United States Department of Agriculture

Agricultural Marketing Service

Federal Grain Inspection Service

U.S. Standards May 1988

Distribution: FGIS, OSP, Industry Originating Office: FMD PPMAB

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Subpart F -- United States Standards for Mixed Grain

Contents

Subpart F -- United States Standards for Mixed Grain 1

Terms Defined 2

Principles Governing the Application of Standards 2

Grades and Grade Requirements 3

Special Grades and Special Grade Requirements 3
Official US Standards for Grain

Mixed Grain

May 1988

Page 2

Terms Defined

§ 810.801 Definition of mixed grain. 

Any mixture of grains for which standards have been established under the United 

States Grain Standards Act, provided that such mixture does not come within the 

requirements of any of the standards for such grains; and that such mixture consists 

of 50 percent or more of whole kernels of grain and/or whole or broken soybeans 

which will not pass through a 5/64 triangular-hole sieve and/or whole flaxseed that 

passes through such a sieve after sieving according to procedures prescribed in FGIS 

instructions.

§ 810.802 Definition of other terms.

(a) Damaged kernels. Kernels and pieces of grain kernels for which standards have 

been established under the Act that are badly ground-damaged, badly weatherdamaged, diseased, frost-damaged, germ-damaged, heat-damaged, insect-bored, 

mold-damaged, sprout-damaged, or otherwise materially damaged.

(b) Foreign material and fines. All matter other than whole flaxseed that passes through 

a 5/64 triangular-hole sieve, and all matter other than grains for which standards have 

been established under the Act, that remains in the sieved sample.

(c) Grades. U.S. Mixed Grain, or U.S. Sample grade Mixed Grain, and special grades.

(d) Heat-damaged kernels. Kernels and pieces of grain kernels for which standards 

have been established under the Act, that are materially discolored and damaged by 

heat.

(e) Sieve. 5/64 triangular-hole sieve. A metal sieve 0.032 inch thick with equilateral

triangular perforations the inscribed circles of which are 0.0781 (5/64) inch in diameter.

Principles Governing the Application of Standards

§ 810.803 Basis of determination.

Each determination of damaged and heat-damaged kernels and the percentage of each

kind of grain in the mixture is made on the basis of the sample after removal of foreign

material and fines. 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 

foreign material and fines.
Official US Standards for Grain

Mixed Grain

May 1988

Page 3

Grades and Grade Requirements

§ 810.804 Grades and grade requirements for mixed grain.

(a) U.S. Mixed Grain (grade). Mixed grain with not more than 15.0 percent of damaged

kernels, and not more than 3.0 percent of heat-damaged kernels, and that otherwise 

does not meet the requirements for the grade U.S. Sample grade Mixed Grain.

(b) U.S. Sample grade Mixed Grain. Mixed grain that:

(1) Does not meet the requirements for the grade U.S. Mixed Grain; or

(2) Contains more than 16.0 percent moisture; or

(3) Contains 8 or more stones that have an aggregate weight in excess of 0.2 percent of

the sample weight, 2 or more pieces of glass, 3 or more Crotalaria (Crotalaria spp.), 2 or

more castor beans (Ricinus communis L.), 8 or more cockleburs (Xanthium spp.) or

similar seeds singly or in combination, 4 or more pieces of an unknown foreign

substance(s) or a recognized harmful or toxic substance(s), 10 or more rodent pellets, 

bird droppings, or an equivalent quantity of other animal filth per 1,000 grams of mixed 

grain; or

(4) Is musty, sour, or heating; or

(5) Has any commercially objectionable foreign odor except smut or garlic; or

(6) Is otherwise of distinctly low quality.

Special Grades and Special Grade Requirements

§ 810.805 Special grades and special grade requirements.

(a) Blighted mixed grain. Mixed grain in which barley predominates and that contains

more than 4.0 percent of fungus-damaged and/or mold-damaged barley kernels.

(b) Ergoty mixed grain.

(1) Mixed grain in which rye or wheat predominates and that contains more than 0.30

percent ergot, or

(2) Any other mixed grain that contains more than 0.10 percent ergot.

(c) Garlicky mixed grain.

(1) Mixed grain in which wheat, rye, or triticale predominates, and that contains 2 or

more green garlic bulblets, or an equivalent quantity of dry or partly dry bulblets in 1,000

grams of mixed grain; or

(2) Any other mixed grain that contains 4 or more green garlic bulblets, or an equivalent

quantity of dry or partly dry bulblets, in 500 grams of mixed grain.
Official US Standards for Grain

Mixed Grain

May 1988

Page 4

(d) Smutty mixed grain.

(1) Mixed grain in which rye, triticale, or wheat predominates, and that contains 15 or

more average size smut balls, or an equivalent quantity of smut spores in 250 grams of

mixed grain, or

(2) Any other mixed grain that has the kernels covered with smut spores to give a 

smutty appearance in mass or that contains more than 0.2 percent smut balls.

(e) Treated mixed grain. Mixed grain that has been scoured, limed, washed, sulfured, or

treated in such a manner that its true quality is not reflected by the grade designation 

U.S. Mixed Grain or U.S. Sample grade Mixed Grain.