Detection of Mold Growth on Theobroma cacao Utilizing Gas Chromatography and Mass Spectrometry

Open Access
Author:
Anderson, Caitlin Morgan
Area of Honors:
Food Science
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Gregory Ray Ziegler, Thesis Supervisor
  • John Neil Coupland, Honors Advisor
Keywords:
  • food science
  • cocoa
  • mold
Abstract:
The ability to detect the presence of mold growth on Theobroma cacao, or cocoa beans, using gas chromatography/mass spectrometry (GC/MS) was evaluated in this study. Two volatile compounds, 1-octen-3-ol and p-cresol, are associated with molds that characteristically grow on cocoa beans. 1-octen-3-ol is generally produced as a volatile organic compound (VOC) by molds, while p-cresol can be utilized by molds that thrive on cocoa, such as Aspergillus fumigatus, as a carbon and energy source. Chromatograms for 1-octen-3-ol and p-cresol were collected using gas chromatography and mass spectrometry. Additionally, chromatograms from samples of both fresh commercial cocoa beans with no visible mold and pre-moistened commercial cocoa beans with distinct mold growth were analyzed using GC/MS to determine if mold growth on Theobroma cacao can be detected by the presence of 1-octen-3-ol and p-cresol. The results indicate that it is possible to detect characteristic VOCs on Theobroma cacao by identification using MassHunter Software, and that differences in concentration of these volatiles and subsequently the amount of mold growth can be detected by GC/MS analysis.