United States

Department of

Agriculture

Agricultural

Marketing 

Service

Fruit and Vegetable

Division

Processed Products 

Branch

Grading Manual for

Canned Pumpkin and

Canned Squash

Effective August 1956
Reprinted April 1994

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 permissionof 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 manualdoes notexcuse failure to comply with the

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

regulations.

Exceptfor officialUSDA inspectionaids or devicesand colorguides (orstandards)produced

under license of the Department, the mentionof any supplier, patenteddevice,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
Canned Pumpkin

and Squash

August 1956

i Reprinted April 1994

TABLE OF CONTENTS

Page No.

I. GENERAL. .......................................................... 1

A. Purpose and Scope. ............................................ 1

B. Caution. ....................................................... 1

C. Keep Instructions Current. ........................................ 1

II. PRODUCTION. ....................................................... 1

A. Annual Pack. ................................................... 1

B. Packing Areas. ................................................. 1

C. Varieties. ...................................................... 2

D. Harvesting. .................................................... 2

III. PREPARATION AND CANNING ........................................ 2

A. Receiving. ..................................................... 2

B. Washing. ...................................................... 2

C. Trimming. ..................................................... 3

D. Cutting. ....................................................... 3

E. Wilting (Steaming). .............................................. 3

F. Pressing. ...................................................... 4

G. Pulping. ....................................................... 4

H. Finishing. ...................................................... 4

I. Preheating. .................................................... 5

J. Filling. ........................................................ 5

K. Processing. .................................................... 5

L. Cooling. ....................................................... 6

IV. INSPECTION OF THE PRODUCT ...................................... 6

A. Sampling. ..................................................... 6

B. Inspection Equipment. ........................................... 6

1. Equipment for Grading. .................................... 7

2. Supplies for Grading. ...................................... 7

C. General Inspection Procedure. .................................... 8

D. Setting Up The Score Sheet. ..................................... 8

E. Net Weight. .................................................... 8

F. Fill of Container. ................................................ 8

G. Grade Factors Which Are Not Scored. ............................. 9

1. Normal Flavor and Odor. ................................... 9

H. Grade Factors Which are Scored. ................................. 9

1. Consistency. ............................................. 9

2. Color. ................................................... 10

3. Finish. .................................................. 11

4. Defects. ................................................. 11

I. Proper Evaluation of the Grades. .................................. 12
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and Squash

August 1956

ii Reprinted April 1994

Page No.

V. CERTIFICATION ..................................................... 12

A. General Instructions. ............................................. 12

B. Special Instructions. ............................................. 12

1. Name of the Product Inspected. ............................. 12

2. Requests for Specific Certificate Information. ................. 13

VI. INSPECTION DURING PACKING OPERATIONS .......................... 13

A. Sanitation. ..................................................... 13

B. Operations. .................................................... 13

1. Raw Material. ............................................ 13

2. Preparation and Workmanship. ............................. 14

3. Processing. .............................................. 16

4. Starch Pockets. .......................................... 16

C. Recommendations. ............................................. 16
Canned Pumpkin

and Squash

August 1956

1 Reprinted April 1994

I. GENERAL.

 

A. Purpose and Scope.

The instructions contained herein explain and furnish technical information

which will serve as a guide in the inspection of canned pumpkin and canned

squash and will aid inspectors in attaining uniformity in applying the United

States grade standards and in the proper certification of the product. These

instructions will also serve to familiarize the inspectors with the commercial

product of canned pumpkin and the general procedure used by the industry.

B. Caution.

Inspectors are reminded thatthese are administrative instructions for theiruse

only and not for public distribution.

C. Keep Instructions Current.

These instructions may be revised, in whole or in part, whenever the need for

such revision is indicated. Therefore, any comments or suggestions such as

detectionof errors or the development of newand better inspectiontechniques

should be forwarded in detail to the Washington office.

II. PRODUCTION.

A. Annual Pack.

The quantity of canned pumpkin and squash in 1952 exceeded 4,000,000

actual cases, ranking eighth among vegetables for canning. The average

yearly pack is normally around 2,000,000 actual cases.

B. Packing Areas.

The principal producing areas of canned pumpkin and squash are Illinois,

Indiana, New York, Maine, Minnesota, California, Washington, and Oregon.
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C. Varieties.

The names pumpkin and squash are propularly applied to the fruits of the

speciesofthe genus Cucurbita,namely C pepo,C maxima and C moschata. In

general, the term pumpkin is applied to the late maturing or fall varieties of C

pepo and C maxima. The principal varieties of C pepo and C. maxima used

for canning are the Connecticut field pumpkin, Dickinson pumpkin, Kentucky

field pumpkin, the Boston marrow squash, and the Golden Delicious squash.

D. Harvesting.

Pumpkin and squash should not be harvested for canning until fully

matured. Harvesting is usually done after the leaves begin to turn yellow.

Mature pumpkin or squash have a hard rind which can be dented only with

difficulty with the thumbnail. If picked too green the under portions of the

pumpkin will have a greenish color and this may be carried over into the

finished product. Pumpkin and squash are usually harvested starting

approximately September 15 in the Midwest and Northeast States, and

October 1 in the Pacific Northwest.

III. PREPARATION AND CANNING.

A. Receiving.

Pumpkin and squash are usually delivered as harvested and stored at the

cannery until used. Well-matured pumpkin or squash will keep for several

weeks if stored in a well-ventilated place. In some areas it may be necessary

to store them in an enclosed shed for protectionagainst freezing. Normally no

inspection is made of pumpkin or squash received by the plants.

B. Washing.

Whole pumpkins or squashes are fed by hand or conveyed into a combined

tank and spraywasher,consisting of a rotarydrum partially submerged in atank

of water. The combined soaking and rotary motion loosens adhering dirt which

is removed by strong sprays of water. Grit sometimes becomes embedded in

the rind, necessitating thorough washing.
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C. Trimming.

From the washer the pumpkins or squashes pass to the inspection belt where

stems are knocked off by hand and blossom ends, scar tissue rot, and other

blemishes are trimmed out.

D. Cutting.

In some canneries the trimmers also cut the pumpkin or squash into halves or

quarters with long knives and scrape out the seeds and stringypulp byhand. In

many plants mechanical cutters are used into which the whole units (or halves)

are fed by conveyor cutting the units in pieces. Strong sprays ofwater help to

knock out most of the seeds, which drop from the cutter through small

perforations.

Where the units are cut and the seeds and pulp removed in separate

operations, the cut pieces pass to a revolving drum where they are tumbled

under strong sprays of water which remove most of the seeds and pulp.

Where seeds are to be saved for planting, they may undergo further washing

to separate them from the pulp.

Cut pieces are in some cases passed over aninspectionbelt where imperfect

pieces and internalrot, not visible from the outside,maybe picked out byhand.

E. Wilting (Steaming).

The cut pieces are cooked in live steam until they are tender all the way

through. The length of time necessary depends upon the size of the pieces and

the nature of the equipment in which the steaming is done. The following are

examples in which the wilting or steaming may be accomplished:

1. In metal baskets in retorts, either under pressure or at atmospheric

pressure.

2. In continuous metal box wilters. The pieces are carried through on a

continuous belt and are subjected to live steam.
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3. In wilting towers. These are tall cylindrical silo-like structures into which

the cut pieces are fed continuously at the top by conveyor and removed

at the bottom by a screw conveyor. The pumpkin or squash is

continuously treated with live steam as it passes through the wilting

tower.

F. Pressing.

The wilted pumpkin or squash is soggy with liquid which is a mixture of

condensed steam and pumpkin or squash juice. The product is treated to

remove excess liquid in order to attain the desired consistency in the canned

product. This is done by putting the wilted pumpkin or squash through an

adjustable press. In certain plants the pressing and wilting is done

simultaneously by the use ofaugersinsideof cone-shaped perforated screens.

G. Pulping.

The pressed pumpkin or squash goes to the pulper or cyclone to remove hard

particles, pieces of stems, seeds,fiber,and otherextraneous material. In some

cases the product is firstputthroughacoarse,heavy cyclone to remove the bulk

of extraneous material and an ordinary cyclone to reduce the size of the

particles. For the latter a screen with perforations 1/8 inch in diameter is

commonly used.

Some processors use whatis commercially knownas a Fitzmill. This machine

constructed with hammer and knive edges onopposite sides reduces or pulps

pumpkin by a combined impact mashing action.

H. Finishing.

From the pulper the product goes to the finisher which removes the finer bits of

seeds or other material and gives the final product the desired physical

character. There is a difference of opinion among canners as to the most

desirable size of the particles of pumpkinin the finished product. Some prefer

a very smooth product which can be obtained by using a very fine finisher;

othersfeelthatthe cannedpumpkinor squashshould have a noticeable amount

of grainy structure and, therefore, use a finisher that is relatively coarse.
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I. Preheating.

The filling temperature of the prepared pumpkinor squash is an important part

of processing. Heat penetration of the product is very slow because of its

physical character, and the temperature at the beginning of the process is

correspondingly important. By use of the preheater, it is possible to fill all of the

cans at a uniform high temperature.

The preheater is usually a straight piece of pipe surrounded by a larger

pipe. The product is pumped through the smaller internal pipe and the space

between the two pipes is filled with steam, the temperature of which can be

controlled. The rate of flowof the product throughthe pipe and the temperature

of the steam determines the temperature at which it goes to the filler. The

preheater normally raises the temperature of the product to 190-200 degrees

F. To prevent scorching the preheater is usually constructed so that it will shut

off automatically if, for any reason, the flow through the inside pipe is stopped.

J. Filling.

The hot pumpkin or squash goes directly to the filler and into cans. If the

thickness of the product at this point is too great, the product may not be

handled properly by the filler. If, for any reason, the filler or closing machine is

forced to stop for any length of time all of the pumpkin material should be put

back with the material going though the preheater.

Pumpkin or squash has a corrosive action on tin-plate and should be packed

in enamel lined cans. It is important to fill the cans completely so that the

product is in contact with the entire inner surface of the cover when the can is

sealed. Even a small headspace may result in some discoloration after

processing.

K. Processing.

The filled cans should be processed promptly. High closing temperature may

be off-set by undue delay between closing and starting of the process time. A

partially filled crate of cans should be sent at once to the retort rather than

awaiting any time for additional cans.
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L. Cooling.

Prompt and adequate cooling is especially important since canned pumpkin

has a slow heating and cooling rate. Failure to cool the product promptly may

result in over cooking and loss of color and may be directly responsible for

spoilage by thermophilic bacteria.

Cooling is usually accomplished by moving the metal retort baskets through a

long tank of water by means of an overhead endless chain. The speed of the

chain is regulated according to the degree of cooling desired. Cold water is

kept continuously flowing into the tank to hold down the

temperature. Immediately after cooking, while the cans are distended byheat

and internal pressure, minute openings in the double seams may be

present. Cooling water contaminated with bacteria may be drawn through

seamopeningsaspressureinthe cans is replaced by vacuum; therefore,water

in the cooling tank should be kept clean. Some canners cool by means of a

water spray in order to reduce the contamination hazard.

IV. INSPECTION OF THE PRODUCT.

A. Sampling.

It is equally as important to draw representative samples as it is to accurately

examine and classify the samples as to quality. Make sure that the best

possible sampling job has beendone so that the samples will represent the lot

which is being inspected. The sampling rates prescribed in the Rules and

Regulations and in other Inspectors' Instructions and Memorandums should be

followed when drawing samples for the inspection of canned pumpkin or

squash. Pertinent information with respect to the product should be recorded

onthe sampling certificate, such as condition of containers, cases, locationof

the lot, and all means of identification in the event that it will be necessary to

supervise the loading of the lot.

B. Inspection Equipment.

The following lists comprise the minimum equipment and supplies needed for

inspection of canned pumpkin or squash:
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1. Equipment for Grading.

a. Grading scale - 1/4 ounce graduations.

b. Vacuum gauge.

c. Can opener.

d. Beer can opener.

e. Trays - white, shallow (about 10" x 14").

f. Trays - white, deep (about 10" x 14").

g. Plastic ruler.

` 2. Supplies for Grading.

a. Folder containing:

(1) United States grade standards and the Federal

specifications for canned pumpkin and canned squash.

(2) Grading Manual for Canned Pumpkin and Canned

Squash and any supplemental instructions.

(3) Sampling sheets.

(4) Score sheets.

(5) Towels.

(6) Marking pen.

(7) Sampling stamp.
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C. General Inspection Procedure.

The United States Standards for Grades of Canned Pumpkin and Canned

Squash describe and establish requirements for the quality factors as

accurately as it has been possible to do. In order to uniformly apply the

standards, however, it is necessary for each inspector to be guided by their

supervisor when there is any doubt as to the correct interpretation of any

requirement. This is particularly important whenever unusual conditions are

encountered or whenanerror in the interpretation of a requirement will change

the product from one grade to another. Quality requirements which involve

judgement as to the extent to which the appearance and eating quality are

affected should always be checked with your supervisor, unless you are sure

youare applying the proper interpretation. Supervisors should make sure their

judgement is in line with Regional supervisor's and the Washington office.

D. Setting Up The Score Sheet.

Record all important informationconcerning the inspection on the score sheet

in addition to the packer's name, date, and inspector's signature; this also

includes suchinformationas netweights,size and kind of containers, vacuums,

packer's codenumbersormarksthatare present, and allsignificantinformation

taken from the labels.

E. Net Weight.

The net weight of the product means the weight of the pumpkin or squash less

the weight of the container. Record the net weight for each container.

F. Fill of Container.

Prior to observing the fill of container, vacuum readings should be

taken. Normally there is very little headspace found in canned pumpkin or

canned squashsince evenasmallheadspacemayresult in some discoloration

after processing. When it appears that the headspace is excessive or close to

the 10 percent of the volume of the container, the headspace should be

measured with the headspace gauge.
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G. Grade Factors Which Are Not Scored.

1. Normal Flavor and Odor.

Normal flavor and odor is required in each grade above

Substandard. The percent total solids and variety may cause flavor

variations but only objectionable flavor are important. When the canned

pumpkinor canned squashdefinitelypossessesanobjectionable flavor

orodor suchas scorched or bitter taste,the product should be classified

as Substandard.

H. Grade Factors Which are Scored.

1. Consistency.

The factor of consistencyshould be scored immediately after emptying

the product from the container. Prior to emptying the product from the

container the temperature should approximate 68 degrees

Fahrenheit. To empty the product from the container completely remove

one end of the container, placing the opened end down ona flatsurface,

using a beer canopener or vacuum gauge puncture severalholes in the

unopened end to release the vacuum present and verticallyslidethe can

cylinder off the product.

Do not touch or adjust the settling of the product. At the end of two

minutes measure the highest point of the mound to the flatsurface of the

tray. A thin plastic ruler may be used for this purpose. To measure the

free liquor that separates from the product, tilt the tray slightly and pour

or lift by pipette the liquor which separates.

The requirements for good consistency are outlined in the grade

standards and it should not be necessary to repeat them here.

Canned pumpkin or squash to meet the requirement of fairly good

consistency when emptied from the container should not level off

completely intwo minutes and notmore than 30 cc of free liquor should

separate from the product for each 30 ounces of net contents.
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2. Color.

The colorofthe product may varyconsiderably because of the various methods

of processing and maturity. In rating this factor keep in mind (1) uniformity; (2)

brightness, and (3) is the color typicalof a well matured pumpkin or squash for

the variety. Immature pumpkin or squash, overcooking or other improper

processing, such as stackburn, may cause poor color. To score in the Grade

A classification the canned pumpkin or canned squash should have a uniform

bright color. Lots may differ in color provided they are typical of a product

prepared from well matured pumpkin or squash.

Cannedpumpkinorsquashwhichhas agreenish-yelloworgreenish-orangetint

typical of squash not fully matured or is dull, slightly tan or slightly gray in color

should be scored as meeting the requirements of fairly good color. Canned

pumpkin or canned squash that fails the requirements for fairly good color

should be scored Substandard.
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May 1959

10a Reprinted April 1994

a. Explanation of Plastic USDA Color Guides.

Inspectors are cautioned that these color guides are minimum

color allowed in each color classification and these guides will

not always match the more intense, rich colors of canned

pumpkin.

(1) USDA Color Guide No. 1 (Fancy Color) illustrates the

minimum color which would be considered Canned

Pumpkin or Canned Squash prepared from well

matured pumpkin or squash.

To score in the "A" classification for color the canned

product must possess a practically uniform bright color

typical of canned pumpkin or canned squash prepared

from well matured pumpkin or squash.

Color No. 1 illustrates the minimum orange color allowed

(or bottom limit) in the "A" color classification. When the

sample is bright in color and is equal to or better (as

much or more orange and less green) than USDA color

Model No. 1 the product should be scored in the "A"

classificationfor color. Color alone is nota limiting rule in

the "A" classification.

(2) USDA Color Guide No. 2 (Standard Color) illustrates

the minimum color which would be considered Canned

Pumpkin or Canned Squash prepared from fairly well

matured pumpkin or squash.

To score in the "C" classification for color the canned

product must possess a colortypicalof fairly well matured

pumpkin or squash and may possess a slight tinge of

grayor tancolor, maybe variable or slightly dull but not to

the extent that the appearance or eating quality is

materially affected.

Color No. 2 illustrates the minimum orange color (or

bottom limit) which would be allowed in the "C"

classification. When the sample is no more than slightly

dull in color and is equal to or better (as much or more

orangeand lessgreen) thanUSDA color ModelNo.2, the

product should be scored in the "C" classification for

color.

(3) Samples that are dull in color and are not as good in 
Canned Pumpkin and Squash

May 1959

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color (less orange and more green) as No. 2 are

classified as Substandard in color.

(4) How to Use the USDA Color Guide for Canned

Pumpkin and Canned Squash.

(a) Pour a mound of the canned pumpkin or canned

squash on a flat tray. The mound should be thick

enough so that no light is reflected through the

product from the bottom of the tray.

(b) Place the color guide on the canned pumpkin or

canned squash, shiny side up, and push down so

that the surface of the product and the guide are

about on the same plane.

(c) To eliminate texture, place a piece of colorless

clear plastic or glass beside the color guide in a

manner so that approximately the same area of

the guide and the productunderthe plastic maybe

observed side by side and under the same

conditions.

(d) Make the observationunder the best conditions of

lighting that are available, preferable under

constant laboratory lighting that approximates

diffused north daylight (about 7500 degrees

Kelvin).

(5) Direction for Care of Color Guides.

The color guides -- No.1 and No. 2 -- are made of plastic

and should be handled carefully to avoid scratching. The

color guides should be cleansed immediately after using

with water and a mild soap. The surfaces maybe further

cleaned and dried with a soft cloth. No abrasive cleaner

should be used. It is suggested that they be replaced in

the protective envelope and be stored in the box that is

furnished with each set of color comparators. They

should be covered and stored in a cool dark place when

not on display or in actual use.

(6) One set of plastic color comparators (No. 1 and No.2) is

located at each Processed Products Inspection Office.

3. Finish.

To determine the finish, smooth a portion of the product with a spatula

or knife to see that a smooth surface results. Observe the fineness of

the particles and freedom from hard or lumpy pieces. To meet the

requirements ofgood finish the pumpkinor squashparticles should be

evenly divided, fine grained, smooth but not pasty, and the pumpkin or

squash particles are tender.

Canned pumpkinor squashof whichthe particles are slightly coarse or
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August 1956

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slightly pasty should be scored as meeting only fairly good finish.

A product which is definitely pasty or the particles are definitely hard or

definitely coarse should score in the Substandard range for the factor.

4. Defects.

The determination of the score for defects should be made after the

contents have beenevenly spread ona flat white grading trayor a sheet

of white paper. The most common defects consist of particles of seed,

dark or off-colored particles, and grit, sand or silt. The number, size,

color, and type of such defects should be taken into consideration in

scoring theireffect onthe appearance and eating qualityof the product.

If the appearance and eating quality of the product is not materially

affected by the presence of defects, it should be scored as practically

free from defects. In this connection a few rather large dark or

off-colored particles might affect the appearance more than several

times that number of small, lighter colored particles.

Canned pumpkin or squash in which the defects are decidedly

noticeable but notto the extent thattheyseriously affect the appearance

or eating quality should be scored as meeting the requirement of fairly

free from defects.

The degree of freedom from sand, grit, or silt should be determined by

chewing several spoonfuls of the product and noting the presence or

absence as it affects the eating quality.
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Canned pumpkin or squash shall be considered as containing no grit,

if, upon chewing representative portionof the product, no grit or sand is

detected. In other words, grit should not be detected in the product when

subjected to normal eating or chewing tests.

Canned pumpkin or squash shall be considered as containing a trace

of grit, if, upon chewing a representative portion of the product, grit or

sand is detectable in occasional mouthfuls but not to the extent of

materially impairing the eating quality. If grit or sand is present in

amounts so as to be frequently detected upon chewing, the eating

quality is materially affected and the product should be considered as

containing more than a trace of grit.

The supervisor should be consulted when in doubt with respect to the

classification for defects.

I. Proper Evaluation of the Grades.

After the inspector has properly applied the detailed requirements of the grade

standards, it is necessary before certifying the grade of the product to assure

themselves thatthe overall appearanceand eating qualityofthe productreflects

the grade that the standards have intended. If the inspector feels the grade

standards do not properly reflect the proper quality level they should consult

their supervisor.

V. CERTIFICATION

A. General Instructions.

General instructions pertaining to certification of all processed food products

are applicable to this product.

B. Special Instructions.

1. Name of the Product Inspected.

The inspector should use the name of the product on the label or if not

labeled the name declared by the applicant. It will be the policy of the

Inspection Service to certify the name of the product without question

as either squash or pumpkin on the basis of applicant's declaration.
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2. Requests for Specific Certificate Information.

Certainpurchasers of this product have setup specific requirements in

their purchase specifications, sometimes based on the United States

standards. For example, such purchase specifications might require a

GradeA product and also a minimum score of27pointsforconsistency.

Procedure. If specifically requested, show such special information in

the body of the certificate as:

Consistency score - 27 to 29 points.

The grade statement may also show compliance (or noncompliance)

with a specific purchase specification in the manner outlined in general

instructions on the subject of certification.

VI. INSPECTION DURING PACKING OPERATIONS

A. Sanitation.

It is the duty of the inspector assigned to a plant to see thatgood standards of

sanitationare maintained. There is a very rapid build-up of scum and starch on

belts, flumes, and other partsofthe machinery, causing notonly offensive odors

in the plant but mycause off-odor, off-flavor, and spoilage inthe product. These

conditions can be controlled by careful periodic cleaning of all pieces of

equipment.

B. Operations.

Following are particular points to observe during the processing

operation. They supplement general instructions or emphasize particular points

to observe:

1. Raw Material.

a. Observe the condition of the pumpkinor squashat the time they

arrive at the plant.

b. The length of time the raw product is held before processing

should be noted.

c. Prevalence of defective pumpkin or squash -

(1) Presence of excessive dirt, sand, or silt.

(2) Presence of damaged or bruised pumpkin or squash.

(3) Presence of rot, mold, and other decay.

d. Presence of green and overmature pumpkin or squash.

The colorsseenin the freshfleshof pumpkinand squashare due
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to two groups of pigment substances; the carotenoids, whichare

yellow or orange-yellow and the chlorophylls, which are

green. The different varieties show very great differences in the

amounts of the two groups of pigments. Generally there is a

deepening and intensificationof the yellowororange-yellowcolor

as a result of the steaming of the product while the green color

may change to a greenish-brown or reddish-brown color due to

the decomposition of the chlorophyll. Upon cooking there is an

apparent brightening of the colors in pumpkin or squash. 

Pumpkins or squashes should be allowed to ripen in the field. If

picked too green the under portions of the skin will have a

greenish color and this may be carried over into the finished

product. Certain green varieties, for instance the green Hubbard,

are not suitable for canning purposes because of the excessive

amount of this greenish tissue that persists even to the full

matured squash.

e. Presence of infestation, such as flies, gnats, or other insects.

2. Preparation and Workmanship.

a. Check effectiveness of removing defective, green pumpkin or

squash, and stems.

b. Check effectiveness of washing process in removing dirt, silt,

and loose extraneous material.

c. Check cleanliness of wilter screenperiodically, therebyassuring

good drainage.
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d. Check consistency of the pumpkin at periodic intervals.

There are severalfactors whichaffect the consistencyof canned

pumpkin or canned squash. Some of these are the variety or

varieties used, the maturity, time between delivery of the raw

product at the plant and wilting and pressing and the extent of

wilting and pressing. Starch appears to be most abundant just

before the full ripe stage, and it appears desirable to use the

pumpkinor squashat this stage for best consistency. The starch

content of pumpkinor squashreduces sharply after the pumpkin

or squash is taken from the vine, and every day in the cannery

yards is therefore detrimental to the final consistency as well as

to other quality factors. Since it is not always feasible to control

the delivery, ripeness, and storage of the raw material,

processors may increase the degree of pressing to the desired

results. Some wilting systems introduce an undue large quantity

of condensed steam into the pumpkin or squash, thereby

reducing the consistency by thinning. Experienced processors

are able to regulate the consistency very closely.

e. Check efficiency of finishers periodically.

The finish of canned pumpkin and canned squashis affected by

the varieties, maturities of the pumpkin or squash, the time and

temperature of the cooking process. It is also affected by the

size of the openings in the finishing screen. The finish is called

pasty when the granular structure has beendestroyed. A pasty

finish may result from too immature or too ripe pumpkin or

squash, overcooking,or the use of screens in the finisherthatare

too fine. Screens with perforations of 0.040 openings are

generally used in the finisher and will result in a fine

grain. Waste from the finisher should not be of a stiff or dry

consistency. If this condition exists inspectors should watch for

defects caused by pressing too muchmaterialthrough screens.

f. Check presence of defects, such as sand, grit, or silt, pieces of

seed, fiber, and from dark or off-colored particles.

The freedom from defects depends largely on the quality of the

pumpkin or squash used, the efficiency of the washing and

trimming operations, and the care exercised on the final

inspection belt.

g. At frequent intervals, check fill and closing temperature of cans.

3. Processing.

The time and temperature of processing has a directeffectonthe quality

of the finished product and the procedure should be observed

regularly. In this connection, however, make no recommendation unless

it is obvious thatthe standardsestablishedbythe managementfor these

factors are not being maintained.
Canned Pumpkin and Squash

August 1956

16 Reprinted April 1994

4. Starch Pockets.

In filling extra drypumpkinor squashinto cans,airpocketsarefrequently

left. On processing, these air pockets fill with liquid from the pumpkin or

squashwhichcarries with it starchin solution. On cooling the cans after

processing this starchsolution solidifies and forms a white mass which

fills these pockets. Some have thought that this white material was

added starch. It is a starch material but came from the high starch

content of the pumpkin or squash itself. It is, therefore, entirely normal

to a heavy bodied pumpkin.

Because pumpkin and squash normally have substantive amounts of

naturalstarch, there is no necessity for added starchin a product thatis

properly processed under good commercialpractice. Therefore added

starch or added starchand water are considered adulterants under the

general provision of the Federal Food, Drug and Cosmetic Act.

C. Recommendations.

When any abnormal or unsatisfactory condition is observed in either the

sanitation, operation, or processing, it should be brought to attention of the

management though a proper, previously designated, official. Written reports

of unsatisfactoryconditions should bemadeto the plantmanagementwhenever

itappearsnecessary. Suggestions and carefully thought-out recommendations

should be made for overcoming objectionable conditions and improving plant

operations. The inspector should keep the supervisor informed and whenever

serious problems arise, they should consult their supervisor for advice. The

inspector must be alert, tactful,and diplomaticatalltimes. They must also keep

in mind that they are assigned to render a helpful service and have no

regulatory authority.