Corn Grading Procedures: Part 2

Principles Governing the Application of Standards

Basis of determining Each determination of class, damaged kernels, heatdamaged kernels, waxy corn, flint corn, and flint and dent corn is made on the basis of the grain after the removal of the broken corn and foreign material. Other determinations not specifically provided for under the General Provisions are made on the basis of the grain as a whole, except the determination of odor is made on either the basis of the grain as a whole or the grain when free from broken corn and foreign material.

Special grades and special grade requirements
(a) Flint corn. Corn that consists of 95 percent or more of flint corn.
(b) Flint and dent corn. Corn that consists of a mixture of flint and dent corn containing more than 5.0 percent but less than 95 percent of flint corn.
(c) Infested corn. Corn that is infested with 2 or more live weevils, 1 live weevil and 5 other live insects injurious to stored grain or 10 live insects injurious to stored grain.
(d) Waxy corn. Corn that consists of 95 percent or more waxy corn according to procedures prescribed in FGIS instructions.

Grade corn as follows:
Step 1. Examine the sample for heating, odor, animal filth, castor beans, crotalaria seeds, glass, insect infestation, stones, unknown foreign substances, and other unusual conditions.
Step 2. Divide out a representative portion from the sample and determine its moisture content.
Step 3. Determine the test weight per bushel of the sample.
Step 4. Determine the percentage of broken corn and foreign material (BCFM) in the sample.
Step 5. When deemed necessary, divide out representative portions from the BCFM-free sample and determine the percentage of class, damaged kernels, flint corn, flint and dent corn, heat-damaged kernels, and waxy corn.

Portion Sizes
The recommended minimum portion size is as follows:
Damaged kernels: 125 grams
Dockage: NA
Foreign material: 250 grams
Heating: The lot as a whole.
Infestation: The original sample or lot as a whole.
Moisture: The amount recommended by the instrument manufacturer.
Objectionable odors: The original sample or lot as a whole.
Test weight per bushel: An amount sufficient to cause grain to overflow a kettle.