United States

Department of

Agriculture

Agricultural 

Marketing

Service

Fruit and

Vegetable

Division

Fresh

Products

Branch

United States Standards

for Grades of

Filberts in the Shell

Effective September 1, 1970

(Reprinted - January 1997)
 Compliance with the provisions of these standards shall not excuse failure to comply with the provisions of the 1

Federal Food, Drug and Cosmetic Act, or with applicable State laws and regulations.

1

United States Standards for Grades of Filberts in the Shell 1

Grades 

51.1995 U.S. No. 1.

Application of Standards

51.1996 Application of standards.

Definitions

51.1997 Similar type.

51.1998 Dry.

51.1999 Well formed.

51.2000 Clean and bright.

51.2001 Blank.

51.2002 Split shell.

51.2003 Damage.

51.2004 Reasonably well developed.

51.2005 Badly misshapen.

51.2006 Rancidity.

51.2007 Moldy.

51.2008 Insect injury.

Metric Conversion Table

51.2009 Metric conversion table.

Grade 

§51.1995 U.S. No. 1. 

"U.S. No. 1" consists of filberts in the shell which meet the following requirements: 

(a) Similar type; and, 

(b) Dry. 

(c) Shells: 

(1) Well formed; and, 

(2) Clean and bright. 

(3) Free from: 

(i) Blanks; and, 

(ii) Broken or split shells. 

(4) Free from damage caused by: 

(i) Stains; and, 

(ii) Adhering husk; or, 
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(iii) Other means. 

(d) Kernels: 

(1) Reasonably well developed; and, 

(2) Not badly misshapen. 

(3) Free from: 

(i) Rancidity; 

(ii) Decay; 

(iii) Mold; and, 

(iv) Insect injury. 

(4) Free from damage caused by: 

(i) Shriveling; and, 

(ii) Discoloration; or, 

(iii) Other means. 

(e) Size: The size shall be specified in connection with the grade in terms of minimum diameter,

minimum and maximum diameters, or in accordance with one of the size classifications in Table I. 

TABLE I

Size classifications

Maximum size Minimum size

Will pass through a Will not pass through

round opening of the a round opening of the

following size following size

Round type varieties:

 Jumbo------------------------------- No maximum------------------------- 56/64 inch.

 Large-------------------------------- 56/64 inch----------------------------- 49/64 inch.

 Medium----------------------------- 49/64 inch----------------------------- 45/64 inch.

 Small-------------------------------- 45/64 inch----------------------------- No minimum.

Long type varieties:

 Jumbo------------------------------- No maximum------------------------- 47/64 inch.

 Large-------------------------------- 48/64 inch----------------------------- 44/64 inch.

 Medium----------------------------- 45/64 inch----------------------------- 34/64 inch.

 Small-------------------------------- 35/64 inch----------------------------- No minimum.

(f) Tolerances: In order to allow for variations incident to proper grading and handling, the

following tolerances, by count, are permitted as specified: 

(1) For mixed types. 20 percent for filberts which are of a different type. 

(2) For defects. 10 percent for filberts which are below the requirements of this grade: Provided,

That not more than one-half of this amount or 5 percent shall consist of blanks, and not more than
3

5 percent shall consist of filberts with rancid, decayed, moldy or insect injured kernels, including

not more than 3 percent for insect injury. 

(3) For off-size. 15 percent for filberts which fail to meet the requirements for the size specified,

but not more than two-thirds of this amount, or 10 percent shall consist of undersize filberts. 

Application of Standards 

§51.1996 Application of standards. 

(a) The grade of a lot of filberts shall be determined on the basis of a composite sample drawn

from containers in various locations in the lot. However, any container or group of cantainers in

which the filberts are obviously of a quality, type or size materially different from that in the

majority of containers shall be considered a separate lot, and shall be sampled separately. 

(b) In grading the sample, each filbert shall be examined for defects of the shell before being

cracked for kernel examination. A filbert shall be classed as only one defective nut even though it

may be defective externally and internally. 

Definitions 

§51.1997 Similar type. 

"Similar type" means that the filberts in each container are of the same general type and

appearance. For example, nuts of the round type shall not be mixed with those of the long type in

the same container. 

§51.1998 Dry. 

"Dry" means that the shell is free from surface moisture, and that the shells and kernels combined

do not contain more than 10 percent moisture. 

§51.1999 Well formed. 

"Well formed" means that the filbert shell is not materially misshapen. 

§51.2000 Clean and bright. 

"Clean and bright" means that the individual filbert and the lot as a whole are practically free from

adhering dirt and other foreign material, and that the shells have characteristic color. 

§51.2001 Blank. 

"Blank" means a filbert containing no kernel or a kernel filling less than one-fourth the capacity of

the shell. 

§51.2002 Split shell. 

"Split shell" means a shell having any crack which is open and conspicuous for a distance of more

than one-fourth the circumference of the shell, measured in the direction of the crack. 

§51.2003 Damage. 

"Damage" means any specific defect described in this section; or an equally objectionable variation

of any one of these defects, any other defect, or any combination of defects which materially

detracts from the appearance, or the edible or marketing quality of the filberts. The following

specific defects shall be considered as damage: 

(a) Stains which are dark and materially affect the appearance of the individual shell. 

(b) Adhering husk when covering more than 5 percent of the surface of the shell in the aggregate. 

(c) Shriveling when the kernel is materially shrunken, wrinkled, leathery or tough. 

(d) Discoloration when the appearance of the kernel is materially affected by black color. 

§51.2004 Reasonably well developed. 

"Reasonably well developed" means that the kernel fills one-half or more of the capacity of the
4

shell. 

§51.2005 Badly misshapen. 

"Badly misshapen" means that the kernel is so malformed that the appearance is materially

affected. 

§51.2006 Rancidity. 

"Rancidity" means that the kernel is noticeably rancid to the taste. An oily appearance of the flesh

does not necessarily indicate a rancid condition. 

§51.2007 Moldy. 

"Moldy" means that there is a visible growth of mold either on the outside or the inside of the

kernel. 

§51.2008 Insect injury. 

"Insect injury" means that the insect, frass or web is present inside the nut or the kernel shows

definite evidence of insect feeding.

Metric Conversion Table

§51.2009 Metric conversion table. 

Inches Millimeters (mm)

62/64................24.6 

59/64................23.4 

56/64................22.2 

49/64................19.4 

48/64................19.0 

47/64................18.6 

45/64................17.9 

44/64................17.5 

42/64................16.7 

35/64................13.9 

34/64................13.5