United States

Department of

Agriculture

Agricultural

Marketing

Service

Fruit and

Vegetable

Division

Processed

Products 

Branch

United States

Standards for

Grades of 

Canned Whole Kernel

(Whole Grain) Corn

Effective December 8, 1999
This is the 5th issue, as amended, of the United States Standards for Grades of Canned

Whole Kernel (Whole Grain) Corn, announced as a Notice in the FEDERAL REGISTER

of November 8,1999 (64 FR 215) to become effective December 8, 1999. This issue

supersedes the 4th issue, which has been in effect since July 1, 1957.

Voluntary U.S. grade standards are issued under the authority of the Agricultural Marketing

Act of 1946, which provides for the development of official U.S. grades to designate

different levels of quality. These grade standards are available for use by producers,

suppliers, buyers, and consumers. As in the case of other standards for grades of

processed fruits and vegetables, these standards are designed to facilitate orderly

marketing by providing a convenient basis for buying and selling, for establishing quality

control programs, and for determining loan values.

The standards also serve as a basis for the inspection and grading of commodities by the

Federal inspection service, the only activity authorized to approve the designation of U.S.

grades as referenced in the standards, as provided under the Agricultural Marketing Act of

1946. This service, available as on-line (in-plant) or lot inspection and grading of all

processed fruit and vegetable products, is offered to interested parties, upon application,

on a fee-for-service basis. The verification of some specific recommendations,

requirements, or tolerances contained in the standards can be accomplished only by the

use of on-line inspection procedures. In all instances, a grade can be assigned based on

final product factors or characteristics.

In addition to the U.S. grade standards, grading manuals or instructions for inspection of

several processed fruits and vegetables are available upon request for a nominal

fee. These manuals or instructions contain detailed interpretations of the grade standards

and provide step-by-step procedures for grading the product.

Grade standards are issued by the Department after careful consideration of all data and

views submitted, and the Department welcomes suggestions which might aid in improving

the standards in future revisions. Comments may be submitted to, and copies of

standards and grading manuals obtained from:

Chief, Processed Products Branch

Fruit and Vegetable Programs, AMS

U.S. Department of Agriculture

STOP 0247, P.O. Box 96456, Rm. 0709, So. Bldg.

Washington, D.C. 20090-6456
United States Standards for Grades of

Canned Whole Kernel (Whole Grain) Corn

Effective December 8, 1999

§52.881 Product description .............................................. 2

§52.882 Varietal types of canned whole kernel corn ........................... 2

§52.883 Color types of canned whole kernel corn ............................. 2

§52.884 Definition of terms ............................................... 2

§52.885 Recommended fill of container ..................................... 6

§52.886 Recommended minimum drained weight ............................ 6

§52.887 Grades ......................................................... 6

§52.888 Factors of quality ................................................ 8

§52.889 Allowances for defects ............................................ 9

§52.890 Sample size ................................................... 10

§52.891 Quality requirements ............................................ 10

Authority: Agricultural marketing Act of 1946, Sec. 203, 205, 60 Stat. 1087, as amended,

1090, as amended (7 U.S.C. 1622, 1624).

Note: Compliance with the provisions of these standards shall not excuse failure to comply

with the provisions of the Federal Food, Drug, and Cosmetic Act, or with applicable State

laws and regulations. 
2

§52.881 Product description.

Canned whole kernel (whole grain) corn, including vacuum packed corn, means the

canned product properly prepared from clean, sound, succulent kernels of sweet corn as

defined inthe Standard of Identityfor Canned Corn(21 CFR 155.130) issued pursuant to the

Federal Food, Drug, and Cosmetic Act.

§52.882 Varietal types of canned whole kernel corn.

(a) Conventional means kernels of sweet corn that convert sugars to starch by

going through distinct stages of maturity-- milk, cream, then dough stages.

(b) Supersweet (shrunken 2) means kernels (or grains) of corn that provide

higher naturally occurring sugar, and/or crisper texture (maybe yellow, white or

combination of each) typical for the variety. These varieties may be slightly

darker in color, and some varieties have slightly tougher pericarp (kernel skin)

than conventional sweet corn.

§52.883 Color types of canned whole kernel corn.

(a) Golden (or yellow) means kernels (or grains) of corn that are predominately

golden (or yellow) and typical for the variety.

(b) White means kernels (or grains) of corn that are predominately light cream in

color and typical for the variety.

(c) Combination yellow and white means any combination of the above

varieties and color types or a bi-colored variety.

§52.884 Definition of terms.

(a) Acceptable quality level (AQL) means the maximum percent of defective

units or the maximum number of defects per hundred units of product that, for

the purpose of acceptance sampling, can be considered satisfactory as a

process average.

(b) Appearance.

(1) Good appearance means the sample unit has a practically uniform

color typical of the varietal or color type.

(2) Reasonably good appearance means the sample unit has a
3

reasonably uniform color typical of the varietal or color type.

(3) Fairly good appearance means the sample unit has a fairly uniform

color typical ofthe varietalor color type. Fairly good appearance limits

the "Lot Grade" to Grade B.

(c) Chaff means bits of internal and external kernel parts.

(d) Cob means tough cellulose material that the kernels of corn grow upon. A

portionof cob material means a piece of cob that may or may notbe attached

to kernel(s) of corn (corn kernels are removed from cob tissue before

making measurements).

(e) Cut means the degree of smoothness of the cut surface of the kernels,

uniformity of depth of cut, chaff, and the degree of freedom from adhering cob

tissue.

(1) Well cut means the product is more than slightly affected by the

presence of ragged cut kernels, torn kernels, chaff, and irregular cut

kernels.

(2) Reasonably well cut means the product is not materially affected by

the presence of ragged cut kernels, torn kernels and irregular cut

kernels.

(3) Fairly well cut means the product is not seriously affected by the

presence of ragged cut kernels, torn kernels, chaff, and irregular cut

kernels.

(f) Damaged kernel means any kernel affected by insect injury, discoloration,

pathological injury, or by other means to the extent that the appearance or

eating quality is materially affected. Seriously damaged kernel means any

kernel affected by insect injury, discoloration, pathological injury, or by other

means to the extent that the appearance or eating qualityis seriously affected.

(g) Defect means any nonconformance of a unit of product from a specified

requirement of a single quality characteristic.

(h) Extraneous vegetable material (EVM) means any harmless vegetable

material, to include, but not limited to: cob; husk; shank and stalk; or silk (any

color).
4

(i) Flavor and odor refers to the palatability of the product. The naturalflavor of

the sweet corn for the varietal type and/or the effect of added natural

sweeteners, salt, or other suitable optional ingredients (Standard of Identity

155.130) are considered in evaluating this factor.

(1) Good flavor and odor means the product has a good characteristic

flavor and odor for the varietal type of canned sweet corn and is free

from objectionable flavors and odors. The number of sample units in a

lot that have "fairly good flavor" shall not exceed the applicable

acceptance number specified in the sample plan contained in the

"Regulations Governing Inspectionand CertificationofProcessedFruits

and Vegetables and Related Products."

(2) Fairly good flavor and odor means the product may be lacking in

good flavor and odor, mayhave a flavortypical of verymature corn, may

have anovercookedflavor or anatypicalflavor caused byprocessing or

post-harvest conditions, butis freefromobjectionable flavorsand odors.

(j) Husk means the fibrous vegetable sheath that surrounds the ear of the corn.

(k) Pulled kernel means a kernel of corn that has been removed from the cob

(with cob tissue attached) such that the appearance or eating quality is

materially affected as shown in examples 5, 6, and 7 of the USDAPhoto-Guide

for Classifying "Cut" and "Pulled" Kernels inCanned and FrozenWhole Kernel

Corn.

(l) Sample unit means the amount of product specified to be used for grading.

For appearance, cut, flavor and odor, tenderness and maturity, and varietal

characteristics this includes the entire drained contents of the container. For

grading EVM this includes 850 grams (30 oz drained weight); for seriously

damagedkernels,damagedkernels and pulled kernels the sample unitis 1000

kernels. The sample unit may be:

(1) The entire contents of a container;

(2) A portion of the contents of a container; or

(3) A combination of the contents of two or more containers.

(m) Shank means the toughstem that attaches the ear of corn to the stalk. Shank

material includes the tough basal portion that is attached to the husk.
5

(n) Silk means the silky hair-like filament of any color.

(o) Stalk means the tough woody main support stem of the corn plant.

(p) Tolerance means the percentage of defective units allowed for a specific

sample size.

(q) Tenderness and maturitymeans tender in texture with characteristics typical

of early stage of development of the kernels for the varietal type(s). 

 

(1) Good tenderness and maturity.

For conventionalsweet corn–cornis tender with a cream texture a pericarp

thatchews easily. The kernels are full and tender, typical of the milk and early

cream stage of maturity. There are three levels of quality within "good

tenderness and maturity": very tender, tender, moderately tender.

For supersweet corn–corn is crisp and may have slightly tough pericarp,

compact internal flesh, thatis associated with plump or full kernels. There are

three levels of quality within "good tenderness and maturity": very tender and

crisp; tender and crisp; and moderately tender and crisp.

(2) Reasonably good tenderness and maturity.

For conventional sweet corn--is typical of the cream stage of maturity but

lacks the attributes for "good tenderness and maturity." Some pericarp

residue may be evident upon chewing. There are two levels of quality within

"reasonably good tenderness and maturity": cream stage and moderate

cream stage. 

For supersweet corn--is corn that lacks tenderness and maybe moderately

dry. Kernels may have a reasonably tough pericarp and occasionally are

dented. There are two levels of quality within "reasonably good tenderness

and maturity": not crisp, not moist; and not crisp, moderately dry, and may

includeoccasionaldented kernels. The number of sample units in a lot that fail

to meet "reasonably good tenderness and maturity" shall not exceed the

applicable acceptance number specified in the sample plan contained in the

"Regulations Governing Inspection and Certification of Processed Fruits and

Vegetables and Related Products" (Reference 109-A-1, 52.38).
6

(3) Fairly tough.

For conventional sweet corn--is corn that is in the dough stage "dry and

chewy". Kernels may be dented, but not woody. Pericarp may be tough but not

very tough.

For supersweet corn--is corn that is dry, chewy corn, with tough but not very

tough pericarp. The number of sample units in a lot that fail to meet "tough"

shall not exceed the applicable acceptance number specified in the sample

plan contained in the "Regulations Governing Inspection and Certification of

Processed Fruits and Vegetables and Related Products."

(r) Unit means a kernel of corn or a significant portion thereof.

§52.885 Recommended fill of container.

The standard for fill of containerisnotincorporatedin the grades of the finished product, since

fill of container, as such, is not a factor of quality for the purposes of these grades. It is

recommended that each container of canned corn be filled as full as practicable without

impairment of quality and that, except for vacuum pack, the product and packing medium

occupy not less than 90 percent of the capacity of the container. The product is considered

"Vacuum Packed" when the liquid in the container [as outlined in 21 CFR 155.130 (a)] is not

more than20 percent of the netweight and the container is closed under conditions creating

a high vacuum.

§52.886 Recommended minimum drained weight. 

The minimum drained weight recommendations found in the Grading Manual for Canned

Whole Kernel Corn are notincorporated in the grades of the finished product, since drained

weight, as such, is not a factor of quality for the purpose of these grades.

§52.887 Grades.

(a) U.S. Grade A is the quality of canned corn that:

(1) Meets the following prerequisites (Table I) in which the canned

corn:

(i) Has similar varietal characteristics;

(ii) Has a good appearance;
7

(iii) Is well cut;

(iv) Has a good flavor and odor; and

(v) Has good tenderness and maturity for the varietal

type.

(2) Is within the limits for defects as specified in Tables II and III as

applicable for the varietal type.

(b) U.S. Grade B is the quality of canned corn that:

(1) Meets the following prerequisites (Table I) in which the canned

corn:

(i) Has similar varietal characteristics;

(ii) Has a reasonably good appearance;

(iii) Is reasonably well cut;

(iv) Has a good flavor and odor; and

(v) Has reasonably good tenderness and maturityfor the

varietal type.

(2) Is within the limits for defects as specified in Tables II and III as

applicable for the varietal type.

(c) U.S. Grade C is the quality of canned corn that:

(1) Meets the following prerequisites (Table I) in which the canned

corn:

(i) Has similar varietal characteristics;

(ii) Has a fairly good appearance;

(iii) Is fairly well cut;

(iv) Has a fairly good flavor and odor; and
8

(v) Is fairly tough for the varietal type.

(2) Is within the limits for defects as specified in Tables II and III as

applicable for the varietal type.

(d) Substandard is the quality of canned corn that fails to meet the

requirements of U.S. Grade C.

§52.888 Factors of quality.

The grade of canned corn is based on requirements for the following quality factors:

(a) Prerequisite quality factors:

(1) Varietal characteristics;

(2) Appearance;

(3) Cut;

(4) Flavor and odor; and

(5) Tenderness and maturity.

(b) Classified quality factors:

(1) Extraneous vegetable material (EVM);

(2) Seriously damaged kernels;

(3) Damaged kernels; and

(4) Pulled kernels.
9

§52.889 Allowances for defects.

TABLE I

PREREQUISITES REQUIREMENTS

PREREQUISITE: GRADE A GRADE B GRADE C

Varietal

characteristics

Similar Similar Similar

Appearance Good Reasonably good Fairly good

Cut Well Reasonably well Fairly well

Flavor and odor Good Good Fairly good

Tenderness and

maturity

Good Reasonably good Fairly tough

TABLE II

AQL's, TOLERANCES, AND ACCEPTANCE NUMBERS FOR EVM

BASED ON 850 GRAMS (30.0 ounces)

Sample Units x Sample Unit Size

1x

850

3x

850

6x

850

13x

850

21x

850

29x

850

Units of Product in Grams 850 2550 5100 11050 17850 24650

Extraneous Vegetable Material (EVM) TOL 1/ AQL Acceptance Numbers

 GRADE A

Cob each cc (0.061 cu in) 2/ 1.41 1.25 0.80 2.05 3.85 7.85 12.35 16.85

Husk each cm2 (0.155 sq. in) 2/ 0.57 0.47 7 17 32 64 99 133

Silk, each 2.54 cm, recorded in inches 3.5 3.2 36 96 184 384 611 835

 GRADE B

Cob each cc (0.061 cu in) 2/ 3.5 3.2 1.8 4.8 9.2 19.2 30.6 41.8

Husk each cm2 (0.155 sq. in) 2/ 1.14 0.99 13 33 62 126 198 270

Silk, each 2.54 cm, recorded in inches 7.0 6.6 68 189 367 774 1235 1693

 GRADE C

Cob each cc (0.061 cu in) 2/ 4.94 4.6 2.45 6.75 13.0 27.3 43.4 59.5

Husk each cm2 (0.155 sq. in) 2/ 1.71 1.5 18 48 91 187 244 402

Silk, each 2.54 cm, recorded in inches 24.5 23.8 222 642 1264 2703 4342 5976

1/ Tolerance for cob is based on each 0.05 cc; for husk--each cm2; and silk--each 9 cm at 11050 grams. 

2/ Corn stalk and shank: If hard and tough, count as cob; if less severe, count as husk. 
10

TABLE III

AQL's, TOLERANCES, AND ACCEPTANCE NUMBERS FOR OTHER DEFECTS 1/

Sample Units x Sample Unit Size 1x

1000

3x

1000

6x

1000

13x

1000

21x

1000

29x

1000

Units of Product by Count 1000 3000 6000 13000 21000 29000

Defects Other than EVM

TOL.

1/

AQL

Acceptance Numbers

 GRADE A

Seriously damaged kernels 0.08 .047 1 3 5 10 15 20

Damaged kernels 0.25 .192 4 10 17 33 51 68

Pulled kernels 0.25 .192 4 10 17 33 51 68

 GRADE B

Seriously damaged kernels 0.25 .192 4 10 17 33 51 68

Damaged kernels 0.50 .409 7 18 33 65 101 136

Pulled kernels 0.42 0.34 6 15 28 55 85 115

 GRADE C

Seriously damaged kernels 0.42 0.34 6 15 28 55 85 115

Damaged kernels 1.00 .867 13 34 64 130 204 277

Pulled kernels 0.67 .562 9 23 43 87 136 184

1/ Based on 1000 x 13 (13,000) kernels. 

§52.890 Sample size.

The sample size used to determine whether the requirements of these standards are met shall be as

specified in the sampling plans and procedures in the "Regulations Governing Inspection and

Certification of Processed Fruits and Vegetables, Processed Products Thereof, and Certain Other

Processed Food Products" (7 CFR 52.1 through 52.83).

§52.891 Quality requirements.

(a) A lot of canned corn is considered as meeting the requirements for quality if:

(1) The prerequisite requirements specified in Section 52.887 are met; and

(2) None of the allowances for the individual quality factors specified in Section 52.889
11

in Table II and III, as applicable are exceeded.

(b) Single sample unit. Each unofficial sample unit submitted for quality evaluation will be

treated individually and is considered as meeting the requirements for quality if:

(1) The prerequisites requirements specified in Section 52.887 are met;

(2) The acceptable quality levels (AQL's) in Section 52.889 in Table II and III, as

applicable for the style are not exceeded.

Dated:

/s/ 

Robert C. Keeney

Deputy Administrator

Fruit and Vegetable Programs