Evaluation of <i>Pichia mexicana</i> and <i>Bacillus pumilus</i> in Hastening Fermentation Process and its Resulting Effect on the Quality of Dried Cacao Beans


  • Alexander Joel Gatil Gibe Philippine Centre for Postharvest Development and Mechanization
  • Jester O. Pangan


Cacao beans, Enhancers, Degree of Fermentation, Cacao drying, Ochratoxin A


Microorganisms associated with dried cacao beans collected from Davao City were isolated and identified. The dominant species of yeast and bacteria were chosen to come up with treatments composed either of single or combined microbial enhancers. Candidate enhancers were introduced to freshly harvested cacao beans and were assessed under laboratory conditions. Fermented beans were dried  for 3 days and were assessed for degree of fermentation, fungal load and accumulation of Ochratoxin A.


The two dominant microorganisms identified include one yeast, Pichia mexicana and the bacteria, Bacillus pumilus. The treatment that utilized mixture of both microorganisms were successful in shortening fermentation process from 6 to 4 days while single treatment of either P. mexicana or B. pumilus was insufficient to ferment cacao beans within 4 days.  The mixture of both microorganisms was likewise effective in reducing growth of fungi that are believed to produce mycotoxin. Quality of beans after 3 days of drying revealed that the combined treatment was able to reach acceptable degree of fermentation of >70%. The population of fungi from Aspergillus genera in dried beans found in all treatments did not produce any detectable level of Ochratoxin A. The shortened fermentation period of 4 days and drying of 3 days may have contributed much in the control of Ochratoxin A. It is recommended that field evaluation be carried out to validate results. In the same way, other isolated and identified natural enhancers as a possible component of microbial cocktail be assessed in future undertakings.

Author Biography

Alexander Joel Gatil Gibe, Philippine Centre for Postharvest Development and Mechanization

Chief Science Research Specialist


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How to Cite

Gibe, A. J. G., & Pangan, J. O. (2015). Evaluation of <i>Pichia mexicana</i> and <i>Bacillus pumilus</i> in Hastening Fermentation Process and its Resulting Effect on the Quality of Dried Cacao Beans. Asian Journal of Applied Sciences, 3(5). Retrieved from https://www.ajouronline.com/index.php/AJAS/article/view/3143