United States Standards

for Grades of Muscadine

(Vitis rotundifolia)

Grapes

Effective February 13, 2006

United States

Department of

Agriculture

Agricultural 

Marketing

Service

Fruit and

Vegetable

Programs

Fresh

Products

Branch
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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.

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United States Standards for Grades of Muscadine (Vitis rotundifolia) Grapes 1

Effective February 13, 2006

Grades

51.790 U.S. Extra No. 1.

51.791 U.S. No. 1.

Tolerances 

51.792 Tolerances.

Application of Tolerances

51.793 Application of tolerances.

Standard Pack

51.794 Standard pack.

Color Requirements

51.795 Color requirements.

Definitions 

51.796 Good soluble solids.

51.797 Similar varietal characteristics.

51.798 Mature. 

51.799 Not excessively soft.

51.800 Clean.

51.801 Overripe.

51.802 Damage.

51.803 Serious damage. 

Grades 

§51.790 U.S. Extra No. 1.

Any lot of grapes may be designated as “U.S. Extra No. 1” when the grapes meet the

requirements of U.S. No.1: Provided, That in addition to these requirements, 90 percent by

count of the containers in the lot meet the requirements of Standard pack.

§51.791 U.S. No. 1.

"U.S. No. 1 consists of individual grapes or multiple grapes attached by a capstem, which meet

good soluble solids and the following requirements: 

(a) Basic requirements for berries:

(1) Similar varietal characteristics (except when designated as assorted varieties);

(2) Mature;

(3) Well colored;

(4) Clean;

(5) Not excessively soft;

(6) Not dried; 

(7) Not excessively wet from juice;

(8) Not crushed, split or leaking; and,

(b) Free from: 
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(1) Decay;

(2) Mold; 

(3) Insect larvae or holes caused by them; 

(4) Overripe;

(5) Free from damage by any other cause. (See §51.802.) 

(c) Stems free from:

(1) Mold

(2) Decay

(d) For tolerances see §51.792. 

Tolerances

§51.792 Tolerances. 

In order to allow for variations incident to proper grading and handling, the following tolerances,

by count, or equivalent basis are provided as specified: 5 percent tolerance for berries which are

seriously damaged by pulled stems. Additionally, 10 percent for berries which fail to meet the

requirements for the grade: Provided, That included in this amount not more than 5 percent

shall be allowed for defects causing serious damage, including in this latter amount not more

than 2 percent for berries affected by mold or decay. 

Application of Tolerances

§51.793 Application of tolerances. 

Individual samples shall have not more than double the tolerances specified, except that at least

two defective berries may be permitted in any sample: Provided, that the average for the entire

lot are within the tolerances specified for the grade. 

Standard Pack

§51.794 Standard pack.

Berries packed as U.S. Extra No. 1 grade shall be fairly uniform in size. 

(a) “Fairly uniform in size” means that not more than 10 percent, by count of the berries in the

sample may vary more than 3/8 inch in diameter.

(b) “Diameter” means the greatest dimension of the berry measured at right angles to a line from

the stem to blossom end of fruit.

Color Requirements

§51.795 Color requirements.

(a) “Well colored” means in the case of:

(1) “Black and red varieties” that 75% of the surface of the berry shows characteristic color for

the variety. 

(2) “White varieties.” No requirement, except that Carlos, Fry or similar varieties must show

any amount of blush or bronze color on the berry. 

(b) “Characteristic color” means in the case of:

(1) “Black varieties” colors include reddish purple, purple and black.

(2) “Red varieties” colors include light pink, pink, red, dark red and purple.

(3) “White varieties” colors include light green, straw, amber and bronze. Some amount of

blush or pink color may also be characteristic for certain varieties.

Definitions 

§51.796 Good soluble solids.
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“Good soluble solids” means the combined juice from the least mature berries, as determined by

use of a standard hand refractometer shall be at least 13 percent. No lot shall be considered as

failing to meet these requirements unless the composite juice sample from grapes of two

containers or two consumer units, which appear to have the least mature grapes, test below 13

percent soluble solids. The minimum percentage for soluble solids for any lot shall be

determined from the containers with the least mature berries. 

(a) For grapes packed in consumer units, the minimum percentage of soluble solids shall be

determined from the juice of all the berries in the consumer unit.

(b) For all other containers, the minimum percentage of soluble solids shall be determined from

the juice of at least 10 percent, by weight of the berries of the least mature grapes in that

container. 

§51.797 Similar varietal characteristics. 

"Similar varietal characteristics" means that the berries in any container are similar in color and

shape. 

§51.798 Mature. 

"Mature" means that the grapes have reached that stage of maturity in which the flesh is juicy

and palatable.

§51.799 Not excessively soft.

“Not excessively soft” means the berry is reasonably firm and does not yield excessively to

moderate pressure. A slight softening is required for optimum flavor.

§51.800 Overripe.

“Overripe” means that the individual berry is dead ripe, the flesh is soft, mushy and will not

spring back to its original shape. Overripe berries are past commercial utility.

§51.801 Clean. 

"Clean" means that the berries are practically free from spray residue, or other foreign material,

and are not caked with dirt, or showing evidence of lying on the ground.

§51.802 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 fruit. The

following specific defects shall be considered as damage: 

(a) Discoloration, Scars and Powdery Mildew scarring, when excessively deep or rough or dark

colored and aggregate more than 10 percent of the surface of the berry, or when smooth or fairly

smooth, light colored and superficial and aggregate more than 15 percent of the surface of the

berry.

(b) Foreign material, when excessive amounts of leaves, loose stems or other foreign material is

loose in containers and readily noticeable, the sample will be considered damaged, and scored

against a lot tolerance of 20 percent.

(c) Any amount of characteristic speck type or smooth net-like russeting shall be permitted. 

Russeting which exceeds the following shall be considered as damage:

(1) Rough or thick russeting when the aggregate area exceeds 10 percent of the surface of the

berry;

(2) Fairly smooth, and smooth solid russeting when the aggregate area exceeds 15 percent of the
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surface of the berry.

(d) Insects when present, or when the appearance is materially affected by any insect. 

(e) Skin breaks exclusive of pulled stems, when not well healed or when the appearance of the

berry is materially affected.

(f) Excessively wet berries when the individual berry is excessively wet from juice from crushed,

leaking or decayed berries. 

(g) Decayed stems.

§51.803 Serious damage. 

"Serious 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 seriously detracts from the appearance or the edible or marketing quality of the

fruit. The following specific defects shall be considered as serious damage: 

(a) Decayed berries.

(b) Moldy berries.

(c) Overripe berries.

(d) Insect larvae or holes caused by them.

(e) Russeting which exceeds the following shall be considered as serious damage:

(1) Rough or thick russeting when the aggregate area exceeds 25 percent of the surface of the

berry;

(2) Fairly smooth, smooth solid and when the aggregate area exceeds 50 percent of the surface of

the berry.

(f) Discoloration, Scars or Powdery Mildew scars when excessively deep or rough or dark

colored and aggregate more than 25 percent of the surface of the berry, or when smooth or fairly

smooth, light colored and superficial and aggregate more than 50 percent of the surface of the

berry.

(g) Skin breaks exclusive of pulled stems which are not well healed.

(h) Pulled stems when the flesh is excessively torn or which causes the berry to leak. Pulled

stems which are dry, superficial or well healed shall not be considered a defect.

(i) Spotted berries when spots are reddish brown to black in color. Score when individual spot is

greater than 1/8 inch in diameter, or when more than one spot is present.