Mold growth and ochratoxin a formation in coffee beans | |
| Author | Vo Thi Kim Oanh |
| Call Number | AIT Thesis no.FB-04-14 |
| Subject(s) | Coffee--Storage Aspergillus |
| Note | A thesis submitted in partial fulfillment of the requirement for the degree of Master of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. FB-04-14 |
| Abstract | The effect of moisture contents on mold growth and ochratoxin A formation in coffee storage as well as the effect of drying and roasting on ochratoxin A reduction were studied. Based on both dilution and morphology method> fungi were isolated and identified. Spore solution of Aspergillus ochraceus and Aspergillus carbonarius were incubated in coffee bean at different moisture contents 15%MC> 20%MC> 25%MC and 30%MC in 3 weeks. The same experiment was done with Aspergillus ochraceus at 30%MC in 5 weeks. IUPAC/AOAC method was used in extracting ochratoxin A Quantitative ochratoxin A concentration was determined by Thin Layer Scanner 3 and HPLC. The conclusions drawn from the study were: 13 fungi isolated from coffee bean belonged to Aspergillus and Penicillium genus. Aspergillus ochraceus and three strains of Aspergillus niger were identified. Aspergillus carbonarius did not produce ochratoxin A in all treatments. Aspergillus ochraceus produced ochratoxin A in PDB liquid medium and in incubated coffee bean at 30% of moisture content with the toxin at the levels ranging from 0.04 to 9.8 ng/g. Non ochratoxin A was detected after drying at 60°C, for 12 hours and roasting at 220°C for 10> and 15 min by Thin Layer Chromatography. By using HPLC> it was observed that ochratoxin A results were positive after drying and negative after roasting. |
| Year | 2004 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. FB-04-14 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Food Engineering and Bioprocess Technology (FB) |
| Chairperson(s) | Athapol Noomhorm |
| Examination Committee(s) | Jindal, Vinod K.;Rakshit, Sudip K. |
| Scholarship Donor(s) | The Ministry of Education and Training Vietnam |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2004 |