Using A Density Gradient Column To Determine Wheat Density

Authors

Wendell R. Peters, Kansas Agricultural Experiment Station, Manhattan
Robert Katz, University of Nebraska-LincolnFollow

Date of this Version

February 1962

Comments

Published in CEREAL CHEMISTRY. Used by permission.

Abstract

A wheat kernel placed in a density gradient column will sink until it reaches the level where its average density is equal to that of the liquid at that level. Knowing the density of the liquid as a function of height, one can measure accurately the density of the kernel to three decimal places in about 1 to 2 minutes per kernel. Kernel density ranged from a maximum of 1.416 at 7.5% moisture to a minimum of 1.255 g./cm.³ at 18.5% moisture, for the samples tested. Kernels of a homogeneously selected sample of hard spring wheat (Lee) varied in density from 1.29 to 1.41 g./cm. ³ at 12% moisture. A clear separation of grain infested with rice weevil from non-infested grain was found for larvae 20 days old by using a solution of density 1.26 g./cm.³ Protein and ash content have been found to vary with density, and to pass through a maximum in some cases.