.
Main Methods:
- Analysis of twenty cocoa bean batches with varying OTA content.
- Isolation and identification of Aspergillus carbonarius and Aspergillus niger aggregate strains.
- Evaluation of the OTA synthesis ability of selected fungal isolates.
Main Results:
- Three Aspergillus carbonarius and thirteen Aspergillus niger aggregate strains were isolated.
- Only Aspergillus carbonarius isolates demonstrated OTA production capabilities.
- No direct correlation was observed between cocoa bean OTA levels and the presence of OTA-producing fungi.
Conclusions:
- Despite the lack of correlation, some A. carbonarius strains exhibited high OTA-producing potential.
- Specific fungal control measures during cocoa bean storage are crucial to mitigate OTA contamination.
- Further research into toxigenic fungi in cocoa is warranted to improve food safety protocols.
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