Mikoflora Biji Kakao Fermentasi dan Tanpa Fermentasi serta Perbedaan Kerentanannya terhadap Produksi Okratoksin A dan Aflatoksin pada Sistem Inkubasi Kondisi Ekstrim

• Main Authors: , HENI ADHIANATA, , Prof. Dr. Ir. Sardjono, M.S.
• Format: Theses and Dissertations NonPeerReviewed
• Published: [Yogyakarta] : Universitas Gadjah Mada 2014
• Subjects: ETD
• Online Access: https://repository.ugm.ac.id/131041/; http://etd.ugm.ac.id/index.php?mod=penelitian_detail&sub=PenelitianDetail&act=view&typ=html&buku_id=71482
• Institution: Universitas Gadjah Mada

Most of Indonesia�s cocoa beans has been produced through fermentation. Various metabolite end products such as alcohol, lactic acid, and acetic acid are produced during cocoa beans fermentation. These metabolites would induce different chemical characteristic of fermented cocoa beans. Lactic and acetic acid are fermentation products with antimicrobial activity and capable to suppress fungal growth. In the other hand, ochratoxin A (OTA) and aflatoxins (AFs), mycotoxins produced by mycoflora Aspergillus and Penicillium species, usually found as cocoa beans contaminants. The maximum levels of aflatoxins set by European Commision (EC) in food for direct consumption are 2 μg/kg for AFB1 and 4 μg/kg for the sum of AFs and 2μg/kg for OTA in cocoa beans. This study was the first research on fermented and unfermented cocoa beans mycoflora diversity and their susceptibility difference of OTA and AFs production. In this research, parameters evaluated were mycoflora, OTA, and AFs contamination to determine the correlation between susceptibility of fermented and unfermented cocoa beans on OTA and AFs production and the diversity of mycoflora during storage. To investigate the susceptibility, this research was conducted on storage simulation with extreme condition which was 91% of relative humidity. This study was divided into 2 parts. In part I, enumeration using direct plating method was used to determine the level of cocoa beans mycoflora contamination from field and during extreme condition storage. To investigate the potential of OTA production, and possibility of AFs formed during extreme condition storage, spore suspension of Aspergillus ochraceus (4.32 x 108 cfu/ml) was inoculated in fermented and unfermented cocoa beans with a ratio of 2 ml spore suspension per 100 grams of cocoa beans. Cocoa beans were incubated at 91% RH environment to support mycoflora growth and OTA and AFs production. In part II, enumeration using dilution and plating method was used to monitor the growth of inoculated A.ochraceus and other species population which grow during extreme incubation system. Enumeration result indicated that mycoflora contamination in unfermented cocoa beans was higher than those in fermented cocoa beans during extreme incubation system. Mycoflora identification result showed the presence of Aspergillus, Penicillium, Rhizopus, Mucor, and Eurotium. Fermented cocoa beans were more susceptible to AFs production with dominant contaminants from flavus group. The highest AFs production was found in fermented inoculated cocoa beans after 10 days storage. Unfermented cocoa beans were more susceptible to OTA production with dominant contaminants from black Aspergilli. The highest OTA production was found in unfermented inoculated cocoa beans after 15 days storage.