Effect of fungal infection on phenolic compounds during the storage of coffee beans

Aims: This work was undertaken to study the effect of Aspergillus infection on phenolic compounds in beans from four cultivars of the coffee plant (Coffea arabica L.). The effects of storage conditions of the coffee beans were also examined. Methodology and results: Beans from four varieties of coffee were artificially infected with three species of Aspergillus: A. niger, A. melleus and A. alliacus, and stored at 0, 8 and 25 ± 2 °C). After 3, 6 and 9 months, the contents of phenolic compounds in the beans were determined using high performance liquid chromatography (HPLC). Conclusion, significance and impact study: The results of this study showed that phenolic compounds were qualitatively and quantitatively higher in the inoculated beans as compared with the uninfected control beans, reflecting a possible induced defense mechanism in the infected beans. Increased storage periods resulted in higher levels of phenols, but the average total, bound and free phenols did not differ between the cultivars tested. Effective control of Apergillus infection in coffee beans can prevent such changes in phenolics that may affect their commercial value.