The effect of moisture content on determining corn hardness from grinding time, grinding energy, and near-infrared spectroscopy
2007
Armstrong, P.R. | Lingenfelser, J.E. | McKinney, L.
The Stenvert hardness test was used to determine the energy-to-grind (ETG) and time-to-grind (TTG) of 107 food-grade corn hybrids at different moisture content (MC) levels. ETG and TTG were significantly affected by moisture content. Across hybrids, ETG displayed the most consistent response between 10% and 13% MC wet basis. An equation was developed to adjust ETG and TTG to a common MC level in order to minimize moisture effects on corn-hardness determination. ETG was considered to be the preferable method to measure corn hardness, considering ETG adjustments, based on MC, were more accurate using the developed equation. Results also supported grinding at MC levels between 10% and 13% MC to obtain the most accurate results, as opposed to higher MC levels. Grinder speed effects were also found to be significant but controllable, and the repeatability of ETG and TTG were about the same. Near-infrared reflectance spectroscopy was concurrently evaluated as a method to measure corn hardness in terms of ETG and TTG on whole-kernel and ground material from the grinder. Predictive models were poor using spectra (500 to 1700 nm) of whole-kernel and ground samples. Moisture-correction methods developed in this work allowed samples of corn to be tested over a broader range of MC. This provided more convenience and greater confidence in grinding parameters as a measurement of corn hardness.
显示更多 [+] 显示较少 [-]