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Frozen Asparagus 

Inspection Instructions

September 2015
Non-Discrimination Policy: The U.S. Department of Agriculture (USDA) prohibits discrimination against its customers, employees, 

and applicants for employment on the bases of race, color, national origin, age, disability, sex, gender identity, religion, reprisal, and 

where applicable, political beliefs, marital status, familial or parental status, sexual orientation, or all or part of an individual's income 

is derived from any public assistance program, or protected genetic information in employment or in any program or activity 

conducted or funded by the Department. (Not all prohibited bases will apply to all programs and/or employment activities.) To File 

an Employment Complaint: If you wish to file an employment complaint, you must contact your agency's EEO Counselor (PDF) 

within 45 days of the date of the alleged discriminatory act, event, or in the case of a personnel action. Additional information can be 

found online at http://www.ascr.usda.gov/complaint_filing_file.html. To File a Program Complaint: If you wish to file a Civil Rights 

program complaint of discrimination, complete the USDA Program Discrimination Complaint Form (PDF), found online at 

http://www.ascr.usda.gov/complaint_filing_cust.html, or at any USDA office, or call (866) 632-9992 to request the form. You may 

also write a letter containing all of the information requested in the form. Send your completed complaint form or letter to us by mail 

at U.S. Department of Agriculture, Director, Office of Adjudication, 1400 Independence Avenue, S.W., Washington, D.C. 20250-

9410, by fax (202) 690-7442 or email at program.intake@usda.gov. Persons with Disabilities: Individuals who are deaf, hard of 

hearing or have speech disabilities and you wish to file either an EEO or program complaint please contact USDA through the 

Federal Relay Service at (800) 877-8339 or (800) 845-6136 (in Spanish). Persons with disabilities who wish to file a program 

complaint, please see information above on how to contact us by mail directly or by email. If you require alternative means of 

communication for program information (e.g., Braille, large print, audiotape, etc.) please contact USDA's TARGET Center at (202) 

720-2600 (voice and TDD).
These instructions contain information and guidelines to help personnel of the 

U.S. Department of Agriculture’s (USDA) Specialty Crops Inspection (SCI) Division 

uniformly apply and interpret U.S. grade standards, other similar specifications, and 

special procedures.

These guidelines do not supersede the Federal Food, Drug, and Cosmetic Act or any 

other applicable Federal or State laws or regulations. Compliance with these statutes is 

mandatory. This publication supersedes any previously issued inspection instructions.

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

pictorial representations accredited to private authorship is used with the permission of 

the individual(s) or source(s) cited. Unless a specific reference is cited, the information 

in this manual has been derived from sources available to the public or from the 

technical knowledge of USDA personnel.

Except for official USDA inspection aids or devices and color guides (or standards) 

produced under license of the Department of Agriculture, the mention of any supplier, 

patented device, product, brand name, or equipment does not imply endorsement by 

USDA over any other similar or equally effective material.

Inspection instructions are issued by USDA after careful consideration of all data and 

views submitted. The Department welcomes suggestions for improving the inspection 

instructions in future revisions. 

Comments may be submitted to: 

Director, Specialty Crops Inspection Division

Fruit and Vegetable Program

USDA, Agricultural Marketing Service

1400 Independence Avenue, SW, STOP 0240 

Washington, DC 20250

These instructions replace the Instructions for the Inspection of Frozen Asparagus

dated June 1970, and include, but not limited to, all previous correspondence, memos, 

inspection instructions, or procedures.
ii

INSPECTION INSTRUCTIONS FOR FROZEN ASPARAGUS

SECTION PAGE NO.

GENERAL.......................................................................................................................... 1

PRODUCT DESCRIPTION ..................................................................................................... 2

PRODUCTION FLOW ........................................................................................................... 2

INSPECTION AND GRADING ................................................................................................. 3

EQUIPMENT, INSPECTION AIDS, AND INSTRUCTIONS.............................................................. 3

SAMPLE UNIT SIZE............................................................................................................. 3

DEFECT TALLY SHEET FV-364-154E ............................................................................ 4

SIZE DESIGNATION ....................................................................................................... 4

CLASSIFIED QUALITY FACTORS ..................................................................................... 5

COMPLIANCE CRITERIA ................................................................................................. 5

CONTROL CHART ......................................................................................................... 6

CODE SEGREGATION .................................................................................................... 8

WEIGHT ............................................................................................................................ 8

NET WEIGHT................................................................................................................ 8

TEMPERATURE AND CARE OF FROZEN PRODUCT.................................................................. 8

THAWING..................................................................................................................... 8

STYLES............................................................................................................................. 9

TABLE II....................................................................................................................... 9

ILLUSTRATIONS 1 AND 2: FROZEN ASPARAGUS CUT SPEARS (GREEN OR GREEN-WHITE 

TYPE)........................................................................................................................ 10

TYPES ............................................................................................................................ 11

TABLE I: COMPLIANCE WITH GREEN-WHITE TYPE ......................................................... 12

SIZE DETERMINATION....................................................................................................... 13

HOW TO USE THE ASPARAGUS SIZER .......................................................................... 13

SIZE COMPLIANCE...................................................................................................... 14

SINGLE SIZES ............................................................................................................ 15

BLENDS OF SIZES....................................................................................................... 15

MIXED SIZES.............................................................................................................. 16

CLASSIFIED QUALITY FACTORS (DEFECTS)........................................................................ 16

COLOR ...................................................................................................................... 16

UNIFORMITY OF LENGTH............................................................................................ 16

DAMAGE .................................................................................................................... 17

HARMLESS EXTRANEOUS VEGETABLE MATERIAL .......................................................... 17

WHOLESOMENESS (FOREIGN MATERIAL)...................................................................... 18

CHARACTER............................................................................................................... 18
iii

PREREQUISITES ......................................................................................................... 19

LOOSE MATERIAL ....................................................................................................... 20

APPENDIX I STAGES OF DEVELOPMENT IN FROZEN ASPARAGUS.................................. 22

APPENDIX II STAGES OF DEVELOPMENT IN FROZEN ASPARAGUS.................................. 23

APPENDIX III STAGES OF DEVELOPMENT IN FROZEN ASPARAGUS .................................. 24

APPENDIX IV TABLE III ............................................................................................. 25

APPENDIX V TABLE IV ............................................................................................. 27

APPENDIX VI TABLE V.............................................................................................. 29

APPENDIX VIII – EXAMPLE TALLY SHEET AND CONTROL CHART....................................... 31
Inspection Instructions for Frozen Asparagus (September 2015)

1

GENERAL

The United States Standards for Grades of Frozen Asparagus is an Attribute Type 

Standard that is based on a “go” or “no go” acceptance procedure. Deviations in the 

characteristics that denote quality are classified as minor, major, severe, or critical 

depending upon seriousness of the defect. The defects are then tallied, compared to 

acceptance numbers, and the sample is either Grade A, or it fails Grade A, with no 

score points to indicate the relative degree of excellence.

Variations from the quality requirements (color, sizing, damage, texture, harmless 

extraneous vegetable material (HEVM)) are individually classified as defects. These 

defects are described and categorized as minor, severe, or critical, depending upon the 

seriousness of the defect. The sampling plans in the standard are based upon the 

number of defects per hundred units (DHU) rather than percent defective. Under DHU, 

a unit may be scored more than once. 

For example, a single spear may have a minor color defect; a minor length of unit 

defect; a major tough fiber defect; and a severe discoloration defect, for a total of four 

defects:

2 minor defects

1 major defect

1 severe defect

4 total defects – all on one spear

The allowance for the various defect classifications, which are given as cumulative 

acceptance numbers, are statistically geared to specific acceptable quality levels 

(AQL’s) and sample unit size. Any change in AQLs or sample unit size will require a 

corresponding change in the sampling plans (acceptance numbers). Inspectors must 

follow the standard, and the procedures outlined in these instructions.

An exception is buyer specifications, in which AQLs are specified and/or defects are 

classified differently. Inspection and certification cannot be made on these buyers’ 

specifications unless the specifications are available to the inspector and tables of 

acceptance numbers for specified, AQLs included with the specification.

As with any other product, it is acceptable to inspect and certify on the basis of these 

specifications provided that:

• A copy of the written specification is available to the inspector;

• The inspector is able to interpret the specification; and 

• There is no conflict with SCI Division policy.
Inspection Instructions for Frozen Asparagus (September 2015)

2

Many buyers’ specifications include sizing requirements, length of spear or cut, 

limitations on white butts, and re-definitions of quality defects. If the specification uses 

AQLs other than those in the grade standards, the appropriate tables of acceptance 

numbers must be a part of the package given to the inspector. The same policy applies 

to any classification of defects that are different than those provided in the grade 

standards.

PRODUCT DESCRIPTION 

Frozen asparagus consists of sound and succulent fresh shoots of the asparagus plant

(Asparagus officianalis). The product is prepared by sorting, trimming, washing, and

blanching as necessary to assure a clean and wholesome product. It is then frozen and

stored at temperatures necessary for preservation.

Asparagus varieties are classified in two groups based principally on color:

Dark green: color types such as those strains that date back to Mary Washington and 

Martha Washington.

Light green: color types are of limited availability and practically all are in the fresh

market.

As with other vegetables, asparagus hybrids have been developed and it is 

questionable if the exact type can be identified. For freezing purposes, varieties with 

dark green spears are preferred. Often the tips are purplish green.

PRODUCTION FLOW

Asparagus Harvest

Transport

Remove Foreign Material

Washed

Sorted/Cut

Blanched/Cooled
Inspection Instructions for Frozen Asparagus (September 2015)

3

Dewatering

Freeze

Package

Inspect

Ship

INSPECTION AND GRADING

EQUIPMENT, INSPECTION AIDS, AND INSTRUCTIONS

• U.S. Standards for Grades of Frozen Asparagus

• USDA Frozen Asparagus Size Gauge

• USDA Photographic Plates 1, 2, and 3, showing Stages of

Development

• USDA photographs showing defects of workmanship, damage

• AIM Inspection Series Manuals

o Foreign Material Manual

o General Procedures Manual

o Sampling Manual

o Technical Procedures Manual

• FDA Defect Action Level Handbook

• FDA Macroanalytical Procedures Manual – Method V-93

• Defect Tally Sheet (FV-364-154E) and/or Control Charts (intranet link)

SAMPLE UNIT SIZE

Uniformity in the preparation and performance of sampling procedures are a 

fundamental part of Division services. The AIM Sampling Manual provides in depth 

guidance on the procedures and techniques used in sampling frozen asparagus.

Follow the random selection procedures outlined in the AIM Sampling Manual to get a 

proper sample unit in relation to styles:

• For spears and tips – 50 units 

• For cut styles – 100 units
Inspection Instructions for Frozen Asparagus (September 2015)

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DEFECT TALLY SHEET FV-364-154E

Inspection data should be recorded on the Defect Tally Sheet FV-364-154E (intranet 

link) and control chart. The defect tally sheet records detailed information about the 

findings in a sample of frozen asparagus. The tally sheet is to be used for all lot 

inspections and may be used for in-plant inspections. The control chart helps 

production personnel with process control.

Control charts include a key of abbreviations for various types of defects. When a 

particular type of defect becomes prevalent, it may be desirable to set up a separate 

control chart with predetermined limits for that defect only.

After the sample unit has been selected, all defects are counted, properly classified, and 

tallied on the tally sheet. Additional instructions on completing tally sheets may be 

found in the AIM General Procedures Manual in the Score Sheet/Tally Sheet 

Completion section. 

The following is a simple routine tallying procedure:

SIZE DESIGNATION

Sample Unit No. 1

1. For spears or tips, count the number of defects that may be present for size 

(diameter).

2. Record the number of each defect class in the appropriate space on the tally 

sheet opposite size (diameter).

3. Total the above values in the space immediately below opposite cumulative total 

(each class).

4. Add the total number of defects found for all classes and record opposite total (all 

classes).

5. Record the value found in step 4 above in the space opposite cumulative total.

Sample Unit No. 2

1. Repeats steps 1 and 2.

2. Add the number of minor defects found in sample unit No. 2 to the number of 

minor defects found in sample unit No. 1 and record in the minor box opposite 

cumulative total (each class) under sample unit No. 2. Do the same for major 

and severe.
Inspection Instructions for Frozen Asparagus (September 2015)

5

3. Add the total number of defects found in sample unit No. 2 only and record 

opposite total (all classes) under sample unit No. 2.

4. Add the total of all classes recorded for sample unit No. 2 to the total of all 

classes recorded for sample unit No. 1 and record opposite cumulative total (all 

classes) under sample No. 2.

Subsequent Sample Units

Use the same procedure for subsequent sample units as for sample units. 

As for sample unit No. 2 except that the total values of sample unit No. 3 are added to 

the cumulative total values of No. 2, those of No. 4 to No. 3 and so on.

CLASSIFIED QUALITY FACTORS

Defects in the quality factors category include color, length, damage, character, and 

HEVM. Such defects are classified as minor, major, severe, or critical by use of 

objective measurements, photographic illustrations, descriptive terminology, or other 

applicable tests. At the completion of the examination of each sample unit, the defects 

are recorded on the tally sheet in the appropriate boxes. The cumulative totals and 

totals need not be completed until the examination of all sample units is complete, 

except if the tally sheet is being used for in-line control, in which case the entries should 

be completed as the inspection progresses. Recording and adding up the totals and 

cumulative totals follow the same procedures as for size defects.

COMPLIANCE CRITERIA

Criteria for compliance with requirements for size designations and grade are specified 

in the frozen asparagus grade standards. Persons using these standards especially for 

process control purposes should be thoroughly familiar with the acceptance criteria.

The criterion for lot acceptance for a specified size and for quality is as follows:

• The number of defects of the various classes in the first sample unit does not 

exceed the acceptance number specified for total sample. The values for total 

apply to minor defects as well as the sum of minor, major, severe, and critical 

defects.

The absolute limit (AL) is not applicable to the first sample unit.

• The number of defects of the various classes in the second and each subsequent 

sample unit does not exceed the AL value for the applicable class.

• The cumulative number of defects for each class does not exceed the cumulative 
Inspection Instructions for Frozen Asparagus (September 2015)

6

acceptance number for the total sample size for the applicable defect class.

• The cumulative total defects, minor plus major plus severe plus critical, does not 

exceed the cumulative acceptance number for the sample size.

• The amount of loose material does not exceed the allowance for the grade.

• The flavor and odor are normal.

• Varietal characteristics are similar.

• Sand, grit, and silt are within grade limits. 

• The product is wholesome and does not contain foreign material.

• The overall appearance is satisfactory for the respective grade.

If any individual sample unit or the cumulative total fails to meet the acceptance criteria, 

the entire lot fails even though the subsequent sample units are satisfactory. The lot 

may be separated, at the option of the packer or applicant, into meeting and failing 

portions in accordance with segregation procedures outlined in the AIM Sampling 

Manual.

CONTROL CHART

The Control Chart is for use In-Plant for applicants interested in process control. The 

example control chart, appendix I, illustrates the control chart found on the reverse of 

Defect Tally sheet FV-364-154E on which numbers of defects are recorded and plotted. 

Some packers may choose to furnish their own control charts to suit their particular 

needs. Buyers of frozen asparagus may also wish to furnish their own control charts to 

fit their specifications. In any case, the basic design of the defect control chart is the 

same. The difference would be the amount of information desired on the chart or the 

use of different AQLs which would require different AL values.

On the example control chart, the top portion is devoted to size designation (single size 

only). In this case, there is no control chart involved since space would permit only the 

recording of numbers of defects. The procedures for recording the numbers of defects 

and carrying out the cumulative values are the same as those explained for the tally 

sheet except that no separate space is provided for minor defects. The number of 

minor defects is added to the numbers of major and severe defects and recorded as 

Total.

The lower portion of the control chart is devoted to the quality factors. Since the 

frequency of occurrence of critical and severe defects is expected to be rather low, 

these two classes are not set to a control chart. The numbers of defects for these two 
Inspection Instructions for Frozen Asparagus (September 2015)

7

classes and their cumulative values are recorded in a similar manner as explained for 

the tally sheet.

Plotting

The major and minor quality defects are counted, recorded, and plotted as follows:

• Record the number of major defects for each sample unit in the box opposite Ind. 

(Individual) for the appropriate sample unit number on the major chart;

• Plot this value on the corresponding horizontal line on the chart, placing an X 

directly on the line in the center portion of the sample unit column;

• Calculate the cumulative total after each sample unit and record in the box 

opposite Cum. (cumulative) under the appropriate sample unit;

• Do not plot cumulative values.

• Count the number of minor defects and add this value to the sample unit 

numbers of critical, severe, and major;

• Record the value obtained in the box opposite Ind. under the appropriate sample 

unit number on the total chart;

• Plot this value on the appropriate horizontal line for the sample unit as explained 

for major; and 

• Calculate and record the cumulative values for each sample unit.

Interpretation of Plottings and Values

AL values and acceptance values for size and quality factors are listed on the control 

chart for each defect class.

The dash lines on the major and total control charts represent the AL values for the 

respective defect class. These are identified in the left-hand margin of the chart by ALA and AL-B meaning the absolute limit for Grade A, and the absolute limit for Grade B 

respectively.

A lot may be accepted for a specific grade provided: 

• The number of defects for any individual sample unit does not exceed the AL 

value for the defect class and grade. (In the case of major and total, this may be 

readily determined by checking to see that no plotted value X is above the AL 

line for the grade);
Inspection Instructions for Frozen Asparagus (September 2015)

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• The cumulative number of defects does not exceed the cumulative acceptance 

number for the defect class, sample sizes, and grades;

• The flavor and odor are normal; and 

• The amount of loose material, where applicable, does not exceed the allowance 

for such material for the grade.

CODE SEGREGATION

In the case of in-plant inspection, if a lot fails at any time during a production, the entire 

production lot shall fail unless the offending portion can be segregated in accordance 

with current lot segregation procedures in the AIM Sampling Manual.

When a lot is segregated, all values for sample units applicable to the failed, segregated 

portion are removed from the tally sheet or control chart, the remaining portions 

combined, and all cumulative totals recalculated for the remaining portions only. The 

acceptance criterion is again applied to remaining portions.

WEIGHT

NET WEIGHT

Processed foods are commonly packed to meet a prescribed net weight or content, and 

are labeled accordingly. This net weight or content may be specified in a purchase 

specification or contract. In depth instructions on performing net weights may be found 

in the AIM Technical Procedures Manual.

TEMPERATURE AND CARE OF FROZEN PRODUCT

As a prerequisite to assigning the grade to frozen fruits and vegetables, the U.S. 

standards for frozen asparagus state: “frozen and stored at temperatures necessary for 

preservation." 

Interpretive guidance on this statement is found in the Verification of Frozen Sample 

Units section of the AIM Technical Procedures Manual. 

The inspector must make every effort to ensure that when sampling and handling,

procedures do not contribute to broken or shattered units.

THAWING

The product may be thawed in the following ways:

• Air thaw the product in its container at room temperature.
Inspection Instructions for Frozen Asparagus (September 2015)

9

• Water thaw the product in its container or on a screen of suitable size under a fine 

spray of water. The water temperature should not exceed 86° F.

Regardless of the thawing method used, determine the size as soon as the units are 

readily separable and the sample units have been selected for product evaluation.

Insects or extraneous material remaining in the water used for thawing should be 

recovered and evaluated as a part of the sample unit.

Detailed instructions on thawing procedures may be found in the AIM Technical 

Procedures Manual section on Thawing Procedures.

STYLES

Frozen asparagus styles:

• Spears,

• Cut Spears,

• Center Cuts, and 

• Tips.

Record the style of the product on the tally sheet, FV-364-154E.

For cut spears determine the percent of head material on the basis of the 100-unit 

sample and record this information in the appropriate space. The amount of head 

material required in cut spears depends on the length of the cut, as follows:

TABLE II

Length of Cut Sample Average

(Minimum)

Individual Subsample

(Minimum)

11⁄4 inches or less 18% 12%

Longer than 11⁄4 inches 25% 15%

In separating head material, keep in mind that a piece or unit of head material is:

• A tip end of a shoot that is 3/8 inch or more in length; or

• An upper portion of a shoot that contains a substantial amount of compact head 

material.

Substantial Amount means approximately 75 percent or more of the apparent original 

head portion of the shoot. A few bracts staggered down a portion of the cut do not 
Inspection Instructions for Frozen Asparagus (September 2015)

10

qualify the unit as head material. See visual illustrations 1 and 2 of heads or head 

material, cut and loose material below.

ILLUSTRATIONS 1 AND 2: FROZEN ASPARAGUS CUT SPEARS (GREEN OR GREENWHITE TYPE)
Inspection Instructions for Frozen Asparagus (September 2015)

11

TYPES

The U.S. grade standards for frozen asparagus define two types – green or all green, 

and green-white. 

Green or all green asparagus is green or yellowish green the entire length of the unit. 

Green asparagus generally has less fiber and heads are less compact than greenwhite.

Green-white units have a typical green color over most of the unit but are white in the 

lower portions of the stalk. This type is restricted to the styles of spears and tips.

Culturally – bleached (white) asparagus is not frozen.

Nearly all of the asparagus frozen is of the all green type. Inspectors rarely will decide 

whether or not the product complies with the criteria for green-white. Unless the 

product is actually labeled or offered as green-white, consider the product as all green 

type.

When asparagus is declared or offered as green-white type it should have a substantial 

number of spears or tips that meet the definition for this type. This means that the 

number of all green spears or tips present do not exceed the acceptance values for 

absolute limits (AL) or for the sample size in Table I of this Instruction as shown on the 

following page. If the product fails to meet these criteria, it should be considered as all 

green type and graded accordingly.
Inspection Instructions for Frozen Asparagus (September 2015)

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TABLE I: COMPLIANCE WITH GREEN-WHITE TYPE

Absolute Limit (AL) In any sample unit 1

Number of Sample Units Number of Spears or Tips Maximum No. All-Green 

permitted

1 50 12

2 100 21

3 150 30

4 200 39

5 250 47

6 300 55

7 350 63

8 400 72

9 450 80

10 500 90

11 550 96

12 600 104

13 650 112

14 700 121

15 750 129

16 800 140

17 850 145

18 900 153

19 950 161

20 1000 169

21 1050 177

1 In any sample unit, except the first of 50 units.
Inspection Instructions for Frozen Asparagus (September 2015)

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SIZE DETERMINATION

The United Standards for Grades of Frozen Asparagus include size designations for 

spears and tips (as applicable), and state how size (diameter) is to be determined. Size 

determination of spears and tips should be made as soon as possible after the units are 

thawed and can be separated. Otherwise, the shoots may lose rigidity and are more 

difficult to restore to their original conformation for proper measurement.

USDA Inspection Aid 109, Canned and Frozen Asparagus Sizer is a white, opaque 

Plexiglas plate (3” x 8”) with a V shaped notch extending lengthwise which is used to 

measure and classify the size (diameter) of asparagus. One side is marked for frozen

asparagus sizing; the other side is marked for canned asparagus. The right edge of the 

V on each side of the plate includes the diameter dimensions for the respective size 

designations. The diameter dimensions imprinted on the sizer equal the width of the V

at the point indicated by the dimension. One edge on each side is marked off in 1/4-

inch graduations for measuring the length of the asparagus units.

Clean Inspection Aid 109, Canned and Frozen Asparagus Sizer by using mild soap and 

lukewarm water and dry with a soft cloth or towel. Do not use abrasive or strong 

cleaning agents on this inspection aid. Do not soak for extended periods of time.

HOW TO USE THE ASPARAGUS SIZER

It is not necessary to make actual measurements of each unit to ascertain the sizes 

present in any individual sample unit. Separate the units according to diameter, 

grouping those that appear to be of the same diameter. Measure two or three units 

from each size group to establish the sizes and percentages of each size group present. 

Check additional units if needed. The diameter measurements are made with the 

USDA sizer as follows:

• Use the same sample unit for quality determination unless separate in-line 

control is in effect for size only.

• Use the side applicable to the frozen product.

• Insert the asparagus unit into the V so that:

o The asparagus unit length is approximately at right angles to the sizer.

o The greatest diameter of the asparagus unit (after being restored to its 

original shape) is approximately parallel with the end of the sizer; and

o The point of measurement of the asparagus unit is at the point of

maximum diameter, regardless of the length of the shoot.
Inspection Instructions for Frozen Asparagus (September 2015)

14

• Move the asparagus unit down the V until the unit barely makes contact with both 

sides of the V. Do not force the unit beyond this point.

• Classify the size designation of the unit, stated between the diameter divisions, 

with which the unit falls.

Example:

• If a frozen asparagus spear, when measured following the procedures above, 

falls between the 3/8-inch and 5/8-inch diameter divisions, the spear is classified 

as medium size.

• If the diameter falls on a dividing line between two size classifications, consider 

the unit as the larger size.

SIZE COMPLIANCE

Follow the requirements in the grade standards to determine compliance with one of the 

following sizes:

• A single size,

• Blends of two adjacent sizes,

• Blends of three adjacent sizes, or 

• Mixed sizes.

Table I of the standards provides diameters for the respective single sizes according to 

word or number designation.

Table II of the standards specifies defects that may be applicable for a particular single 

size or a blend of specified sizes. Note that these deviations are classified as minor, 

major, or severe. For blends of sizes, a defect can only be minor.

Table III contains the acceptance criteria for single sizes and blends of sizes according 

to sample size and the number and type of defects present. Note that right hand 

column applies to blends only.
Inspection Instructions for Frozen Asparagus (September 2015)

15

SINGLE SIZES

Acceptance criteria are illustrated by the following example:

Example 1 (Medium Size Declared)

Sample size - 300 spears.

Small - 10 spears - Major defect

Large - 11 spears - Minor defect

Extra Large - 9 spears - Severe defect

Total: 30 defects

The sample as a whole meets the criteria for medium size since a sample size of 300 

spears could contain 32 major, 12 severe, and 55 total defects.

Example 2 (Medium Size Declared)

Sample size - 300 spears.

Small - 10 spears - Major defect

Large - 11 spears - Minor defect

Extra Large - 9 spears - Severe defect

Total: 30 defects

BLENDS OF SIZES

The standards define two combinations for blends of sizes. One combination is for a 

blend of two adjacent sizes; the second is for a blend of three adjacent sizes. 

Acceptance criteria are shown in Table III and §52.391 in the same manner as for single 

sizes.

If a sample is found to fail the criteria for either a blend of two or three sizes, the lot is 

considered as Mixture of Sizes.

Example 3 (Lot Declared as Medium-Large Blend)

Sample size - 400 spears

Small - 24 spears - Minor defect

Extra Large - 8 spears - Minor defect

Total: 32 defects
Inspection Instructions for Frozen Asparagus (September 2015)

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The sample as a whole meets the criteria for medium-large blend, as Table III permits 

41 defects for a sample of 400 units. 

MIXED SIZES

If the sample does not meet the criteria for either a single size or blends of sizes, it 

automatically falls into the category of mixture of sizes.

CLASSIFIED QUALITY FACTORS (DEFECTS)

Defects are classified by the degree of severity of the following quality factors: color, 

uniformity of length, character, damage, and harmless extraneous vegetable material

(HEVM).

COLOR

The normal color of frozen asparagus after thawing is:

• Green or all-green – bright green or purplish green, with no tinges of gray or olive 

colors.

• Green-white – the same as green except that white or yellowish-white areas

extend up the stalk from the cut end.

A grayish or olive coloration in frozen asparagus may be caused by over-blanching, 

improper cooling after blanching, holding too long prior to freezing, and other causes. 

Asparagus spears affected in this manner should be considered a major or severe color 

defect, depending upon whether the appearance of the unit is more than slightly but not 

materially affected, major, or materially affected or worse, severe. Other color defects 

are described and classified in the grade standards in Table IV. Color defects are either 

major or severe; there are no minor defects for color. For all-green spears and tips, 

disregard white color not exceeding 1/4-inch.

UNIFORMITY OF LENGTH

Defects for this factor are described and classified in the grade standards in Table IV. 

In the case of spears or tips, the sample unit is laid in a single layer and single row. All 

of the heads or cut ends (i.e., preferable cut ends) should be even. This may be done 

quickly by placing the heads or cut ends against a straight edge of some type. An 

estimation of length is then made from the approximate average length of all of the 

spears or tips with the most uniform lengths. Spears or tips that vary more than 

11⁄2 inches from this approximate average length are considered a minor defect. 

Misshapen units should be straightened when determining the length. 
Inspection Instructions for Frozen Asparagus (September 2015)

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In the case of cut styles, units shorter than 1/2 inch (excluding head material or loose 

material) or more than 2 inches are considered defects for these styles, and classified 

as minor and major respectively.

DAMAGE

Various types of damage are classified according to the degree to which the 

appearance or edibility of the unit is affected. Under this factor there are four subheadings or sub-classifications of damage:

• Shattered heads

• Misshapen

• Poorly Cut

• Discoloration, mechanical injury, pathological injury, other.

Shattered heads – To be considered a defect the head should be shattered or broken to 

the extent that the appearance of the unit is materially affected.

Misshapen – Only spears or tips which are seriously affected in appearance by doubles 

or by crooked units, or other malformations should be scored as a defect.

Poorly cut – Consider as poorly cut units only those units which have very ragged, 

stringy, or frayed edges or a unit that is only partially cut or cut at an angle of less than 

approximately 45 degrees.

Other types of damage – Other types of damage listed in the grade standards include 

discoloration, mechanical injury, pathological injury, or damage by other means. 

Although these types are listed and classified together, it is the intent to consider each a 

separate defect when they are non-related. If they are related defects, or if a clear 

distinction as to cause can’t be made, consider the damage as one (1) defect. 

For example, a unit may be gouged on the stalk and also have considerable insect 

damage on the head. In this case the damage is non-related and the unit is considered 

two defects. In another example, the stalk may have a discolored growth crack and in 

the same area have rust. In this case it is difficult to determine whether or not the two 

conditions are related, and consequently the unit should be scored as one (1) defect 

only. Inspectors should use discretion in scoring a unit more than once for the factor of 

other types of damage.

HARMLESS EXTRANEOUS VEGETABLE MATERIAL

Various types of harmless extraneous vegetable material most commonly encountered 

in frozen asparagus are classified for defects by length. If more than one type of 

harmless extraneous material occurs in one sample unit, they are treated as separate 

defects according to their length. 
Inspection Instructions for Frozen Asparagus (September 2015)

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More than one piece of a single type should be treated as a single defect according to 

the aggregate lengths of the pieces.

WHOLESOMENESS (FOREIGN MATERIAL)

Be alert for foreign matter during the examination of frozen asparagus. This includes 

but is not limited to: wood splinters, paint flakes, weeds, and insects. Ordinarily, careful 

macroscopic or visual examination is sufficient to detect this type of material. However, 

when circumstances warrant (e.g., for insect recovery) extraction, filtration, and 

microscopic examination should be used to determine extent of contamination. 

Detailed instructions on Foreign Material procedures may be found in the AIM Foreign 

Material Manual.

CHARACTER

The factor of character is a combination of development characteristics, tenderness, 

and fiber development. 

Development

The grade standards show photographs of defects related to development for the factor 

of character. Plate 1 and 2 show the bottom limits for a well-developed head and are 

not considered defects. In these cases, growth has progressed to the point where seed 

development has just begun. The lower bracts are slightly elongated but the heads are 

still tight. Asparagus with growth that that has progressed beyond the spears illustrated 

in plate 1, but not beyond the spears illustrated in plates 2 and 3, are considered 

reasonably well developed. Plates 2 and 3 are considered the maximum limits for 

reasonably well developed. Note the seedy appearance of the heads. The bracts have 

elongated, giving the head a slightly loose appearance. The bracts at the tips, however, 

are still fairly compact. Note the slightly sparse appearance of the heads of spears 5, 6, 

and 8 of plates 2 and 3. Reasonably well developed asparagus is considered a defect 

in Grade A only. One-hundred percent of such units are permitted in Grade B. When 

the development of the asparagus has progressed beyond the point illustrated in plates 

2 and 3, the heads may appear seedier and the bracts will be more elongated producing 

a rather loosely structured head. Asparagus in this condition is considered poorly 

developed and is a defect in both Grade A and Grade B.

Tenderness and Texture (Fiber Development)

The tenderness and texture of frozen asparagus is affected by the presence of tough, 

inedible fibers. The development of fiber in asparagus is to be anticipated when the raw 

product is held in the field or processors’ storage for any appreciable period of time. 

Slow growing due to weather conditions may also affect the amount of fiber in the raw 

product. 
Inspection Instructions for Frozen Asparagus (September 2015)

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The tenderness of frozen asparagus may be determined by manually feeling the ends of 

the units, the fork test, or chewing. The presence of fiber should be determined 

throughout the entire length of the unit.

• By rubbing the thumb or finger across the end of cut surface it is possible, with a 

bit of experience, to detect the presence of fibrous material or suspected fibrous 

material. A unit found or suspected to be fibrous should be further examined by 

the fork test and chewing.

• The fork test (after cooking) is accomplished by severing the unit by rocking a 

fork through the product with moderate pressure. The asparagus should cut 

through easily if no tough fiber is present.

• Chewing (after cooking) is the final determination of the presence of fiber in all 

cases. It is possible to find units that feel fibrous or are not completely severed in 

the fork test that do not have tough fibers. Units that chew without noticeable 

fiber are not considered a defect. Instructions and cook times for cooking frozen 

asparagus may be found in the AIM Technical Procedures Manual, Cooking 

Procedures section.

Follow the classification criteria in the grade standards, Table IV. Note that any 

noticeable fiber up to 1 inch is a minor defect; fibers more than 1 inch up to 2 inches is a 

major defect; fibers longer than 2 inches are a severe defect. Woody units of any length 

are severe defects.

A single unit can be scored twice for character defects. For example, a spear may be 

poorly developed and be a major development defect. The same spear may have 

1/2 inch of tough fiber and be a minor fiber defect. In such an instance, the spear would 

be classified as one minor and one major defect under the character factor.

PREREQUISITES 

The following product characteristics and extraneous materials are not readily 

measurable and are not included in the tables of classified defects, but are important in 

the assessment of overall quality:

• Flavor and odor,

• Grit, silt and earthy material,

• Similar varietal characteristics,

• Overall appearance, and 

• Loose material that is measurable by weight.
Inspection Instructions for Frozen Asparagus (September 2015)

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Grades A and B both require that the product has a good flavor and odor; is free of grit, 

silt, or other earthy material; has similar varietal characteristics; and meets a 5% and 

10% limit, respectively, for loose material. To meet Grade A requirements, the product 

must have an attractive appearance; for Grade B, it need be reasonably attractive. 

Good flavor and odor means that the product has the flavor and odor of asparagus 

before and after cooking, and has been properly prepared from freshly harvested 

asparagus, including proper blanching, freezing, and handling in accordance with good 

commercial practice. The product must be free of off-flavors and odors of any kind, 

such as hay-like flavors or odors. If the product has an objectionable flavor or odor 

(e.g., a flavor or odor that would likely cause the consumer to discard the product), it 

should be considered Grade Not Certified (GNC). Instructions and cook times for 

cooking frozen asparagus may be found in the AIM Technical Procedures Manual, 

Cooking Procedures section.

Free from grit, silt, or earthy material means that the product does not contain any of 

this material that is readily visible or noticeable upon chewing. Asparagus is sometimes 

raised on peat soil and if not thoroughly washed, may carry over a little peat. Heavy 

wind may imbed particles of sand in the shoot and under the bracts that is difficult to 

remove. During examination of the sample, check carefully for visual extraneous 

matter. Check the cooked product for presence of grit or sand by chewing suspect 

portions of the product. If, upon visual observation and the chewing test, extraneous 

matter or sand is more than slightly noticeable, the product is classified, e.g., 

Substandard, account grit. If the material is present in extreme quantities and would be 

highly objectionable to the consumer, classify the product as GNC.

Similar varietal characteristics means that the asparagus must be of similar color types, 

although there may be variations within such color types. This requirement is seldom a 

problem. An extreme example of dissimilar varietal characteristics would be a mixture 

of all-green and culturally bleached units.

Overall appearance, which assesses whether the product is attractive or reasonably 

attractive, is a control that can be used to address any unusual characteristic that would 

affect the overall appearance, or make the product undesirable for the indicated grade 

even though the sample would meet all of the objective criteria for classified defects.

LOOSE MATERIAL

Loose material means any shattered material and cut or broken pieces that are less 

than 3/8 inch in length.

Loose material determinations are made on the basis of sample weight and not on a 

standard sample unit of 50 spears (or 100 cut spears). The most practical way to 

handle the requirement is to separate the shattered material and small pieces from each 

container and weigh the material on a gram scale. 
Inspection Instructions for Frozen Asparagus (September 2015)

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An alternative is to collect all the loose material from all of the packages in the sample 

and make only one weighing. This may be done since the requirement is on the basis 

of sample average and not on individual sample units. 

For in-line control, record loose material in order of production if this type of defect is a 

problem. For institutional size packages of cuts, or cuts and tips, take a well-mixed 10-

ounce subsample from each package and base loose material on the total of those 

subsamples.
Inspection Instructions for Frozen Asparagus (September 2015)

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APPENDIX I STAGES OF DEVELOPMENT IN FROZEN ASPARAGUS

Plate 1

1. 2.

Spears show lower limit for Well Developed Heads
Inspection Instructions for Frozen Asparagus (September 2015)

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APPENDIX II STAGES OF DEVELOPMENT IN FROZEN ASPARAGUS

Plate 2

 3. 4. 5. 6.

Spears show lower limit for Reasonably Well Developed Heads
Inspection Instructions for Frozen Asparagus (September 2015)

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APPENDIX III STAGES OF DEVELOPMENT IN FROZEN ASPARAGUS

Plate 3

 7. 8. 9. 10.

Spears show lower limit for Reasonably Well Developed Heads
Inspection Instructions for Frozen Asparagus (September 2015)

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APPENDIX IV TABLE III

TOLERANCES FOR SIZE 

COMPLIANCE

SINGLE SIZES BLENDS OF SIZES

Maximum Defects Permitted

In any Sample Unit

(AL)1 5 10 15 10

Number of 

Sample 

Units

Number of 

Spears or 

Tips

Severe Major Total 2 Minor or Total 3

In the Total Sample In the Total Sample

1 50 3 7 12 7

2 100 5 13 21 13

3 150 7 18 30 18

4 200 9 22 39 22

5 250 10 27 47 27

6 300 12 32 55 32

7 350 14 36 63 36

8 400 15 41 72 41

9 450 17 45 80 45

10 500 18 50 90 50

11 550 20 54 96 54

12 600 21 59 104 59

13 650 23 63 112 63

14 700 24 68 121 68

15 750 26 72 129 72

16 800 27 76 140 76

17 850 29 81 145 81

18 900 30 85 153 85

19 950 32 90 161 90

20 1000 33 94 169 94

21 1050 35 98 177 98

22 1100 36 103 185 103

23 1150 37 107 192 107

24 1200 39 111 200 111

25 1250 41 116 208 116

26 1300 42 120 216 120

27 1350 43 124 224 124

28 1400 45 129 232 129
Inspection Instructions for Frozen Asparagus (September 2015)

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TABLE III Continued

TOLERANCES FOR SIZE 

COMPLIANCE

SINGLE SIZES BLENDS OF SIZES

Maximum Defects Permitted

In any Sample Unit

(AL)1 5 10 15 10

Number of 

Sample 

Units

Number of 

Spears or 

Tips

Severe Major Total 2 Minor or Total 3

In the Total Sample In the Total Sample

29 1450 46 133 240 133

30 1500 47 137 248 137

31 1550 49 142 256 142

32 1600 50 146 264 146

33 1650 52 150 271 150

34 1700 53 154 279 154

35 1750 54 159 287 159

36 1800 56 163 295 163

37 1850 57 167 303 167

38 1900 59 171 311 171

39 1950 60 176 318 176

40 2000 62 180 326 180

41 2050 63 184 334 184

42 2100 64 188 342 188

43 2150 66 193 350 193

44 2200 67 197 358 197

45 2250 68 201 365 201

46 2300 70 205 373 205

47 2350 71 210 381 210

48 2400 72 214 389 214

49 2450 74 218 397 218

50 2500 75 222 404 222

1 In any sample unit, except the first one of 50 Spears or Tips.

2 “Total” – the sum “Severe”, “Major”, and “Minor” defects, as applicable. 3 In “Blends of Sizes”, “Minor” and “Total” defects are the same.
Inspection Instructions for Frozen Asparagus (September 2015)

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APPENDIX V TABLE IV

GRADE COMPLIANCE 

Spears; and Tips

U.S. Grade A U.S. Grade B

Maximum Defects Permitted

In any Sample Unit

(AL)1

0 5 8 15 2 8 13 25

Critical Severe Major Total 2 Critical Severe Major Total 2

1 50 0 3 6 12 1 6 10 20

2 100 0 5 11 21 2 11 18 37

3 150 0 7 15 30 3 15 25 53

4 200 0 9 19 39 3 19 33 68

5 250 0 10 23 47 4 23 40 84

6 300 0 12 27 55 4 27 47 99

7 350 0 14 30 63 5 30 54 114

8 400 0 15 34 72 5 34 61 130

9 450 0 17 38 80 6 38 68 145

10 500 0 18 42 90 6 42 76 159

11 550 0 20 45 96 7 45 81 175

12 600 0 21 49 104 7 49 88 190

13 650 0 23 53 112 8 53 95 204

14 700 0 24 56 121 8 56 102 219

15 750 0 26 60 129 9 60 108 234

16 800 0 27 64 140 9 64 117 249

17 850 0 29 67 145 9 67 122 264

18 900 0 30 71 153 10 71 129 278

19 950 0 32 74 161 10 74 136 293

20 1000 0 33 78 169 11 78 142 308

21 1050 0 35 81 177 11 81 149 322

22 1100 0 36 85 185 12 85 156 333

23 1150 0 37 88 192 12 88 162 347

24 1200 0 39 92 200 12 92 169 362

25 1250 0 41 95 208 13 95 176 376

26 1300 0 42 99 216 13 99 182 391

27 1350 0 43 102 224 14 102 189 405

28 1400 0 45 106 232 14 106 195 420

29 1450 0 46 109 240 15 109 202 434

30 1500 0 47 113 248 15 113 209 449

31 1550 0 49 117 256 15 117 215 463

32 1600 0 50 120 264 16 120 222 478

33 1650 0 52 124 271 16 124 228 492

34 1700 0 53 127 279 17 127 235 506
Inspection Instructions for Frozen Asparagus (September 2015)

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TABLE IV Continued

GRADE COMPLIANCE 

Spears; and Tips

U.S. Grade A U.S. Grade B

Maximum Defects Permitted

In any Sample Unit

(AL)1

0 5 8 15 2 8 13 25

Critical Severe Major Total 2 Critical Severe Major Total 2

35 1750 0 54 131 287 17 131 242 521

36 1800 0 56 134 295 17 134 248 535

37 1850 0 57 138 303 18 138 255 550

38 1900 0 59 141 311 18 141 261 564

39 1950 0 60 145 318 19 145 268 579

40 2000 0 62 148 326 19 148 274 593

41 2050 0 63 152 334 19 152 281 607

42 2100 0 64 155 342 20 155 287 622

43 2150 0 66 159 350 20 159 294 636

44 2200 0 67 162 358 21 162 301 651

45 2250 0 68 166 365 21 166 307 665

46 2300 0 70 169 373 21 169 314 679

47 2350 0 71 172 381 22 172 320 694

48 2400 0 72 176 389 22 176 327 708

49 2450 0 74 179 397 23 179 333 723

50 2500 0 75 183 404 23 183 340 737

1 In any sample unit, except the first one of 50 Spears or Tips.

2 “Total” – the sum “Critical”, “Severe”, “Major”, and “Minor” defects, as applicable.
Inspection Instructions for Frozen Asparagus (September 2015)

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APPENDIX VI TABLE V

GRADE COMPLIANCE

Cut Spears; and Cuts

U.S. Grade A U.S. Grade B

Maximum Defects Permitted

In any Sample Unit (AL)1 0 7 14 25 3 14 22 44

Critical Severe Major Total 2 Critical Severe Major Total 2

1 100 0 5 11 21 2 11 18 37

2 200 0 9 19 39 3 19 33 68

3 300 0 12 27 55 4 27 47 99

4 400 0 15 34 72 5 34 61 130

5 500 0 18 42 90 6 42 76 160

6 600 0 21 49 104 7 49 88 190

7 700 0 24 56 121 8 56 102 219

8 800 0 27 64 140 9 64 117 249

9 900 0 30 71 153 10 71 129 278

10 1000 0 33 78 169 11 78 142 308

11 1100 0 36 85 185 12 85 156 337

12 1200 0 39 92 200 12 92 169 366

13 1300 0 42 99 216 13 99 182 396

14 1400 0 45 106 232 14 106 195 425

15 1500 0 47 113 248 15 113 209 454

16 1600 0 50 120 264 16 120 222 483

17 1700 0 53 127 279 17 127 235 512

18 1800 0 56 134 295 17 134 248 541

19 1900 0 59 141 311 18 141 261 570

20 2000 0 62 148 326 19 148 274 599

21 2100 0 64 155 342 20 155 287 628

22 2200 0 67 162 358 21 162 301 651

23 2300 0 70 169 373 21 169 314 679

24 2400 0 72 176 389 22 176 327 708

25 2500 0 75 183 404 23 183 340 737

26 2600 0 78 190 420 24 190 353 766

27 2700 0 81 197 436 24 197 366 794

28 2800 0 83 203 451 25 203 379 823

29 2900 0 86 210 467 26 210 392 852

30 3000 0 89 217 482 27 217 405 880

31 3100 0 92 224 498 28 224 418 909

32 3200 0 94 231 513 28 231 431 938

33 3300 0 97 238 529 29 238 444 966

34 3400 0 100 245 544 30 245 457 995
Inspection Instructions for Frozen Asparagus (September 2015)

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TABLE IV Continued

1 In any sample unit, except the first one of 100 cuts. 

2 “Total” – the sum “Critical”, “Severe”, “Major”, and “Minor” defects, as applicable.

GRADE COMPLIANCE 

Cut Spears; and Cuts

U.S. Grade A U.S. Grade B

Maximum Defects Permitted

In any Sample Unit (AL)1 0 7 14 25 3 14 22 44

Critical Severe Major Total 2 Critical Severe Major Total 2

35 3500 0 102 252 560 31 252 470 1024

36 3600 0 105 258 575 31 258 483 1052

37 3700 0 108 265 591 32 265 496 1081

38 3800 0 111 272 606 33 272 509 1110

39 3900 0 113 279 622 34 279 521 1138

40 4000 0 116 286 637 34 286 534 1167

41 4100 0 119 292 653 35 292 547 1195

42 4200 0 122 299 668 36 299 560 1224

43 4300 0 124 306 684 37 306 573 1252

44 4400 0 127 313 699 37 313 586 1281

45 4500 0 130 320 714 38 320 599 1310

46 4600 0 132 327 730 39 327 612 1338

47 4700 0 135 333 745 40 333 625 1367

48 4800 0 138 340 761 40 340 638 1395

49 4900 0 140 347 776 41 347 651 1424

50 5000 0 143 354 792 42 354 663 1452
Inspection Instructions for Frozen Asparagus (September 2015)

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APPENDIX VIII – EXAMPLE TALLY SHEET AND CONTROL CHART
Inspection Instructions for Frozen Asparagus (September 2015)

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