Tesis doctoral de María Aranzazu Perez De Obanos Frieros
Abstract the mycotoxin, ochratoxin a (ota), appears in a wide range of commodities, including coffee. It is deemed to have nephrotoxic, immunotoxic, teratogenic and careinogenic effects. The effect of coffee processinq on the ota levéis has been studied from the first stage (green beans) to the tast stage (coffee brew). Ota has been analyzed using hplc-fld. The limits of detection and the estimated uncertainty valúes were 0.04 mg/kg and 27.9% (k=2.3) for green coffee, 0.04 mg/kg and 25.0 % (k=2.3) for roasted coffee, and 0.01 mg/l and 26.3% (k=2.4) for coffee brew, respectively. Thirty-six green coffee samples, from different origins, were analysed. The highest ota concentration (range 0.64 – 8.05 mg/kg) and the highest percentage of defective beans (7.6%) were found in vietnamese samples. Defective beans contribute in only 3.1% of the total ota amount. Ota level seems to be directly related with caffeine level, but no correlation between ota level and % humidity has been obtained; this is probably due to the low humidity level of the samples. A reduction in the ota levéis was achieved in a heterogeneous way when green samples were roasted (mean 66.5%). Coffee brew was prepared by moka, auto-drip and espresso coffee makers. A reduction of the ota level has been attained in all of the cases: espresso coffee (49.8%), auto-drip (14.6%) and moka brewinq (32.1%). Espresso coffee showed the highest ota levéis due to the highest cotfee/water ratio used. Therefore, the method of brewing plays a key role in the final ota human exposure.
Datos académicos de la tesis doctoral «Presencia de la ocratoxina a en cafe verde influencia del procesado en el contenido final en la bebida del cafe«
- Título de la tesis: Presencia de la ocratoxina a en cafe verde influencia del procesado en el contenido final en la bebida del cafe
- Autor: María Aranzazu Perez De Obanos Frieros
- Universidad: Navarra
- Fecha de lectura de la tesis: 20/12/2004
Dirección y tribunal
- Director de la tesis
- Adela Lopez De Cerain Salsamendi
- Tribunal
- Presidente del tribunal: María rosario fatima Olea serrano
- Francisco José Morales navas (vocal)
- pedro Burdaspal perez (vocal)
- María concepción Cid canda (vocal)