United States

Department of

Agriculture

Agricultural 

Marketing

Service

Dairy

Programs

United States Standards

for Grades of

Nonfat Dry Milk 

(Spray Process)

Effective February 2, 2001
1Compliance with these standards does not excuse failure to comply with the provisions of the

Federal Food, Drug, and Cosmetic Act.

1 February 2, 2001

United States Standards for Nonfat Dry Milk (Spray Process)1

Definitions

§ 58.2525 Nonfat dry milk.

(a) "Nonfat dry milk" is the product obtained by the removal of only water from pasteurized

skim milk. It contains not more than 5 percent by weight of moisture and not more than 11⁄2 percent by

weight of milkfat and it conforms to the applicable provisions of 21 CFR part 131 "Milk and Cream" as

issued by the Food and Drug Administration. Nonfat dry milk covered by these standards shall not

contain nor be derived from dry buttermilk, dry whey, or products other than skim milk, and shall not

contain any added preservative, neutralizing agent, or other chemical.

U.S. Grades

§ 58.2526 Nomenclature of U.S. grades.

The nomenclature of U.S. grades is as follows:

(a) U.S. Extra.

(b) U.S. Standard.

§ 58.2527 Basis for determination of U.S. grade.

(a) The U.S. grade of nonfat dry milk is determined on the basis of flavor, physical

appearance, bacterial estimate on the basis of standard plate count, milkfat content, moisture content,

scorched particle content, solubility index, and titratable acidity.

(b) The final U.S. grade shall be established on the basis of the lowest rating of any one of the

quality factors.
2 February 2, 2001

§ 58.2528 Specifications for U.S. grades.

(a) U.S. Extra Grade. U.S. Extra Grade nonfat dry milk shall conform to the following

requirements (See Tables I, II, and III of this section):

(1) Flavor. Reconstituted nonfat dry milk shall possess a sweet, pleasing, and desirable

flavor, but may possess the following flavors to a slight degree: Chalky, cooked, feed, or flat. See

Table I of this section.

(2) Physical appearance. Nonfat dry milk shall possess a uniform white to light cream natural

color. It shall be free from lumps, except those that readily break up with slight pressure, and be

practically free from visible dark particles. The reconstituted product shall be free from graininess. See

Table II of this section.

(3) Bacterial estimate. Not more than 10,000 per gram standard plate count. See Table III

of this section.

(4) Milkfat content. Not more than 1.25 percent. See Table III of this section.

(5) Moisture content. Not more than 4.0 percent. See Table III of this section.

(6) Scorched particle content. Not more than 15.0 mg. See Table III of this section.

(7) Solubility index. Not more than 1.2 ml., except that product classified as U.S. High-heat

may have not more than 2.0 ml. See Table III of this section.

(8) Titratable acidity. Not more than 0.15 percent (lactic acid). See Table III of this section.

(b) U.S. Standard Grade. U.S. Standard Grade nonfat dry milk shall conform to the

following requirements (See Tables I, II, and III of this section):

(1) Flavor. Reconstituted nonfat dry milk shall possess a fairly pleasing flavor, but may

possess the following flavors to a slight degree: Bitter, oxidized, scorched, storage, or utensil; the

following to a definite degree: Chalky, cooked, feed, or flat. See Table I of this section.

(2) Physical appearance. Nonfat dry milk may possess a slight unnatural color. It shall be

free from lumps, except those that break readily under moderate pressure, and be reasonably free from

visible dark particles. The reconstituted product shall be reasonably free from graininess. See Table II

of this section.

(3) Bacterial estimate. Not more than 75,000 per gram standard plate count. See Table III

of this section.

(4) Milkfat content. Not more than 1.50 percent. See Table III of this section.

(5) Moisture content. Not more than 5.0 percent. See Table III of this section.

(6) Scorched particle content. Not more than 22.5 mg. See Table III of this section.

(7) Solubility index. Not more than 2.0 ml., except that product classified as U.S. High-heat

may have not more than 2.5 ml. See Table III of this section.

(8) Titratable acidity. Not more than 0.17 percent (lactic acid). See Table III of this section.
3 February 2, 2001

Table I.--Classification of Flavor With Corresponding U.S. Grade

Flavor characteristics U.S. extra grade U.S. standard grade

Bitter - S

Chalky S D

Cooked S D

Feed S D

Flat S D

Oxidized - S

Scorched - S

Storage - S

Utensil - S

- = Not permitted S = Slight D = Definite

Table II.--Classification of Physical Appearance With

Corresponding U.S. Grade

Physical appearance

characteristics

U.S. extra

grade

U.S. standard

grade

Dry Product:

 Lumpy

 Unnatural color

 Visible dark particles

Slight

-

Practically free

Moderate.

Slight.

Reasonably free.

Reconstituted Product:

 Grainy - Reasonably free.

- = Not permitted
4 February 2, 2001

Table III - Classification According to Laboratory Analysis With

Corresponding U.S. Grade

Laboratory tests

U.S. extra

grade

U.S. 

standard

grade

Bacterial estimate; Standard plate count; per gram (max) 10,000 75,000

Milkfat content; percent (max) 1.25 1.50

Moisture content; percent (max) 4.0 5.0

Scorched particle content; mg (max) 15.0 22.5

Solubility index; ml (max)

 U.S. High-heat (max)

 1.2

 2.0 

 2.0

 2.5

Titratable acidity (lactic acid); percent (max) 0.15 0.17

§ 58.2529 U.S. grade not assignable.

 Nonfat dry milk shall not be assigned a U.S. grade for one or more of the following reasons:

(a) The nonfat dry milk fails to meet or exceed the requirements for U.S. Standard Grade.

(b) The nonfat dry milk has a direct microscopic clump (DMC) count exceeding 100 million

per gram.

(c) The nonfat dry milk has a coliform count exceeding 10 per gram.

(d) The nonfat dry milk is produced in a plant that is rated ineligible for USDA grading service

or is not USDA-approved.

§ 58.2532 Test methods.

All required tests shall be performed in accordance with DA Instruction No. 918-RL,

"Instruction for Resident Grading Quality Control Service Programs and Laboratory Analysis," Dairy

Grading Branch, Dairy Division, Agricultural Marketing Service, U.S. Department of Agriculture,

Washington, DC 20090-6456; the latest revision of "Official Methods of Analysis of the Association of

Official Analytical Chemists"; or the latest edition of "Standard Methods for the Examination of Dairy

Products", available from the American Public Health Association, 1015 Fifteenth Street, NW,

Washington, DC 20005. 
5 February 2, 2001

Explanation of Terms

§ 58.2537 Explanation of terms.

(a) With respect to flavor:

(1) Slight. Detected only upon critical examination.

(2) Definite. Not intense but detectable.

(3) Bitter. Distasteful, similar to the taste of quinine.

(4) Chalky. A tactual type of flavor lacking in characteristic milk flavor.

(5) Cooked. Similar to a custard flavor and imparts a smooth aftertaste.

(6) Feed. Feed flavors (such as alfalfa, sweet clover, silage, or similar feed) in milk carried

through into the nonfat dry milk.

(7) Flat. Insipid, practically devoid of any characteristic reconstituted nonfat dry milk flavor.

(8) Oxidized. A flavor resembling cardboard and sometimes referred to as "cappy" or

"tallowy”.

(9) Scorched. A more intensified flavor than "cooked" and imparts a burnt aftertaste.

(10) Storage. Lacking in freshness and imparting a "stale" aftertaste.

(11) Utensil. A flavor that is suggestive of improper or inadequate washing and sanitation of

milking machines, utensils, or manufacturing equipment.

(b) With respect to physical appearance:

(1) Practically free. Present only upon very critical examination.

(2) Reasonably free. Present only upon critical examination.

(3) Slight pressure. Only sufficient pressure to disintegrate the lumps readily.

(4) Moderate pressure. Only sufficient pressure to disintegrate the lumps easily.

(5) Grainy. Minute particles of undissolved powder appearing in a thin film on the surface of a

glass or tumbler.

(6) Lumpy. Loss of powdery consistency but not caked into hard chunks.

(7) Natural color. A color that is white to light cream.

(8) Unnatural color. A color that is more intense than light cream and is brownish, dull, or

grey-like.

(9) Visible dark particles. The presence of scorched or discolored specks.
6 February 2, 2001

Supplement to U.S. Standards for Grades of Nonfat Dry Milk (Spray 

Process): U.S. Heat Treatment Classification

§ 58.2538 Basis for obtaining heat treatment classification.

Heat treatment classification is not a U.S. grade requirement except in cases when the higher

solubility index specified for U.S. High-heat product is permitted. In all other instances, product

submitted for USDA grading may be analyzed for heat treatment classification upon request and the

results shown on the grading certificate. Heat treatment classification will be made available only upon

a product graded by USDA.

§ 58.2339 Nomenclature of U.S. Heat Treatment Classification.

The nomenclature of U.S. Heat Treatment Classification is as follows:

(a) U.S. High-heat.

(b) U.S. Medium-heat.

(c) U.S. Low-heat.

§ 58.2540 Basis for determination of U.S. Heat Treatment Classification.

The whey protein nitrogen test shall be used in determining the heat treatment classification as

follows:

(a) U.S. High-heat. The finished product shall not exceed 1.50 mg. undenatured whey protein

nitrogen per gram of nonfat dry milk.

(b) U.S. Medium-heat. The finished product shall exceed 1.50 mg. undenatured whey protein

nitrogen per gram of nonfat dry milk and shall be less than 6.00 mg. undenatured whey protein nitrogen

per gram of nonfat dry milk.

(c) U.S. Low-heat. The finished product shall be not less than 6.00 mg. undenatured whey

protein nitrogen per gram of nonfat dry milk.

§ 58.2541 Test method; whey protein nitrogen.

The whey protein nitrogen test shall be performed in accordance with DA Instruction 918-RL,

"Instruction for Resident Grading Quality Control Service Programs and Laboratory Analysis," Dairy

Grading Branch, Dairy Division, Agricultural Marketing Service, U. S. Department of Agriculture,

Washington, DC, 20090-6456, or the latest edition of "Standard Methods for the Examination of Dairy
6 February 2, 2001

Products," available from the American Public Health Association, 1015 Fifteenth Street, NW.,

Washington, DC 20005.