Effect of extrusion variables (Moisture Content, Barrel Temperature and Screw Speed) on the reduction of aflatoxins in Maize

摘要

Naturally contaminated maize was extrusion processed for reduction of aflatoxins. The contaminated grains collected from different locations were screened for aflatoxins by Pressure Mini Column. The grains were quantified for aflatoxin content (AFB and AFB) by thin layer chromatography. Maize grains were extrusion processed by co-rotating twin-screw extruder using different extrusion variables; feed moisture (24, 27 and 30%), barrel temperature (140, 170 and 200-C) and screw speed (300, 400 and 500 rpm). Response surface methodology was applied to optimize the processing conditions and to assess the effect of extrusion variables on the reduction of aflatoxins. The maximum reduction of AFB1 (75%) and AFB2 (72.5%) in maize with initial concentration of 78 ppb was obtained at 24% moisture, 171 -C temperature and 369 rpm screw speed. Extrusion processed maize with final aflatoxin concentration of 19 ppb was utilized for preparation of porridge and chapatti with good consumer acceptance.