United States

Department of

Agriculture

Agricultural

Marketing Service

Fruit and

Vegetable

Division

Processed

Products Branch

Grading Manual 

for

Frozen Strawberries

May 1992
Frozen Strawberries

May 1992

This manual is designed for Processed Products Branch Personnel of the U.S. Department

of Agriculture. Its purpose is to give background information and guidelines to assist in the

uniform application and interpretation of U.S. grade standards, other similar specifications

and special procedures.

The citation of any data, criteria, techniques, illustrations, copyrighted material, or pictorial

representationaccredited to private authorship is used with the permission of the individuals

or sources cited. Unless a specific reference is cited, the information in this manual has been

compiled or developed from sources available to the public as well as from technical

knowledge of personnel in the Department.

Following the suggested guidelines in this manual does notexcuse failure to comply with the

Federal Food, Drug, and Cosmetic Act or any other applicable Federal or State laws or

regulations.

ExceptforofficialUSDAinspectionaids or devices and color guides (orstandards)produced

under licenseofthe Department, the mentionof any supplier, patented device,product, brand

name or equipment does not imply endorsement by the Department over any other similar,

or equally effective material.

Address inquires to:

Chief, Processed Products Branch

Fruit and Vegetable Division, AMS

U.S. Department of Agriculture

P.O. Box 96456, Rm. 0709, South Building

Washington, DC 20090-6456
Frozen Strawberries

May 1992

i

TABLE OF CONTENTS

I. GENERAL Page

Listing of Needed Instructions ................................. 1

Lot ................................................. 1

On-Line ............................................. 1

Non-Quality Procedures ............................... 1

Drawing the Sample ........................................ 2

Net Weight ................................................ 3

Drained Weight ............................................ 3

Thawing the Product for Grading .............................. 3

Determining Fruit Sugar Ratio ................................ 4

Mold Counting Procedures ................................... 5

Obtaining the Sample Unit ............................. 5

Preparing the Sample Unit ............................. 5

Checking for Mold .................................... 6

Styles ..................................................... 6

II. FACTORS OF QUALITY WHICH ARE PREREQUISITE TO THE GRADE

Flavor and Odor ............................................ 7

Similar Varietal Characteristics ............................... 7

Size of Whole Strawberries .................................. 7

III. FACTORS OF QUALITY WHICH ARE SCORED 

Color ..................................................... 8

Summary of Color Definitions ........................... 10

Defects ................................................... 11

Damaged Strawberries ................................ 11

Harmless Extraneous Material (HEM) .................... 11

Short Stems ......................................... 12

Free From Grit ....................................... 12

Character ................................................. 12

Mushy Strawberries ................................... 12
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Seediness ........................................... 12

IV. SPECIAL SAMPLING SITUATIONS Page

Frozen Verification Sample Units .............................. 13

Borderline Situations ........................................ 14

Lateral Samples ............................................ 14

Marketing Order Grading .................................... 14

Special Size Designation ..................................... 16

Unofficial Samples .......................................... 16

V. SUGGESTED ORDER OF GRADING A SAMPLE

Drawing the Sample ........................................ 17

Net Weight ................................................ 17

Thawing the Product ........................................ 17

Drained Weight ............................................ 17

Prerequisite Quality Factors .................................. 17

Scoreable Quality Factors .................................... 18

VI. ASSIGNING THE GRADE OF A LOT ................................ 19

Sample Unit Grade ......................................... 19

Lot Grade ................................................. 20

Scoring Guide for Sliced Strawberries ......................... 21

Scoring Guide for Whole Strawberries ......................... 22
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I. GENERAL

A. Listing of Needed Instructions. In addition to the U.S. Standards for Grades of

Frozen Strawberries and this Grading Manual, you will need to reference:

1. Lot (Stationary or Moving Lot).

a. Regulations (109-A-1)

b. Sampling Procedures (120-A-1)

c. Condition of Container (125-A-1)

2. On-Line

a. Regulations (109-A-1)

b. In-Plant Inspection (160-A-1)

c. Condition of Container (125-A-1)

d. Inspection and Certification of Fruits and Vegetables Using

Unfrozen Sample Units Drawn During Production (165-A-38)

e. Time Sampling Procedures (120-A-4)*

f. State of California Strawberry Marketing Order (SF-C-93)

g. BelowStandard inQuality and Substandard Sample Units (165-

A-5a)

3. Non-Quality Factors

a. Time Sampling (120-A-5)

b. Net Weight (128-A-10)

c. Fill of Container (128-A-40)

d. Drained Weight (130-A-32)

e. Fruit-Sugar ratio (135-A-1)

f. Certification of Fruit-Sugar Ratio (135-A-2)

g. Brix Measurement (135-A-3)

h. Foreign Material (135-A-5)

i. Inspection Procedure for Foreign Material (172-A-1)

j. The Food Defect Action Levels (172-A-2)

k. Mold Count (135-A-8)

l. Product and Storage Temperature (130-A-41)

m. Thawing (130-A-34)

n. Inspection Procedures (130-A-1)

* Not Applicable for Retail Size Containers of Two Pounds Net

Weight or Less Packed Under the State of California Marketing

Order.
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B. Drawing The Sample - All Styles

1. Draw a sample unit in accordance with "Regulations Governing

Inspectionand Certification" (File Code 109-A-1) Section52.38,Table

II. A sample unit may be drawn using the "Time Sampling Plan" (File

Code 120-A-4), except for retail size containers of two pounds net

weight or less packed under the State of California Marketing Order.

2. Refer to the "U.S. Standards for Grades of Frozen Strawberries,"

§52.1991 under "Procedure to obtain sample unit size for product

grading."

3. To gradethe product(unfrozen) on-line for qualityand non-qualityfactors

when packed in container sizes up to 10 pounds, draw the sample unit

immediately upon its leaving the filling machine. If the sample unit

container is less than 16 ounces, draw sufficient containers to collect a

16-ounce aliquot. When bulk container sizes are being packed, a

sub-sample unit is drawn. Draw this sample from the point in the

processatwhichthe product will notundergo any further changes before

and during final packaging.

4. For Lot Grading container sizes up to 10 pounds, the entire container

should be used for the sample unit.

5. For Lot Grading container sizes over 10 pounds including bulk

containers draw an approximate 3 pound sample unit.

6. The amount of product to used for quality analysis is stated below:

SLICED STYLE: If the sample unit container is less than 16

ounces,use twoormorecontainers to collect

a 16 ounce aliquot. If the sample unit

container is of a size exceeding 16 ounces

use a representative 16 ounce aliquot.

WHOLE STYLE: If the sample unit container is less than 16

ounces,usetwoor more containers to collect

a 16-ounce aliquot. If the sample unit

container exceeds 16-ounces up to

32-ounces use the entire sample unit.
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C. Net Weight

The netweight of frozenstrawberries means the weight of the strawberries and

packing medium, exclusive of the container and wrapper. Netweights should

always be takenonretail containers, as well as containers for school lunchand

government contracts. Net weights are taken on institutional size containers

whenrequested or whenitis suspectedthatcontainersmaynotmeetthe stated

label weight.

D. Drained Weight

Drained weight is not taken routinely on frozen strawberries. However, it may

be determined upon request of the applicant and some states require it

(California). It should be taken when there is evidence of excessive ice

contained in the product.

Procedures for determining drained weights of unfrozen and frozen

strawberries are outlined in File Code 130-A-32. Follow this procedure in all

cases except as stated below.

NOTE: UNDER THE CALIFORNIA MARKETING ORDER FOR

PROCESSINGSTRAWBERRIESTHE DRAINED WEIGHTS

FOR RETAIL SIZE CONTAINERS (2 LBS NET WEIGHT OR

LESS) SHALL BE TAKEN BEFORE FREEZING, AND

REQUIRES THE USEOF A U.S.NO. 4 (4 MESH)SIEVE FOR

DRAINED WEIGHT DETERMINATION. THE MARKETING

ORDER DOES NOT APPLY TO RETAIL CONTAINERS

OVER TWO POUNDS.

E. Thawing the Product for Grading

Retail size packages are placedontrays to thawinunopenedcontainers. When

the product is sufficiently free from ice crystals and readily separable, the

sample unit is ready for grading. Thawing can be expedited by placing the

sealed containers in a bath of running warm water not to exceed 86 degrees

Fahrenheit.
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Sub-samples that are drawn from bulk containers should be thawed using the

same method as retail size packages. No. 10 enamel lined cans with plastic

bags should be used as the sampling containers. If it is necessaryto thawthe

entire container, allow it to thaw unopened in a warm water bath not to exceed

86 degrees Fahrenheit. Directing a flow of warm air from an electric fan on the

unopened containers will hasten the thawing process if a water bath is not

available.

The use of a microwave oven to expedite thawing of frozenstrawberries does

not comply with Branch procedures.

Extreme care should be used to prevent damaging the character of the fruit

whentransferring it to the grading trayfrom the container. If frozen strawberries

show any material increase in oxidation after thawing in the above described

manner, such oxidation should be scored against the product.

NOTE: IT IS VERY IMPORTANT THAT THE GRADE OF FROZEN

STRAWBERRIES IS DETERMINED IMMEDIATELY AFTER

THAWING TO PREVENT OXIDATION. EVALUATION OF

QUALITY SHOULD BEGIN AS SOON AS THE UNITS ARE

SUFFICIENTLY THAWED (UNITS MAY BE SEPARATED

EASILY, AND ARE FREE FROM ICE CRYSTALS).

F. Determining Fruit Sugar Ratio

NOTE: REFERENCE BRANCHFILE CODES 135-A-l,AND135-A-2.

1. Dry Sugar Mix

a. Dry sugar is normally mixed with the fruit as the fruit is moved

through the process to the filler.

2. Liquid Packing Medium

a. With liquid packing medium, sirup is introduced into the

container offruitduring the packing operation. The sirup acts as

a diluent and displaces a proportionate amount of space

otherwise taken up by fruit. Therefore, limitations are made for

the amount of sirup that may be added to any container. The

amount of sirup added should not exceed the amount indicated

by the fruit-sugar ratio.

b. Most of the time, the liquid packing medium is added to the

containers instead of being mixed into the bulk strawberries

ahead of time. Consequently, to check the amount of sirup

actually being added to the filled containers by weight or volume

should be rather easy.

c. Make random checks using a refractometer to confirm the actual

Brix of the in-going sirup.

G. Mold Counting Procedures
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1. Obtaining The Sample Unit

a. Retail size containers - Use the entire contents.

b. Institutional and bulk size containers - Use a 2 pound aliquot. 

NOTE: DO NOT DRAIN BEFORE PULPING.

c. Under on-line conditions mold counts should be determined on

some frozen sample units in case of an improper freezing

process.

2. Preparing The Sample Unit

a. The thawed sample is pulped througha cyclone pulper with .027

inchsize screen. Dismantle the cyclone and scrape any material

adhering to the outside of the screen, adding the material to the

sample unit to be examined for the presence of mold. The

cyclone should be dismantled and washed after each use.

b. Transfer approximately 100 grams of the well mixed pulped

material to a beaker. Add about 15 drops (1/2 mL) of caprylic

alcohol,stirring the mixture verycarefully to dissipate airbubbles.

The slide for microscopic examinationshould be prepared using

the instructions from Branch File Code 135-A-8.

NOTE: THE OUTLET TUBE SHOULD BE POINTING

UPWARDS AND PLUGGED WITHA RUBBER

STOPPER.
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3. Checking for Mold

a. See File Code 135-A-8 SectionIIIfor mold counting procedures.

b. See File Code 172-A-2 for Food Defect Action Levels.

c. For Lot Inspection, record all positive and negative mold count

fields on form FV-140 (Mold Count Record) and attach to score

sheet.

d. For On-Line Inspection, record all positive and negative mold

count fields on form FV-140-1 (Tally Sheet For Mold Counts).

H. Styles

1. Frozen whole strawberries are measured from the largest diameter of

the strawberry at right angles to a straight line running from the stem to

the apex. This can be achieved with the use of Inspection Aid No. 68,

which is designed with holes of the appropriate size specifications. 

a. Small means whole frozen strawberries that measure less than

5/8 inch in diameter.

b. Medium means whole frozen strawberries thatmeasure 5/8 inch

in diameter to and including 1-1/4 inches in diameter.

c. Large means whole frozen strawberries thatmeasure more than

1-1/4 inches in diameter.

NOTE: THETHAWEDBERRIESAREMEASUREDBY

LETTING THEM "FREE-FALL" THROUGH

THE SMALLEST POSSIBLE HOLE IN AID

No. 68.

2. There are no particular style requirements for sliced strawberries other

than each strawberry must showevidence of coming in contact with the

slicing knife. Strawberries may be considered as sliced if they are

halvesor sliced into two or more pieces. An occasional unsliced (whole

strawberry) may be found in the sample unit. Do not take exception to

this, unless the overall appearance of the product is not representative

of "sliced" style.
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II. FACTORS OF QUALITY WHICH ARE PREREQUISITE TO THE GRADE

Somefactorsarenot scoreable qualityfactors, but areequallyimportantinconsidering

the overall qualityof the product. These quality factors are graded independently from

the scoreable quality factors. Assign the appropriate letter grade if it is required.

A. Flavor and Odor

Good flavor and odor means that the product has a pronounced strawberry

flavor and is free from any kind of objectionable off flavor or off odor. A musty

flavor or odor is usually due to the presence of mold or decay. Letter grades A

(Good), C (Fairly Good), or Substandard canbe assigned to the factor of flavor

and odor.

B. Similar Varietal Characteristics

Strawberries used for freezing usually have similar varietal characteristics. In

the event the strawberries are distinctly different in varietal characteristics they

should be classified as Substandard. Grade A is assigned if the strawberries

are similar in varietal characteristics. Substandard is assigned if the

strawberries are not of similar varietal characteristics.

C. Size of Whole Strawberries

1. Whole style strawberries which have more than five percent by count of

strawberries less than five eights (5/8) inch in diameter cannot be

graded above Grade B. U.S. Grades B and C do not have a size

limitation. Only assign Grade A or B to the size quality factor of whole

strawberries. It is not necessary to grade this quality factor below Grade

B.

2. Size is determined only on whole style strawberries. Accuracy of the

determination will depend on the requirements of the applicant and

labeling requirements. If no special size certification is requested or

indicated by labeling use the following methods:

a. Select one or more strawberries that are minimum size for

medium (5/8 inch) and maximum for medium (1-1/4 inch).
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b. Visually segregate the strawberriesthataresmaller than5/8 inch

and larger than 1-1/4 inch and record the percentages. If a

sample unitcontains 90% or more of one size,and notmore than

5% of a larger and/or smaller size, record the size as

represented.

c. Record the general size classification. Example: medium, or

medium and large (mostly medium), etc.

III. FACTORS OF QUALITY WHICH ARE SCORED

Place the thawed sample unit on a flat grading tray, and raise one end to drain the

packing medium to the other end of the tray. Use a table fork to separate those units

whichfall into scoreable categories described in the grade standards (Color, Defects,

and Character). Weigh the separated units and remove the remaining strawberry

material (exclusive of packing medium) from the tray and weigh. The sum of the

weights obtained is the total weight of the strawberry ingredients. 

NOTE: CALCULATE THE PERCENT, BYWEIGHT,OFTHE SEPARATED

SCOREABLE MATERIAL BY DIVIDING THE WEIGHT OF SUCH

MATERIAL BY THE TOTAL WEIGHT OF STRAWBERRY

INGREDIENTS.

A. Color

Strawberries oxidize quite readily and should be examined for color when the

strawberries are "JUST" free from ice crystals. With IQF strawberries, wetting

the strawberry surfaces to remove frost may be preferred over completely

thawing the product. However, some varieties have a very thin pigmentation

layer which in some cases will slough off when water is used. This could

permanently alter the sample unit for accurate color determination. These

varieties should be air-thawed.

Color models of strawberries showing representative interpretations of the

color requirements for individual units are available for review in USDA field

offices. These wax strawberries models should be used frequently when

grading the quality factor of color.
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NOTE: WHEN APPLYING THE MODELS FOR COLOR ANALYSIS,

INSPECTORS MUST KEEP IN MIND EVEN IF THE

STRAWBERRIES MEET MINIMUM REQUIREMENTS

INDIVIDUALLY AS ILLUSTRATED BY THE MODELS, THE

STRAWBERRIES AS A MASS MUST ALSO MEET THE

OVERALLUNIFORMITYOF COLOR REQUIREMENTS FOR

EACH RESPECTIVE GRADE.

THESE MODELS DO NOT REPRESENT EVERY COLOR

VARIATION, HOWEVER, THEY DO REPRESENT

REASONABLE GUIDELINES FOR INTERPRETING THE

STANDARDS AND SHOULD BE USED IN ACCORDANCE

WITH THESE INSTRUCTIONS.

1. Model No. 1 illustrates the bottom limit in lightness for "good

characteristic pink color." The light colored area on this model

represents the approximate area which may be lighter than "good

characteristic pink" to comply with the requirement of "over practically

the entire surface." The white area which frequently occurs at the stem

end as a result of having been covered by the cap should be

disregarded in applying the models.

2. Model No. 2 illustrates the maximum darkness permitted for "good

characteristic red color."

Neither Model No. 1 nor Model No. 2 illustrates the "four-fifths surface

area" referred to in Grades A and B. However, 15 percent in A or 25

percent in B of the strawberries may have less pink to red color than

illustrated by Model No. 1 and be darker than Model No. 2.

This is on condition that not more than 5 percent in Grade A or 10

percent in Grade B may have less than four-fifths of the surface area of

good pink to red color; or be as dark as or darker than Model No. 5; or

have a combination of the above- mentioned conditions.

Strawberries are considered as "reasonably uniform" as required for

Grade A if they meet any one of the following conditions:
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a. No strawberries are present thatare lighter thanModelNo.1and

darker than Model No. 2; or

b. Strawberries may be present that are lighter than Model No. 1

withinthe allowances for GradeA:provided,thatnone are darker

than Model No. 2; or

c. Strawberries may be present that are darker than Model No. 2

withinthe allowances for Grade A: provided, that none are lighter

than Model No. 1.

3. Model No. 3 and Model No. 4 represent strawberries which have less

than four-fifths of the surface area of pink or red color. Strawberries

similar to these models are classed as Substandard.

The actualarea of pigmentationrepresents approximately three-fourths

of the surface area of these two models. Strawberries that are slightly

better thanModels No. 3 and No. 4 (slightly more area of pigmentation)

should be considered as possessing four-fifths of the surface area that

is "good characteristic pink to red color; or characteristic pink to red

color." One hundred percent of such strawberries would be permitted

in Grade C, but included in the 5 percent allowance in Grade A and 10

percent allowance in Grade B.

4. Model No. 4 which has a slightly dull (washed- out) appearance

represents the typical Grade C color hue.

5. Model No. 5 illustrates "materially darkened color" and is classified as

Substandard color.

6. Summary of Color Definitions:

a. "Over practically the entire surface" means at least 90 percent of

the outer surface. This does not include cut surfaces in sliced

style nor small areas at the stem end of the whole strawberry

which may be white to light pink in color.

b. "Materially darkened" means units that are dark chocolate

(brownish-red) in appearance and indicative of over-ripened

strawberries.

c. "Dull gray" strawberries have a washed-out (bleached)

appearance and may possess a pale pink to yellow cast

indicative of under-ripened strawberries.

B. Defects

1. Damaged berries include those damaged by slugs or bird pecks and

may have a large portion of the flesh eaten away. Also included as

damaged berries are:

a. Deformed berries (monkey faced) which usually have small

seedy deposits on the end of the berries. These must be firm or
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hard to be scored. This is generally caused by frost, or injury

received before full growth.

b. Haildamage and scald appear as discolored spots or scabs on

the surface of the berry.

c. Decay usually found in the formof"brownrot" sometimes falls out

of the strawberryas acore. Score rot damaged material and the

affected strawberry as one unit. Strawberries affected with

"rubber rot" are grayish pink in color and very firm, often with a

strong creosote odor. Decay is a good indication that mold may

also be present. Follow Branch File Code 135-A-8 and the

manual section on Mold Counting Procedures.

2. Harmless Extraneous Material(HEM) refers to caps, sepal like bracts,

leaves, etc. For HEM that is measurable by area, determine the total

measurable areabyplacing the materialas closely togetheraspossible

on Branch Inspection Aid Number 30 (Area Measurement Aid).

Separate allowances are provided in the grade standards for HEM that

is not measurable by area.
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3. Short stems under 1/8 inch may be non scoreable. If the stem stub is

sharp or tough, it should be counted. However, if the stub end of the

short stem is tender and not otherwise objectionable, it should not be

counted as a short stem.

4. Free from grit, sand or silt means the product should not contain any of

this material that is readily visible or discernable upon chewing.

Check eachsample (whole and sliced styles) carefully for the presence

of grit, by tasting repeated spoonfuls ofstrawberriesand liquid medium.

In addition, by tilting the grading tray (after removing the strawberries)

grit or sand particles will be seen on the bottom of the tray. When

strawberries are not washed properly grit may be noted in the bottom

end of 30-pound tins. Grit tends to settle to the bottom of the container

before freezing or after thawing.

NOTE: BE ALERT FOR PARTICLES OF SAND, SILT OR

GRIT ON IQF STRAWBERRIES. PARTICLES OF

DIRT MAY BECOME TRAPPED AROUND THE

SEEDS AND MAY NOT BE REMOVED BY NORMAL

WASHING.

C. Character

1. The character of frozenstrawberriesshould beascertainedimmediately

after thawing and the product is free from ice crystals. This can be done

immediately after scoring the color, while determining defects. If frozen

strawberries are allowed to stand for any length of time after thawing,

whole strawberries become soft and flattenout and sliced strawberries

become very soft.

2. Mushy strawberries (whole and sliced styles) are a pulpy mass, badly

frayed or badly disintegrated and cannot readily be picked up with the

tines of a table fork.

3. A partial strawberryis a berryin whole style thatis lessthanthree-fourths

of a whole strawberry.

4. Seediness in strawberries pertains to the amount, size, or condition of

the seeds which may affect the appearance and edibility of the

strawberry unit. Closely-spaced seeds covering 1/3 or more of the

surface area of the unit, or darkened and protruding seeds should be

considered under this factor.

5. Firmness is considered in whole and sliced styles. In whole style

considerable flattening can be expected on the thawed strawberries.

The overall requirement for Grade A is reasonably firm for whole and

sliced styles. Strawberries must be fairly firm to meet Grade B and

Grade C.

IV. SPECIAL SAMPLING SITUATIONS

A. Frozen Verification Sample Units
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1. To meet minimum sampling rates, the total number of sample units

examined each shift must be equal to or exceed the minimum number

required in the single sampling plan or time sampling plan for each lot

size of one grade, style, container size, etc.

2. The required number of sample units may consist of unfrozen sample

units from the processing line and frozen sample units from the cold

storage area. The minimum number of frozen verification sample units

is as follows:

a. One frozen sample unit must be examined from approximately

each 1,000 cases of product packed in 10 ounce to 10 pound

containers and for approximately each 1,000-30 pound cans

and/or for each 100 barrels. A minimum of one frozen sample

unit per shift from each lot of a single grade, style and container

size must be examined regardless of lot size.

b. Suspected or known abnormalhandling or freezing conditions is

reason for an increased sampling rate for frozensamples. If the

product is frozen at more than one location or by more than one

method at one location, verification sample units must be

examined from each.

3. Inselecting the necessaryfrozenverificationsample units,anoccasional

unfrozen line check sample unit should be drawn in duplicate. These

verification sample units are used to check correlation with line check

grading;particularly for the factors of color and character. The duplicate

should bemarked or banded to identifyit with the line checksample unit.

On bulk containers, mark the container from whichthe duplicate sample

unitwas drawn. If the results don't correlate, additional frozen samples

should be checked. Verification sample units may be included in the

minimum number of sample units required for examination of the lot.

NOTE: SEE BRANCH FILE CODE 165-A-38 IF FROZEN

SAMPLES ARE NOT CHECKED.

B. Borderline Situations

When a borderline grade situation exists, it may be desirable to increase the

sampling rate. Check Branch File Code 120-A-4 for optional time sampling

rates for qualityfactors and 120-A-5fortimesampling of the non-qualityfactors.

Do not use lateral samples.

C. Lateral Samples

Whenaprocessordesires lateralsample units to be drawn and checked,these

sample units are to be treated as unofficialsamples. Lateral sample units are

to be used as qualitycontrol informationonly and should not be included onthe

score sheet. Use the following guidelines when lateral sample units are taken:

1. Each lateralsample unitmust be comprised of arecommendedsample

unit size.
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2. All prerequisite and scoreable qualityfactors are to becheckedoneach

sample unit.

3. Grade acceptanceis basedonthe U.S.Standards for Grades ofFrozen

Strawberries and other Branch regulations.

4. Each lateral sample unit stands on its own.

D. Marketing Order Grading

Marketing Order Agreements involving frozen strawberries exist for some

states. The state of California has a Marketing Order which contains

instructions for the inspection of frozen strawberries on retail pack containers

of two pounds or less. These instructions are issued by the Processing

Strawberry Advisory Board located in Watsonville, California.

Under the rules and regulations issued under the California Processed

Strawberry Marketing Order, "No processor shall process retailpacked frozen

strawberries with a drained weight of strawberry ingredients less than 60

percent of the actual net weight."
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Compliance with the drained weight requirements shall be based on the

average drained weight and average netweight of all sample units of the same

container size and quality level covering not more than one shift's production.

The drained weight is determined by draining the sample unit for two minutes

on a U.S. No. 4 (4 Mesh) sieve.

To comply with the California Frozen Strawberry Marketing Order quality

requirements, each individual sample unit shall have a total score of not less

than 85 points, as defined in the U.S. Standards for Grades of Frozen

Strawberries; provided, that no sample unit shall score less than 34 points for

the grade factor of Color; provided, that no sample unitshall score less than34

points for the grade factor of Defects; and provided, that no sample unit shall

score less than 17 points for the grade factor of Character.

The USDA lotacceptance criteria shall apply provided no sample unitfrom the

lothas a total score of less than 80 points; provided thatno sample unitscores

less than 28 points for color, 28 points for defects, and 14 points for character;

and further provided that the average score for all sample units (including

deviants) from the lot shall not be less than 85 points.

The California Processing Strawberry Advisory Board requests that USDA

supply them with data on the drained weights and net weights obtained in

determining compliance with the marketing order. This data is entered daily on

the SummarySheet, Form PSAB-78. This information should be submitted at

the end of each month to the Processing Strawberry Advisory Board. All lots

thatmeetthe drained weightand qualityrequirementsshould be reported to the

Processing Strawberry Advisory Board the end of each week on Form

PSAB-78 (Report of Meeting Lots).

Additional information and forms may be obtained from the California

Processing Strawberry Advisory Board atthe following address. Consult your

supervisor first.

Manager

Processing Strawberry Advisory Board of California

P.0. Box 929

Watsonville, California 95077

Telephone (408) 724-5454
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E. Special Size Designation

Manyrequestsfrom importers and some domestic producers presentlyrequire

thatnumericalsizes notadequately described by the U.S. grade standards be

stated onthe grade certificate. If a request for a grade certificate requires size

designation, state the numerical size requested followed by the size

designation from the U.S. grade standards.

a. Example:

Packer requests size certificationwithaspecificationof 5/8" to 7/8" and

a tolerance of over-sized and under-sized strawberries.

Certification statement if product meets specification:

"Size: 5/8 inch to 7/8 inch (Medium)"

Certification statement if product fails specification:

"Size: ______ Sample Units 5/8 inch to 7/8 inch (Medium)

______ Sample Units ____inch to ____inch[indicate eachsize

designation]"

Certification statement for GRADE if product fails specification:

"Grade: Fails 5/8 inch to 7/8 inch (Medium) [indicate company

______ and Specification No.______ ] for size,Because [state

reasons______]"

F. Unofficial Samples

Branch"Regulations"provide for grading ofsamples submittedbyanapplicant.

Unofficial Samples do not represent a lot.

1. Each "Unofficial Sample" must stand on its own.

2. Each "Unofficial Sample" must contain one (1) recommended sample

unit size (see Regulations Governing Inspection and Certification of

Processed Fruits and Vegetables and Related Products).

3. Grade the sample in accordance with the U.S. grade standards and as

outlined in this manual.
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May 1992

17

V. SUGGESTED ORDER OF GRADING A SAMPLE

All quality factors, scoreable and non-scoreable, stand on their own and are graded

independently. Generally, the scoreable quality factors are analyzed for grade first.

However, it is often convenient to analyze scoreable and non-scoreable factors

simultaneously.

A. Drawing the Sample

Drawa sample unitin accordance with "Regulations Governing Inspectionand

Certification" (File Code 109-A-1) Section52.38,Table II, or a sample unitmay

be drawn using the "Time Sampling Plan" (File Code 120-A-4),exceptforretail

size containers of two pounds net weight or less packed under the State of

California Marketing Order.

Refer to the "U.S. Standards for Grades of Frozen Strawberries", §52.1991

under "Procedure to obtain sample unit size for product grading."

B. Net Weight

The netweight of frozenstrawberries means the weight of the strawberries and

packing medium, exclusive of the container and wrapper.

C. Thawing the Product

It is very important that the grade of frozen strawberries is determined

immediately after thawing as soon as the product is free of ice crystals and is

readily separable. 

NOTE: DETERMINING THE GRADE AS SOON AS POSSIBLE

AFTER THAWING MINIMIZES THE RISK OF OXIDATION.

D. Drained Weight

Procedures for determining drained weights of unfrozen and frozen

strawberries are outlined in File Code 130-A-32.

E. Prerequisite Quality Factors

1. Assign Grade A, C, or Substandard to the prerequisite quality factor,

"Flavor and Odor."

2. Assign Grade A or Substandard to the prerequisite quality factor,

"Similar Varietal Characteristics."

3. Assign Grade A or B to the prerequisite quality factor, "Size" (Whole

Style Only).

F. Scoreable Quality Factors

NOTE: DO NOT USE DECLARED LABEL WEIGHT TO

CALCULATE THE TOTAL WEIGHT AS WEIGHT OF

STRAWBERRY INGREDIENTS.
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May 1992

18

 1. Evaluate and determine the color score immediately after the

strawberries have thawed and are JUSTfree from ice crystals. Use the

USDA approved wax strawberry color models to interpret color

requirements for individual units and the requirements for uniformity as

applied to the mass. (Refer to A-456).

 2. Apply the definitions in the U.S. grade standards for Good Color,

Reasonably Good Color, and Fairly Good Color, for the respective

grades classificationand separate those units thatfall into the following

categories:

a. WHOLE STYLE (percent by count)-Separate those units thatdo

not possess a good characteristic pink to red color over

practically the entire surface. Further separate those units that

have less than 4/5 of surface area that possess a good

characteristic pink or red color, or are materially darkened.

Calculate the percentage by count of scoreable color defects

found in the sample unit to determine the color score. Refer to

the appropriate attached scoring guide for scoring the factor of

color for whole style strawberries.

b. SLICED STYLE (percent byweight) - Separate those slices that

do not possess a good characteristic pink to red color over

practically the entire outer surface (not including cut surfaces).

Further separate those slices thathave less than1/2 of the outer

surface (not including cut surfaces) that possess a good

characteristic pink to red color, or are materially darkened.

Calculate the percent byweight of scoreable color defects found

in the sample unit to determine the color score. Refer to the

appropriate attached scoring guide for scoring the qualityfactor

of color for sliced style strawberries.
Frozen Strawberries

May 1992

19

 3. When you are visually scanning the sample unit for color, observe and

separate pieces of harmless extraneous material. This refers to caps,

sepal-like bracts, leaves, short stems (1/8 inch or less in length), stems

(longer than 1/8 inch in length), weeds and grass, etc.

4. Measurethe totalareaofflatextraneous vegetable materiallyplacing the

material as closely together as possible, on Branch InspectionAid No.

30 (Area Measurement Aid).

 5. Count and record the number of pieces of HEM, other than flat HEM,

such as weeds, grass, short stems and other stems.

 6. Separate and record the percentage by weight of damaged

strawberries. Damaged strawberries include those damaged by insects

or bird damage, deformed strawberries (monkey face), hail damage,

sun scald, scars and decay affected units.

 7. In grading sliced and whole styles, check each sample unit carefully for

the presence of grit, sand or silt material.

 8. Separate and record the percentage, by weight, of mushy and seedy

units in whole and sliced styles.

 9. Separate and record the percentage,by weight, of partial strawberries

in whole style.

10. In whole style, check each sample unit carefully for whole strawberries

that are small size (less than 5/8 inch in diameter).

V. ASSIGNING THE GRADE OF THE LOT

A. Sample unit grade

1. When all sample unit grading and analyses have beencompleted for a

production shift or a designated production run comprising a lot, all

sample unit scores should be totaled and the grade assigned to each

individual sample unit.

2. Be certaina grade is assigned to eachnon-scoreable qualityfactor and

representative score points are assigned to the proper grade

classification for each scoreable quality factor of each sample unit.

Considerationmust be given to all factors with animposed limiting rule.

Note the lowest grade indicated by the score points of all scoreable

quality factors when assigning the score points.

3. Totalthe scorepointsof all the scoreable qualityfactors for eachsample

unit. Note the lowest grade indicated by the minimum total score points

required for the grade (90 points for grade A, 80 points for grade B,

etc.).

4. Assign the appropriate letter grade to each sample unit.
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May 1992

20

a. A sample unitcannotbe assigned a higher grade thanthatof the

lowest prerequisite quality factor.

b. A sample unit cannot be assigned a higher grade than that

indicated by the score points of any scoreable quality factor or

that indicated by the minimum required total score points.

B. Lot Grade

1. Apply the deviant rate to all sample units in the lot as necessary.(Use

BranchFile Code 120-A-4 fortimesampling deviantratesor the deviant

rate for the sample size in the Branch regulations, as applicable).

2. Assign the final grade for the lot.

NOTE: OTHER ON-LINE GRADING ACCEPTANCE

CRITERIA, SUCH AS DEVIANT RUNS, WORSE

THAN DEVIANTS, ETC., MAY APPLY. REFER TO

BRANCH FILE CODES AND REGULATIONS AS

NECESSARY.

3. When strawberries are graded as "STRAWBERRIES PREPARED

FOR FREEZING", and frozen samples are not examined, a final grade

cannot be established for the lot. Refer to BranchFile Code 165-A-38

for certification procedures.

4. Branch "Regulations" provide for grading of samples submitted by an

applicant. UNOFFICIAL SAMPLES do not represent a lot. No lot grade

may be given.
21

 SCORING GUIDE FOR FROZEN SLICED STRAWBERRIES

U.S. GRADE A U.S. GRADE B _1/ U.S. GRADE C _1/ SSTD

COLOR SCORE 40 39 38 37 36 35 34 33 32 31 30 29 28 0 - 27

PERCENT BY WEIGHT _2/

Less than overall pink to red color

REASONABLY UNIFORM FAIRLY UNIFORM VARIABLE

FAILS

GRADE

C

3 6 9 12 15 18 20 23 25 NO LIMIT

PERCENT BY WEIGHT _2/

Less than 1/2 surface pink to red or

materially darkened

0 1 2 3 5 6 8 9 10 11 12 13 15

DEFECT SCORE 40 39 38 37 36 35 34 33 32 31 30 29 28 0 - 27

PERCENT BY WEIGHT _2/

Damage 0 1 2 2.5 3 4 5 5.5 6

FAILS

GRADE

C

HEM By Net Weight

(Sq. inch/16 oz.) 0 1/16 2/16 3/16 4/16 5/16 6/16 7/16 8/16 9/16 10/16 11/16 12/16

Short stems < 1/8 inch 0 4 8 12 16 20 24 28 32 NO LIMIT

Stems > 1/8 inch including: 0 1 2 3 4 5 6

Stems > 1/2 inch including: 0

1

3 4 5 6

Stems > 3/4 inch 0 1

Weeds (Not by area) 0 2

GRIT, SAND, or SILT 0 None present that affects the eating quality Trace

CHARACTER SCORE 20 19 18 17 16 15 14 0 - 13

PERCENT BY WT. _2/

Mushy 5 10 20 25 30 40 50 FAILS

GRADE

Firmness REASONABLY FIRM FAIRLY FIRM C

Disintegration or Seediness Not

affected

Not materially

affected Not seriously affected NO LIMIT

_1/ Limiting rule.

_2/ Strawberry ingredient exclusive of surrounding medium.
22

SCORING GUIDE FOR FROZEN WHOLE STRAWBERRIES

U.S. GRADE A 1/ U.S. GRADE B 2/ U.S. GRADE C 2/ SSTD

COLOR SCORE 40 39 38 37 36 35 34 33 32 31 30 29 28 0 - 27

PERCENT BY COUNT

Less than overall pink to red color

REASONABLY UNIFORM FAIRLY UNIFORM VARIABLE

FAILS

GRADE

C

3 6 9 12 15 18 20 23 25 NO LIMIT

 PERCENT BY COUNT

Less than 4/5 surface pink to red or

materially darkened

0 1 2 3 5 6 8 9 10 11 12 13 15

DEFECT SCORE 40 39 38 37 36 35 34 33 32 31 30 29 28 0 - 27

PERCENT BY WEIGHT 3/

Damage 0 1 3 5 6 8 9 10 11 12

FAILS

GRADE

C

HEM By Net Weight

(Sq. inch/16 oz) 0 1/16 2/16 3/16 4/16 5/16 6/16 7/16 8/16 9/16 10/16 11/16 12/16

Short stems < 1/8 inch 0 4 8 12 16 20 24 28 32 NO LIMIT

Stems > 1/8 inch including: 0 1 2 3 4 5 6

Stems > 1/2 inch including 0

1

3 4 5 6

Stems > 3/4 inch 0 1

Weeds (Not by area) 0 2

GRIT, SAND, or SILT 0 None present that affect the eating quality Trace

CHARACTER SCORE 20 19 18 17 16 15 14 0 - 13

 PERCENT BY WT. 3/

 Partial and Mushy 2 5 10 15 20 25 30 FAILS

GRADE

 Firmness REASONABLY FIRM FAIRLY FIRM C

 Disintegration or Seediness Not

affected

Not materially

affected Not seriously affected NO LIMIT

1/ May not contain more than 5%, by count, berries under 5/8 inch in diameter.

2/ Limiting rule.

3/ Strawberry ingredient exclusive of surrounding medium.