Stability of uric acid used as an indicator on insect contamination during extrusion of wheat flour
1996
Ghaedian, A.R. | Wehling, R.L.
To determine the stability of uric acid during extrusion, wheat flours were spiked with uric acid such that the samples had a uric acid content of approximately 25 microgram of uric acid per gram of flour. The samples were then extruded on a Brabender single-screw extruder at feed moisture contents of 28, 30, and 32% (db) and temperatures of 120, 140, and 160 degrees C. Uric acid in the extrudates was quantified by reversed-phase high-performance liquid chromatography, using ion-pairing with tetra-butylammnonium phosphate and ultraviolet detection. It was found that 62-80% of the uric acid in flour survived extrusion, depending on the extrusion conditions. On average, about 72% of the uric acid initially present was retained in extruded wheat flour. This high recovery level indicates that uric acid is relatively heat stable and could be used as an indicator of insect contamination in extruded products.
显示更多 [+] 显示较少 [-]