Grain bulk density as affected by diatomaceous earth and application method
Zlatko Korunic, Stefan Cenkowski and Paul Fields
Postharvest Biology and Technology Vol: 13 Issue: 1 Pages: 81-89.
1998
บทคัดย่อ
The effect of the enhanced diatomaceous earth (EDE) insecticide Protect-It(TM) was studied at different concentrations on the bulk density of wheat, corn, barley, rye and oats at three moisture contents (12, 14 and 15% m.c., dry basis). The greatest changes in bulk density occurred when the concentration of EDE ranged from 50 to 200 parts per million (ppm). At concentrations greater than 500 ppm, bulk density decreased little with increased EDE concentrations. The bulk density reductions in all five grains tested were significantly higher for the grain at a dry basis moisture content of 15% than at 12%. The reduction in bulk density as a result of the EDE application was described mathematically using empirical equations. The bulk density of wheat was measured before and after the wet (suspension) or dry (dust) application at 100 and 300 ppm of EDE under laboratory conditions. The dry application caused a significantly greater reduction in wheat bulk density than did the wet application. Application of only 10 ppm of either marine or fresh-water DE significantly reduced the bulk density (about 1.3¯1.8%, w/w, respectively) of 13.9% m.c. wheat without dockage. Twenty five various DE obtained from different regions of the world were tested for bulk density changes when applied to wheat at various concentrations. All DE decreased wheat bulk density, though there were significant differences between DE. The most active DE formulations against stored grain insects, such as Protect-It(TM), Dryacide®, Insecto®, Dicalite, DE Eu and DiaFil, also had the greatest effect on the bulk density.