Sample feed grain – Chapter 25 | Official Grain Grading Guide
Determination of dockage
Samples are graded using procedures for sample feed grain when they exceed the Broken tolerances for Mixed Grain.
When a sample is to be graded as sample feed grain,
- Return dockage to the cleaned sample.
- Begin cleaning and dockage assessment using the procedures described in this section.
Dockage is assessed to the nearest 0.1% on all samples.
Normal cleaning procedures
- Using a Boerner-type divider, divide the uncleaned sample to obtain a representative portion.
- Official samples should be at least 1000 grams.
- Unofficial samples must be at least 1000 grams.
- Sieve the sample over the No. 4.5 round-hole hand sieve, using approximately 250 g at a time.
Composition of dockage
- Material that passes through the No. 4.5 round-hole sieve
- Material removed by special cleaning for grade improvement
Cleaning for grade improvement
If the grade of a sample can be improved by additional cleaning, perform the cleaning and add the additional material to dockage. Cleaning for grade improvement can be done at any time after the cleaning assessment has been completed.
- After the cleaning assessment has ben completed, use a No. 6 or a No. 5 buckwheat hand sieve to remove large seeds. Large seeds are removed if their total weight exceeds 3% of the cleaned sample by weight.
- Record the additional cleaning and dockage on inspection records.
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