Theses and Dissertations Collection

Ochratoxin A (OTA) is a toxic and potentially carcinogenic fungal secondary metabolite found in a wide variety of agriculture commodities worldwide. It is stable under most food processing conditions. However, interaction of factors like temperature, moisture, pressure, and presence of food components affect its stability. Reduction of OTA was measured at different temperatures for variable heating times in aqueous buffer solutions. It was found that OTA stability was dependent on temperature, processing time, and pH. Greater than 90% reduction was achieved after 60 min of heating at 200C in pH 7 and 10 while only 60% was lost in pH 4. The extrusion study examined effects of moisture, temperature, screw speed, and die size on OTA reduction. It showed that die size and screw speed had significant effect on reduction. The total reduction ranged 0-28% with maximum being achieved at 180C, 250 rpm, 3mm and 20% moisture content.