in GLASS/JARS

UNITED STATES DEPARTMENT OF AGRICULTURE

PRODUCTION AND MARKETIHG ADMINISTRATION

Washington, D.C.

July 1952

AGRICULTURE HANDBOOK N0.44
CANNING IN GLASS JARS ]

IN COMMUNITY CANNING CENTERS

AORICULTrRE HANDBOOK NO. 44

i

UNITED STATES DEPARTMENT OF AGRICULTURE

Production and Marketing Administration
CaBîTENTS

Acknowledgments iv

Introduction : 1

Equipment for canning in glass jars 1

Retorts l

Retort crates 3

Air compressor 3

Automatic control valves 4

External cooling sprays 4

Atmospheric cookers j ,5

Other equipment and facilities ' 5

Partial list of suppliers of canning equipment 6

Location and installation of equipment 7

Retorts 7

Automatic control valves 11

Air compressor 12

Atmospheric cooker 12

External cooling sprays 13

Some key points on equipment maintenance 14

Procedure for operating the equipment 15

Operating retort when processing under pressure 15

Operating retort when cooling under pressure 17

Cooling under external sprays 17

Operating atmospheric cooker 17

Operating retort at 212° to 216° F __j 18

Glass jars and closures 19

Processing time and temperature requirements 22

Procedure for canning acid foods 23

Procedure for canning low-acid vegetables ^ 25

Procedure for canning meat and poultry 27

Issued July 1962

For sale by the Superintendent of Documents, U. S. Government Printing Office

Washington 25, D. C.—Price 20 cents
ACKIVOiri.EDGMEBíTS

Acknowledgment for assistance in the preparation of this pubhcation is made to the following:

Dr. John J. Powers, Head, Department of Food Technology, University of Georgia; Dr. William B.

Esselen, research professor. Department of Food Technology, University of Massachusetts; Dr. Howard

Reynolds, bacteriologist. Food and Nutrition Division, Bureau of Human Nutrition and Home Economics,

United States Department of Agriculture; and James M. Reed, National Canners Association Research

Laboratories, Washington, D. C, for calculating processing times and for helpful suggestions in adapting

home and commercial canning processes to community cannery conditions. Dr. Powers also made available results of studies on processing acid and low-acid foods in glass jars in community-size equipment.

Credit is due Dr. J. Russell Esty and Charles T. Townsend of the National Canners Association Research

Laboratories, Berkeley, Calif., for recommendations on which processing times for acid foods were based.

R. H. Driftmier, chairman. Division of Agricultural Engineering, Harold D. White, research professor of

agricultural engineering, and R. J. McCraney, assistant agricultural engineer. College Experiment Station,

University of Georgia Agricultural Experiment Station, for the preparation of drawings and engineering data

on the installation of the equipment and for assisting in the preparation of instructions on operation of the

equipment; A. O. Duncan, associate professor, Agricultural Education Department, College of Education,

University of Georgia, and A. G. BuUard, subject-matter specialist, Department of Agricultural Education,

North Carolina State College, for making suggestions on organization and presentation; Karl Ford, Ball

Brothers Company, Muncie, Ind., originator of the method described for canning in standard mason jars

in community-size equipment, for furnishing photographs and making helpful suggestions; and Dr. M. B.

Matlack, food technologist, of the Food Distribution Branch, for technical advice on the text.

In printing the partial list of suppliers of canning equipment on page 6, no guaranty of reliability is

implied and no discrimination is intended.
CANNING IN GLASS JARS

IN COMMUNITY CANNING CENTERS

By BERTHA F. OLSEN and ESTHER H. SCOTT, Food Distribution Branch,

Production and Marketing Administration

INTRODIJCTIOBÍ

This publication describes some of the new equipment used in community canning centers to process

food in standard mason jars. It gives detailed information on the installation and operation of the

retorts for steam-processing and pressure-cooling

low-acid foods and on atmospheric cookers for

steam-processing acid foods. Included also are processing times that have been calculated expressly

for the equipment and procedures described. The

publication was designed to provide information on

canning in glass jars as a supplement to Miscellaneous Publication 544, Community Canning

Centers, which deals with canning in tin containers.

Therefore, to avoid repetition, only brief instructions

are given here for preparation of foods for canning.

For more detailed instructions M.P. 544 rhay be

consulted.

In the preparation of this publication advice and

assistance were obtained from leading food technologists and agricultural engineers of the Federal

Government, industry, and State universities. Their

recommendations, with the most recent published

data available on canning in standard mason jars,

under the conditions described in the text, provided

the basis for the instructions given here

EQUIPMENT FOR CANNING IN GLASS JARS

Retorts

Instructions in this publication are based on the

use of vertical single-crate retorts of a certain type

and size (fig. 1). Although these retorts are designed primarily for processing low-acid foods in

glass jars, they may also be used for processing in

tin containers. They will hold 100 quart jars, 195

pint jars, 185 No. 2 cans, 114 No. 3 cans, or 40 No.

10 cans. Except for the way in which the Hd is

secured to the retort shell, these retorts are similar

in construction. Each is equipped as follows:

1. A thermometer with a temperature range of

120° to 270° F. to measure the retort temperature

during cooUng as well as processing. The thermometer, an angle type for easy reading, is installed

near the bottgm below the retort crate. Installed

in this manner, the bulb, which extends into the

retort shell, is given the necessary protection and is

exposed to the steam or water so as to give good

average readings of the retort temperature.

2. A pressure gage with a range of from 0 to 30

pounds per square inch speciñcally designed for steam.

3. A %^-inch pop safety valve set at 15 pounds

gage pressure.

4. Water sprays {4 No. 1 spray nozzles) on the

inside of the retort lid for the initial cooling of the

jars at the end of the process (fig. 14).

5. Water valves, connecting pipes, and a one-half

inch rubber hose to bring the water supply to the

retort. The hose is made to withstand both heat

and pressure. In the pipe connection is a fine

strainer.

6. Air and steam connections are provided near

the top of the retort. The high-pressure steam for

venting and the low-pressure steam for processing

are brought into the retort through separate connections.

7. A 1-inch drain is provided to make sure of

rapid venting and for draining the retort of cooling

water. Venting is done through the drain at the

bottom of the retort when steam is brought in at the

top.
Figuro 1.—Kotorts oqiiippo«! for processing glass jars in

Steam. The retort above has locking arms and a

wheel for tightening the lid to the retort shell.

The retort at the right has wing nuts.
Retort Crates Air Compressor

Figure 2 shows two types of retort crates that are

used for processing in glass jars. The expanded

metal crate, designed especially for the purpose,

insures good circulation of steam. A slatted metal

crate, like those used in community canning centers

for processing in tin containers, is also satisfactory

if the perforated metal bottom is replaced with

expanded metal as shown. The sides of the crate

will also need to be lined with expanded metal

if the slats are too far apart to support the jars.

Compressed air is used to maintain pressure in the

retort at the beginning of the cooling operation.

The air is supplied by a heavy-duty type air compressor with a 30-gallon storage tank (fig. 3). The

storage tank is constructed in accordance with the

code of the American Society of Mechanical Engi -

neers. It is equipped with an automatic pressure

switch, a pressure gage, a pressure-rehef valve, and a

valve for draining the tank. The unit may be

bought with or without a motor, but it is desirable to

buy it complete with motor. If bought without the

motor it is important that the motor used with the

compressor be suitable for the purpose. Any

compressor similar to the one shown in figure 3,

having a capacity of 4 to 5 cubic feet per minute, is

adequate for a canning plant with one to six retorts.

Figure .3.—Air compressor.

Figure 2.—Retort crates: A, Expanded metal; B,

slatted metal crate with expanded metal bottom.
Automatic Control Valves

For Steam

An automatic control valve on the steam line is

essential for maintaining a constant temperature in

the retort during processing. Two of the most

»-AIR SUPPLY

TO LOW PRESSURE STEAM '

HEADERADJUSTING'

SCREW

Figure 4.—Automatic control valves; A, Air-actuated temperature control; ß, back-pressure pilot-operated

pressure control.

reliable types for the purpose are shown in figure 4.

The air-actuated temperature controller (fig. 4^)

is the preferred type. It is extremely sensitive to

temperature changes within the retort or steam

header and will give good service over a long period

of time. The back-pressure pilot-operated automatic-control valve (fig. 4J5) is the most satisfactory

pressure control valve. Community canneries use

this type of valve to a greater extent than the temperature control valve because it is less expensive.

Either type of valve is suitable for use on a steam

header to a battery of retorts or on a single retort.

On a battery set-up, a ^-inch valve is needed; on a

single retort, a p/g-inch valve.

Although the valves shown in figure 4 are the only

types which are satisfactory for a header installation,

there are other self-operated or spring-type valves

that can be used on individual retorts. To make

sure of getting the right type of valve when ordering, specify:

1. That it is to be used for steam.

2. Size required.

3. Operating pressures (boiler and retort).

4. Temperature or pressure to be maintained in

the retort.

5. Accuracy. (The valve should maintain the

desired temperature, within plus or minus 1° F., as

Ions; as the minimum steam pressure specified by the

manufacturer is maintained in the line.)

For Air

An air-control valve is necessary to maintain the

correct air pressure in the retort during the initial

cooling period. A 3^-inch valve, set about 2

pounds higher than the pressure at which processing

is done in the retort, is recommended. Any goodquality valve designed for use with air pressure and

having an accuracy of plus or minus 1 pound at any

setting is satisfactory.

External Cooling Sprays

External cooling sprays are used to cool glass

jars after they are removed from the retort or

atmospheric cooker. The external-spray system

may be bought as a unit (fig. 16, p. 17) or it may be

assembled from parts bought separately. Two

nozzles are needed for each unit—a No. 1, which

delivers 0.2 gallon of water per minute, and a No.

5, which delivers 0.8 gallon per minute, with water

pressure at 30 pounds. Both nozzles produce solid

cone-shaped sprays. The No. 1 nozzle is the same

size as the nozzles in the retort lid. It is used at the

beginning of the cooHng operation, when a fine spray

is needed to avoid breakage of the glass jars. The

No. 5 nozzle is used in the final coohng. As the

cores in these nozzles are easily lost or damaged

during cleaning, extra ones should always be kept

on hand. An average of 1- to 13/2-spray units is

usually provided per retort or atmospheric cooker.
Atmospheric Cookers

The atmospheric cooker was designed for processing acid foods in glass jars, but it may also be used

for processing such products in tin containers. A

simple device, it consists of a bell cover with thermometer, a base pan with overflow drain and crate

support, and an expanded metal crate for holding

the containers. The atmospheric cooker is equipped

to process in steam at 212° F. at sea level. The

steam is admitted at the top of the cover through a

high-pressure steam hose. These cookers come in

two sizes—No. 2 and No. 3. The No. 2 cooker

shown in figure 5 has an approximate capacity of

36 quart jars, 80 pint jars, 64 No. 2 cans, or 36 No.

3 cans. It is convenient to use since the loaded

crate can be placed on the crate support without

using a hoist. The No. 3 cooker, comparable in

size to the retorts desribed on page 1, requires a

hoist to lift both the cover and the loaded crate.

Figure S.-^Base pan, expanded metal crate, and bell cover of No. 2 atmospheric cooker.

Other Equipment and Faeilities

Other equipment and facilities needed for handling

glass jars include the following:

Jar Trays

A simple tray for handling glass jars at the canning

center may be easily constructed (fig. 6). The

frame is made of wood with handholes at either end.

The bottom is of expanded metal. The tray, measuring 93^ by 15 inches on the inside, is large enough to

hold 12 quart jars. Each worker needs two or

three trays to hold the jars while filling them, as

well as for transferring them from one work area

to another. A small truck, with the top at about

the same level as the work tables, is handy for

transferring trays of filled jars from the filling table

to the loading table.

212370—52 2

Figure 6.—Jar trays.
Loading Table

A sturdy table (fig. 7) is needed in the area where

the processing crates are loaded with filled jars. A

reinforced shelf beneath the table top is convenient

for storing empty jar trays.

Fi^giçe^7.T—Loading table.

Storage Shelves

Shelves of the type shown in figure 20, page 21, are

needed for the final cooling of the processed food

before it is released to the patrons of the canning

center. The shelves, slatted to expedite cooling of

the jars, are built in sections so that they may be

easily removed for cleaning. The retaining strip

at the front of the shelves is painted with blackboard paint so that the shelves may be marked to

identify each patron's products.

PARTIAL LIST OF SUPPLIERS OF CANNING EQUIPMENT

Canning equipment may be obtained from the

following suppliers:

Chisholm-Rvdcr Co., Inc., 5280 Highland Avenue, Niagara

Falls, N. Y.

Dixie Canner Co., Athens, Ga.

Food Machinery Corporation, 101 East Maple Street,

Hoopeston, 111., and San Jose 6, Calif.

F. H. Langsenkamp Co., Harmon and South Streets,

Indianapolis 25, Ind.

A. K. Robins & Co., Inc., Haltimore 2, Md.
LOCATION AND INSTALLATION OF EQUIPMENT

Retorts

Eetorts for processing in glass jars are placed in a

regular retort line where an overhead hoist is

available for lifting the crates. Retorts of the

size described here are spaced on 48-inch centers for

convenient operation and maintenance. If space

does not permit this arrangement, the retorts may be

placed closer, but 42 inches between retort centers is

the minimum. After being alined, the retorts are

leveled and then bolted securely to the floor to prevent their tipping or moving during loading or unloading and to ehminate the danger of breaking a

steam or air line.

On these retorts steam, air, and water are brought

in at the top. The high-pressure steam for venting

and the low-pressure steam for processing are

brought in through separate openings. (Highpressure is a relative term, indicating that the steam

pressure in the line is well above the pressure at

which processing is done. The actual pressure of the

high-pressure steam depends on the State or local

requirements for installing pressure vessels. Some

States require that it be held at approximately 45

pounds by a pilot-operated pressui^e-reducing valve

in the main steam line. The high-pressure Hne

is, in effect, a bypass around the controller in the

low-pressure line.) With steam coming in at the

top, venting is done through a 1-inch drain at the

bottom. A J^-inch pet cock is provided on the

drain to bleed the retort during processing. These

fixtures and others necessary for processing and

pressure-cooling glass jars and small-size tin containers (No. 2j No. 2J^, and No. 3) are shown in

figure 8.

Figure 9 shows the same retort Avith added facilities

for pressure-cooling No. 10 tin containers. Water

is brought in at the bottom as well as at the top of

the retort to speed the cooling operation.

An overflow pipe is provided to carry off the

excess water during the cooling period. A spring

relief valve on the overflow assembly is used to

prevent the building up of excess pressure in the

retort during the cooling operation. This valve is

set to operate at a pressure slightly lower than that

of the pop safety valve in the retort lid. When the

retort is used for processing and cooling glass jars

both gate valves in the overflow assembly are

closed.

A satisfactory method for installing a battery of

retorts is shown in figure 10. It is a practical method

for use in community canning centers, as one

automatic control valve on a common header

regulates the temperature of all of the retorts in the

line. The low-pressure steam header must be at

least 3 inches in diameter. This size of header will

furnish an adequate supply of steam to as many as

six retorts. The header is assembled in the desired

length with threaded pipe connections (figs. 10 and

11A), or it may be made from a single pipe with

nipples welded at the take-off points (fig. lie.) To

facilitate the removal of condensate, the header is

sloped }/2 iiii^h per 10 feet toward the steam trap.

The pop safety valve, set at 15 pounds pressure,

will prevent the building up of excessive pressure in the header. The %-inch connecting line

between the low-pressure header and the retort is

equipped with a gate valve, rather than a globe valve,

so as to reduce resistance to the steam flow during

processing.

For maximum efliciency use the sizes of pipe

indicated for steam, air, and water. Place the

header pipes close to the retort line and cover the

steam header pipes with asbestos or any suitable

insulation. Fit the steam, air, and water lines between the headers and retorts with the proper kind

of hand valves specified in figure 10. These valves

should be of the right sizes jmd designed for the

purposes intended. Do not use water valves on

steam lines or vice versa. All valves used should be

constructed of noncorrosive metal, preferably bronze.

They should be built to withstand pressure up to

125 pounds per square inch and have replaceable

seats, plugs, or discs. If the working parts of the

valves are replaceable the cost of maintaining the

valves will be greatly reduced.

Y-type strainers are provided on the steam and

air lines leading to the automatic control valves to

keep scale and trash out of the working parts of

the valves. A T-type strainer is provided on the

water line near the retort assembly to reduce the

possibility of clogging the spray nozzles in the lid of

the retort with rust and sediment. This strainer is

in addition to the one built into the water line on

each retort. A gage is desirable on the water line

near the retort assembly in order to know the water

pressure in the line. It is essential to have at least

25 pounds gage pressure on the water line at the

retort to insure proper operation of the spray

nozzles. A gage on the air Une near the retort

assembly would also be desirable for determining

the setting of the air-control valve.

The pressure gage on the low-pressure steam

header is needed in order to adjust the pressure

control valve and to show whether the pressure on

the line is being maintained. For ease of reading,

it is desirable to have the pressure gages at eye level.

Retorts installed as shown in figure 10 may be

used for processing and pressure cooling glass jars

or small-size tin containers. If No. 10 cans are

also used it will be necessary to add the extra piping

facilities shown in figure 9.
1/4 WATER VALVE

PRESSURE GAGE

0-30 LBS.

SAFETY VALVE 3/V

,-•-1/4" PETCOCK

1/4"

GLOBE VALVE

-AIR^

1/2 GLOBEVALVE

(Low Pressure

Steam)

I20*-- 270* F

¿THERMOMETER

INSTALL

CONTROL

VALVE

HERE

1/2 GLOBE VALVE

HIGH PRESSURE STEAM

-I GATE VALVE

DRAIN

Figure 8.—Retort for glass jars and small tin containers.
SAFETY VALVE

3/4"

1/4" PETCOCKPRESSURE GAGE

0-30 LBS. .STRAINER

1/4" WATER VALVE

l/4"pL0BE VALVE

AIR

3/4" ADJUSTABLE , ,

RELIEF VALVE ^'"^

I GATE

VALVE

DRAIN

Figure 9.—Retort for glass jars and tin containers of all sizes.

9
AIR PRESSURE GAGE 0-30 LBS.

STEAM PRESSURE GAGE 0-30 LBS.

3/4" GATE VALVE'^

STEAM LINE TO

ATMOSPHERIC COOKERS "N

(OPTIONAL) i

/

1/2" LOW PRESSURE /

STEAM TRAP '

1/2" HIGH PRESSURE

STEAM TRAP

3/4" AIR CONTROL VALVE^ \

3/4" WATER STRAINER

Figure 10.—Piping arrangement to a battery of retorts for processing and pressure-cooling glass jars and small-size tin containers.
Automatic Control Valves

Pressure Control Valve

The proper installation of a back-pressure pilotoperated valve to control the temperature in a

battery of retorts is shown in figure 10. The valve

is installed on a %-inch steam line between the main

steam supply line and the 3-inch header. To

enable the valve to operate at peak efficiency, the

following should be kept in mind: (1) The length

of the pipe between the main steam line and the

valve, and between the valve and the header, is

kept short; (2) a strainer is installed between the

main steam line and the valve; (3) the pilot opening

on the valve is connected to the header by means of

a 34"iiich feeler line to enable the valve to respond

quickly to pressure changes in the header; and (4) a

steam trap is installed on the high-pressure steam

header to remove condensate, thus insuring a goodquality steam.

Prior to processing in the retorts, the steam is

turned on and the valve is adjusted to operate at a

specified pressure. The pressure required to maintain a temperature of 240° F. in the retort will vary

with the altitude of the place where the processing

is done (table 3, p. 22). To determine the pressure

setting of the valve, note the reading of the pressure

gage on the steam header. After this control valve

has been properly adjusted it will require very little

attention from the operator.

The pilot-operated pressure-control valve is as

satisfactory on a single retort as on a battery set-up.

On a single retort a smaller valve is used. The

valve is installed on the 3^-inch steam line leading

to the retort at the place indicated in figures 8 and 9.

The pilot is connected to the retort shell by means

of a 3^-inch feeler line.

installed on a ^-inch steam line between the main

steam supply line and the low-pressure header. It

operates automatically in response to temperature

changes within the low-pressure steam header.

An air-actuated tempeiature-control valve is

recommended for use on single retorts, as well as on

a battery installation. On a single retort a smaller

valve is used. It is installed on the 3^-inch steam

line leading to the retort at the place indicated in

figures 8 and 9. The thermal bulb is installed near

the thermometer in the retort shell where it is fully

exposed to the steam.

Temperature-Control Valve

Figure 11 shows two hook-ups for an air-actuated

temperature-control valve. The hook-up shown in

figure 11A is for the same steam header as that

shown in figure 10. The hook-up shown in figure

11^ is an alternate arrangement on a welded steam

header. Either hook-up is satisfactory, but in

figure llA the thermal bulb is installed in a plate

welded in the end of the header rather than in a

screwed fitting. This welded installation eliminates

the mass of metal which otherwise would surround

the bulb and act as a source of heat, thus delaying

the response in the controller when the temperature

in the header drops.

In both installations (fig. 11A and B) a pet cock

is provided in the bulb end of the header. It is

always kept open sufficiently to provide a continuous

flow of steam past the bulb. The control valve is

/ ^ > M m- sAr£TY mi^

AM TeAP/^

B

ST£AM reAP'

Figure 11.—Temperature-control valve: A^ On threaded-pipe header; ß, on welded header.

11
Air Compressor

For maximum efficiency the air compressor is

located as close as practical to the retort line. The

compressor may be located in the boiler room or in

any convenient place in the canning plant proper

but the distance between it and the retorts should

not exceed 20 feet. If the compressor is located

inside the canning plant, place it above the floor

level; out of the way of patrons, and where it will

not get wet.

For best results use a %!-inch air-header pipe

between the compressor and the retorts. However,

if there is an abundant supply of air a 3^-inch pipe

will be adequate. Reduce it to 3<i inch before it

enters the retort. Install the air-control valve near

the retort assembly as shown in figure 10.

Consult a licensed electrician or a local power

company representative for information on the size

of wire to use for supplying current to the compressor

motor. Do not use an ordinary household extension

cord. It is not designed to carry enough current

to supply a motor of sufficient horsepower to run the

compressor.

Atmospheric Cooker

The atmospheric cooker may be operated off of

either the high- or low-pressure steam headers. The

low-pressure header is preferable because its pressure

is uniform and less attention is required by the

operator in adjusting the hand valve. Locate the

No. 2 cookers close to the regular processing area,

if possible, and where there is adequate floor drainage. The No. 3 cookers must be located in the

retort line where a hoist is available for lifting the

heavy cover and the crate. To provide space for

the cover, when the crate is removed, place the

cooker at the end of the retort line. To regulate the

steam supply to the cooker, install a J/2-iiich globe

valve between the steam-supply pipe and the rubber

hose on the cooker as shown in figure 12. Undeç no

circumstances should this valve be installed between

the hose and the cooker cover. With such an installation there would be no way of turning off the

steam if the hose should break.

Figure 12.—No. 2 atmospheric cooker installation.

12
External Cooling Sprays

External cooling sprays used for cooling products

processed in a retort are located under the same

overhead track as the retorts. Products processed

in atmospheric cookers are cooled under the same

sprays if the cookers are located in the retort line.

If, however, these cookers are placed at some

distance from the retort line additional sprays may

need to be installed near the cookers.

Regardless of the location of the cooling sprays,

the nozzles must be mounted at least 18 inches

above the crates so that the jars will get the full

benefit of the sprays (fig. 13). Other essential

features are: (1) Adequate drainage to carry off

the cooling water promptly ; (2) slatted wooden platform to keep the crate of jars off of the cold cement

floor and to facilitate drainage; (3) baffles to confine

the water and prevent splashing. In those canneries

where the cooling tank for tin containers must be

used for glass jars, a similar platform should be

placed in the bottom of the tank and the drain

should be kept open to carry off the water promptly.

Water should never be allowed to back up on the

jars as this may cause them to break.

212370—.52-

Figure IS.^External cooling sprays bein^ used.

13
SOME KEY POIXTS ©X EQUIPME:^T MAIXTEXAXCE

Spray Biozzles

Spray nozzles in the lid of the retort need to be

checked before each cooling operation to see that

they are working properly. If the nozzles mounted

in the spray ring (fig. 14) get clogged, remove the

entire ring before taking the nozzles apart so that

they can be worked on conveniently. If the single

nozzle in the lid of the retort gets clogged remove the

coupling with the nozzle. Otherwise, the core in the

nozzle may drop out and get lost. To clean the

nozzles, unscrew the end and remove the core with

tweezers. Do not attempt to remove the core by

pushing a wire or sharp instrument through the

hole of the nozzle as this may damage the core or

enlarge the hole. Wash the core carefully to remove rust or sediment that may be present. When

encrusted from the use of hard water remove deposits with dilute hydrochlpric acid or radiator

cleaner. Wash the end of the nozzle, too, then

replace the core in its original position and reassemble

the nozzle. After mounting in the lid turn the

water on to see that the desired spray pattern is

obtained. The nozzles on the external sprays are

cleaned in the same manner except that pointed-nose

pliers, instead of tweezers, are used to remove the

cores fi'om the larger nozzles.

Strainers

The small strainer in the connecting pipe between

the water valves and the hose on the retort lid

needs to be cleaned at least once a week during the

canning season. If difficulty is encountered with

rust and sediment in the water supply it may need

to be cleaned oftener. To clean the strainer, remove it from the connecting pipe. Wash it under

running water or blow the sediment out with compressed air. When all sediment has been removed

replace the strainer. The Y-type strainers in the

steam and air lines and the T-type strainer in the

water line also need to be cleaned occasionally

during the canning season.

Air Compressor

To keep the air compressor in good working.

condition clean the air filter once a week. At the

same time drain the storage tank of condensate.

It is also important to drain the tank at the end of

the canning season to avoid possible damage by

freezing. For care of the motor on the compressor

follow the manufacturer's instructions.

SPRAY NOZZLES

Figure 14,—Location of spray nozzles in retort lid.

14
PROCEDURE FOR OPERATING TRE EQUIPMENT

These procedures for operating retorts, atmospheric cookers, and cooling sprays will assure good

results if the basic requirements for installing the

equipment have been complied with.

Operating Retort When Processing Under Pressure

Whether processing is to be done in glass jars or

in small-size tin containers the procedures for

operating the retort are basically the same. Precautions need to be taken, however, when glass jars

are used to avoid sudden changes in temperature

that might cause breakage. Also to be considered

is the possibility of liquid boiling out of the jars

because of a sudden drop in pressure. Nevertheless,

no difficulty should be encountered with glass jars

if the steps given for operating the retort during

processing and cooling are carefully followed.

A. Getting retort ready and loading :

1. Open water valves F and G {fig. 15) to see that

nozzles in lid are working properly.—All nozzles

should give off a uniform cone-shaped mistlike

spra^^ If the spray is not uniform the nozzles are

clogged and need to be cleaned before processing is

started. (For instructions on cleaning nozzles, see

p. 14.)

2. Close water valves F and G after testing sprays,

3. Open steam valves A and B to blow out condensate in high- and .low-pressure steam lines.—This

should be done for the first load of jars and for subsequent loads if the retort has been allowed to

cool. Otherwise the condensate coming in contact

with the jars may cause breakage.

4. As soon as steam flows freely close valves A

and B.

5. Open wide the drain valve C and pet cock D in

drain line.—It is essential to drain water from retort before loading.

6. Lift crate of filled jars into retort; close and

tighten retort lid.

7. Close pet cock or vent valve on lid of retort.

B. Venting retort and raising temperature:

1. Check to see that drain valve C and pet cock D

in drain line are wide open.—This is essential for

rapid remov^J of air and condensate during initial

venting period.

2. Open steam valve A to high-pressure line

gradually and to the extent necessary to bring retort

up to 212"^ F. in 10 to 15 minutes. The extent to

which the valve is opened will depend on the steam

pressure in the line. If the valve is opened too

quickly breakage may occur.

3. When retort thermometer registers 212^ F. and

steam flows from drain under positive pressure, close

drain valve C. Leave pet cock D wide open.—If

there is any obstruction in the pet cock, slightly

open drain valve C as some venting from the

bottom of the retort is essential throughout the

come-up and processing periods. During the comeup period careful attention is required to see that

pressure in the retort does not exceed by more than

1 or 2 pounds the pressure at which processing will

be done. Otherwise the safety valve may blow.

4. When the retort temperature reaches that required for processing {240° F.), or 1° or 2° higher,

close high-pressure steam valve A, then open quickly

and fully the low-pressure steam valve B.—It is important to operate these valves in prompt sequence

to prevent a lag in steam flow and consequent

drop in retort temperature. If, however, a pronounced drop should occur, open the high-pressure

steam valve A and close the low-pressure steam

valve B to bring the temperature up again. This

may require from 3 to 5 minutes. When the processing temperature is reached again switch to the

low-pressure steam as indicated above. If difficulty is still encountered in maintaining the required

processing temperature too much steam may be

venting from the bottom of the retort or the installation of the low-pressure steam line may be faulty.

C. Processing at constant temperature:

1. When the required processing temperature of

240° F. is reached and the temperature and pressure

readings are in agreement, start counting the processing

time.

2. Operate the retort at the required temperature

for the full time specified in the processing instructions.

15
VALVEAIR-"E';

GLOBE VALVE

(LOW Pressure Steam)

"B" ^

120**-270* F

THERMOMETER

WATER VALVE -

PRESSURE GAGE

SAFETY VALVE

—PETCOCK -H*

INSTALL

CONTROL

VALVE

HERE

GLOBE VALVE- A

HIGH PRESSURE STEAM

DRAIN-"C

Figure 15.—Retort showing valves used during operation»

16
Operating Retort When Cooling Under Pressure

A. Maintaining pressure:

1. As soon as processing is completed close pet

cock D in drain line.

2. Close low-pressure steam valve B.

3. Open air valve E to maintain retort pressure at

1 or 2 pounds above processing pressure.

NOTE :—In changing from steam to air to maintain pressure

in retort, care must be taken to avoid a drop in pressure of

more than 2 pounds. Otherwise liquid will boil out of the

jars. If the above steps are carried out in prompt sequence,

however, there will be no appreciable drop in retort pressure.

B. Bringing temperature down:

D. Unloading retort:

1. Open retort lid and carefully transfer crate of

jars to external cooling sprays.

Cooling Under External Sprays

When starting to cool jars under external sprays,

care will need to be taken to avoid breakage from

shock even though the jars are partially cooled in

the retort. This is necessary because the heat at

the center of the jars will have moved outward and

reheated the jar surface. To minimize the change

in jar temperature, cooling should be carried out

promptly as follows:

1. Open valve to the No. 1 cooling spray quickly

and fully to get a fine mistlike spray. (Fig. 16.)

2. After 1 minute of cooling under the No. 1

spray open the valve to No. o cooling spray.

1. Open water valve F to single cooling spray in lid

quickly and fully to get a fine mistlike spray.—If

turned on slowly water droplets will be too large

and, on contact with hot jars, may cause breakage.

2. When retort temperature has dropped to 190° F.

as indicated by retort thermometer, open water valve G

to multiple cooling sprays quickly and fully to speed

up cooling.—Products with a short process time

will cool faster than those with a long process time.

In any case when the temperature of the retort is

190° F. the jars will be sufficiently cool to withstand

the shock of the additional cooling water.

3. Continue cooling with all sprays wide open in

order to reduce the temperature of the jars to a point

where they may be safely removed from the retort.—

Fast-cooling products will be cool enough when the

retort temperature is down to 140° F. For slowcooling products such as cream-style corn, pumpkin,

spinach, and meats it will be necessary to continue

cooling until the retort temperature is down to 120°.

Jars not sufficiently cooled as directed sometimes

explode on release of retort pressure.

C. Bringing pressure down :

1. When the required cooling temperature is attained, close air valve E.

2. Open pet cock D and drain valve C and allow

pressure in retort to drop to 0 pounds.

3. Close water valves F and G.

4. Open pet cock or vent valve in lid of retort to

release any pressure that may be left in the retort and

to allow the water to drain out freely.

VALVE

C00LÍN6

Aaö:

0

SPRAY

NO sy

COOL

nos

SPRAY

two

......^

^nCOOLIHO . SM*Y

Figure 16.—External cooling sprays.

3. Continue cooling with both valves wide open

until the temperature of the jar contents is about

100° F. This can be determined by shaking the

jar and holding it against the bare arm. It should

feel just slightly warm.

4. When jars have cooled sufficiently place them

on storage shelves, as described on page 21, until

completely cold.

Operating Atmospheric Cooker

These procedures for operating the atmospheric

cooker (fig. 12, p. 12) are intended for glass jars

but they may also be used for tin containers. When

processing in tin, the precautions necessary to

prevent thermal shock to glass jars need not be

taken.

A. Getting cooker ready:

1. Fill base pan with water.—This may not be

necessary after the first loading of the day as the

condensate formed during processing will usually

keep water level up to the overflow.

17
2. Open steam valve to blow out condensate in

steam line.—This should be done for the first load

of jars and for subsequent loads if the cooker is not

being used continuously. Otherwise condensate

coming in contact with jars may cause breakage.

3. As soon as steam flowsfreely^ close valve,

4. Close pet cock on cover.

B. Loading cooker:

1. Place loaded crate of jars on center of support

in base pan.

2. Lower cover into place over cooker crate with

bottom of cover centered on projecting legs of crate

support.—This is important to assure good steam

distribution in the cooker and to have as uniform

venting as possible around the bottom of the cover.

C. Raising and maintaining temperature:

1. Open steam valve—slowly for the first half

minute to avoid shock to the jars—then continue

opening valve until steam bubbles freely through water

in base pan.—This bubbling action at the beginning

of the operation indicates that air is being vented

from the cooker.

2. l^^fíl^'^ie >^!^ired processing temperature is

reached; (212^^ ^ff^.¡^^^^-lMel), as indicated on the

thermometer^ and líiMmc^ in the base pan is boiling,

start counting the processín^'^ñme.

3. Throttle the steam so that only a small quantity

escapes through the waier seal.—Tais is important

not only to prevent waste of steam after the cooker

is up to temperature but to avoid vigorous splattering

of hot water from base pan that may cause serious

burns.

4. Operate the cooker at the required temperature

for the time specified in the processing instructions.

D. Unloading cooker:

1. As soon as processing is completed close steam

valve.

2. Open pet cock on cover.—This will prevent a

vacuum from forming in the cooker when the steam

is turned off.

3. Lift cover of cooker and carefully transfer crate

ofjars to external cooling sprays.

4. Cool jars promptly under external sprays in

accordance with instructions given on page 17.

Operating Retort at

212^ to 216^ ¥.

The retorts described herein for processing low

acid foods at 240° F. may also be used for processing

acid foods in steam at 212° to 216° as follows:

A. Getting retort ready and loading :

1. Open water valves F and G {fig. IS) to see that

nozzles in lid are working properly.—All nozzles

should give off a uniform cone-shaped mistlike

spray. If the spray is not uniform the nozzles are

clogged and need to be cleaned before processing is

started. (For instructions on cleaning nozzles, see

p. 14.)

2. Close water valves F and G after testing sprays.

3. Open steam valves A and B to blow out condensate in high- and low-pressure steam lines.—This

should be done for the first load of jars and for subsequent loads if the retort has been allowed to cool.

Otherwise the condensate, coming in contact with

the jars, may cause breakage.

4. As soon as steam flows freely, close valves A

and B.

5. Open wide drain^ valve C and pet cock D in

drain line.

6. Lift crate of filled jars into retort; close and

tighten retort lid.

7. Close pet cock or vent valve on lid of retort.

B. Venting retort and raising temperature:

1. Open steam valve A on high-pressure steam line.

—Open valve slowly at first to avoid shock to the

jars.

2. When the retort thermometer registers 212° F.

and steam flows freely through the drain, open lowpressure steam valve B and close high-pressure steam

valve A.

3. Partially close drain valve C and adjust steam

valve B to maintain a temperature, of 212° to '216° F.

The slight pressure required to obtain a temperature

of 216°—approximately 2 pounds at sea level—will

assure good steam distribution in the retort.

C. Processing at constant temperature:

1. When retort temperature is at 216° F. start

counting the processing time.

2. Process for the full time specified for 212° in the

processing instructions.

D. Cooling in retort and unloading:

1. As soon as processing is completed close steam

valve B and open pet cock or vent valve in the lid of

retort.

2. Open water valve F to single cooling spray in

lid, quickly and fully, to get a fine mistlike spray.—If

turned on slowly water droplets will be too large and,

on contact with hot jars, may cause breakage.

3. After 1 minute of cooling under the single spray,

open water valve G to multiple cooling sprays, quickly

and fully, to speed up cooling.

4. Complete cooling in the retort or open retort

lid and transfer crate ofjars to external cooling sprays

for final cooling. (See instructions given on p. 17.)

18
GLASS JARS AND CLOSURES

Selecting Jars and Closures

Use standard mason jars designed for home canning when processing by the methods described

herein. It makes no difference whether they are

regular or wide-mouthed but they should be of a

type that can be sealed with two-piece metal closures

(fig. 17). This is the only type closure that is

entirely satisfactory. It permits the jar to vent

during the processing period even though the band

is screwed down firmly and it is self-sealing. Being

of metal the lid helps to absorb the initial shock to

the jar when the cold water sprays are turned on for

cooling. The lids of the two-piece metal closures

must be new. The screw bands may be reused if

they will screw down evenly. Carefully examine

all jars, whether new or previously used, for defects

such as cracks, chips, uneven sealing surfaces,

rough edges on rims, or rims that are not perfectly

round. Pay particular attention to the tops of the

jars. Even the smallest defects that are difficult

to see may cause'a poor seal. Feel the tops of the

jars with the fingers and look through the jars while

holding them up to the light.

Metal

screw band

Metal lid

with sealing

compound

Seals here

Figure 17.—Standard mason jar with two-piece metal

closure.

The size of jars that may be used will vary with

the product. Fruits, tomatoes, and other acid

foods may be canned in pint, quart, or 2-quart jars.

Use only pint and quart sizes, however, for lowacid vegetables and meats. These are the only

sizes for which processing times are available. The

processing instructions specify the sizes that may

be used for each product.

Do not use glass jars that are not intended for

canning, such as coffee or mayonnaise jars. These

odd jars create problems in stacking and are quite

likely to break during processing or cooling. Old

style mason jars with flat bottoms and straight

sides also create problems. These jars, because of

their shape, are known to break readily when used

for processing by the methods given herein.

If the proper jars are used and the methods given

for handling; and processing them are carefully

followed, breakage should not exceed 3 jars per

thousand.

Estimating Nnmber of «larii Needed

The number of jars needed for canning a given

quantity of fruits, vegetables, meats, or poultry

may be estimated from tables 1 and 2.

TABLE 1.—Approximate number of jars required for

mecùsured quantities of produce

Produce

Weight

per

bushel 1

Pint jars Quart

jars

2-quart

jars

Apples _ ___

Pounds

48

48

45

32

30

52

2 36

50

56

35

20

48

50

30

56

18

40

55

56

Number

36

42

22

14

35

37

30

36

53

17

34

44

45

14

50

15

36

40

38

Number

18

21

11

17

18

15

18

26

8

17

22

23

7

25

7

18

20

19

Number

9

Apricots

Asparagus

10

Beans, green lima

(in pods)

Beans, green and

wax

Beets (without

tops)- . _ _

Berries- _ _ 8

Carrots

(without tops) -

Cherries- _ 13

Corn, sweet

(in husks) _ _

Olira _

Peaches 11

Pears __ _ 12

Peas, green

(in pods) _ _ - _ _

Plums - 13

Spinach _

Squash (summer).

Sweetpotatoes

Tomatoes

_-- _^

1 Legal weight of a bushel of produce varies in different

States. These are average weights.

2 24-quart crate.

19
TABLE 2.—Approximate quantities of beef, pork, or

chicken required to fill jars of specified sizes

Meat

Quantity required to fill a—

Pint jar Quart jar

Beef, round (untrimmed)

Beef, rump (untrimmed)

Chicken (dressed, undrawn) to _ _ _

be canned with bone

Pounds

lMto2

3 to3K

2HtoSys

41/4 to 4M

3to3M

Pounds

3to3H

5io5y2

4M to 5M

Chicken (dressed, undrawn) to___

be canned without bone

Pork loin (untrimmed)

7 to 8

5 to5M

Washing and Tempering Jars

Sealing Jars

Seal jars promptly after filling as follows:

1. Check to see that there are no food particles

on top to prevent a good seal.

2. Put lid on with seahng compound next to the

glass.

3. Screw metal band down so that it is even all

the way around. Screw-it firmly, using the fingers,

not the palm of the hand (fig. 18). Overtightening

of the bands may prevent proper venting of the

jars during processing.

Warning:—These two-piece closures are self-sealing. Do not tighten them further when removing

jars from the processing crate. Any attempt to do so

may break the seal.

To get jars ready for canning, rinse new ones

thoroughly in warm water. Wash those that have

previously been used, in hot soapy water, then

rinse. Wash the screw bands, too, if they have been

used.

The metal lids with sealing compound do not

need any special preparation. They may be taken

directly from the package and placed on the jars

at the time of seahng unless the manufacturer's

directions specify otherwise.

To avoid breakage when filHng jars with hot

products, temper them by placing them in a steam

box or by dipping them in hot water just before

filling. Another method of tempering jars is to

start with a small quantity of the hot product and

slosh it around in the jars.

Pointers on Filling Jars

For products that are packed in a liquid medium

(sirup or water) put from 13^ to 2 inches of liquid

in the jar before packing the product. As the

product is added, the liquid will rise in the jar and

force the air out, thus eliminating the need for

bubbhng jars. When the product is packed to the

head space specified in the processing instructions,

add just enough hquid to cover the product. Be

sure the liquid is boiling hot. The hotter products

are at the time the process is started the better.

With all products some head space should be left

in the jars. The head space is the distance between

the top of the product and the top of the jar. It

will vary from }4 inch to 1 inch, depending upon the

product. The head space is necessary to allow for

the expansion of the product and the liquid during

processing. If the jars are filled too full, small

particles of food may get between the top of the jar

and the lid while the jar is venting and prevent a

good seal.

Figure 18.—Tightening screw bands.

Stacking Jars in Processing Crate

To properly load a retort or atmospheric cooker

crate, stack the jars upright and stagger them, as

shown in figure 19. This arrangement will assure

good circulation of steam and increase the efficiency

of the cooling process. It will also facihtate the

removal of air from the retort or cooker during

venting. When processing is to be done in a retort,

adjust the load in the crate so that when the Hd is

closed there will be a space of 6 to 8 inches between

the jar tops and the spray nozzles in the retort lid.

This is necessary to assure even distribution of the

water on the jars during cooling.

20
Figure 19.—Jars properly stacked in processing crate.

Air-Cooling Jars on Shelves

After the processed products are spray-cooled,

remove the jars from the crate and place them on

shelves for further cooling as shown in figure 20.

Jars of fruit are placed on their sides to distribute

the sirup evenly over the fruit. This helps to

prevent fruit from floating. When the jars are

completely cool, remove the screw bands so that

they will be in good condition for subsequent

canning.

Testing Jars for Proper §eal

Check jars to see that they are sealed before

releasing them to patrons. A metal lid is sealed if

the center of the lid is pulled inward or if a clear

ringing sound is produced when the center of the lid

is tapped with a spoon. A dull note, however,

does not always indicate that the jar is not sealed.

The vacuum may be too low or the product may be

too close to the top of the jar. When in doubt

about a seal, turn the jar partly over in the hands to

see whether it leaks, or lift the jar with the fingers on

the edge of the lid to see whether the seal holds. If

the jar is not sealed, the food should be recanned or

used immediately. If to be recanned, empty the

jar, heat the food, pack, and process as if the product

were fresh. Do not use the same jar again unless it

is free from defects. If there are no cracks or chips,

examine the lid to see whether the impression in the

sealing compound is uniform. If not, this would indicate that the sealing surface of the jar was uneven or

that the band was not properly applied. In recanning the product, be sure to use a new metal lid

and a screw band that fits evenly all the way around.

Figure 20.—Shelves for temporary storage of jars.

21
PROCESSlNCi TIME AXD TEMPERATURE REQVIREMEXTS

The processing times given in this publication for

both acid and low-acid foods, canned in glass jars,

take into consideration the fact that the jars are

spray-cooled at the end of the process. In general,

the processing times are longer than those recommended for products canned in glass jars that are

air-cooled. This is because the cooking is stopped

promptly at the end of the process by the cold

water sprays whereas with air-cooled products cooking continues during the initial cooling period and

this cooking is considered part of the process.

However, in determining the processing times, other

factors than the method of cooling, such as the style

of pack and whether the products were packed hot

or cold, were also taken into consideration. For

this reason the instructions given for each product

should be carefully followed.

Requirements for Acid Foods

The processing times for fruits, tomatoes, and

other acid foods are based on a temperature of 212° F.

—the temperature at which water boils and steam

condenses at sea level. This temperature is sufficient

to kill all actively growing bacteria and yeasts in

the time specified for each product and the acid

in the food prevents the growth of any heat-resistant

spores that may be present. The times are also

based on the assumption that the jars will be spraycooled at the end of the process, whether processing

is done in a boifing water bath, in an atmospheric

cooker, or in a retort at 212° to 216° F.

Acid foods processed by any one of these methods

may be air-cooled instead of spray-cooled at the

end of the process. If this is done, however, the

processing times for all products except cold-packed

tomatoes and fruit juices should be shortened by 5

minutes. The processing times for cold-packed

tomatoes should be shortened 10 minutes, but the

time for fruit juices should not be shortened at all.

Requirements for Loiv-Aeid Foods

The processing times given for low-acid vegetables

and meats are based on a temperature of 240° F.,

the minimum temperature necessary for destroying

heat-resistant spores of bacteria in a reasonable

length of time. To attain this temperature, processing must be done in a pressure vessel such as the

retorts described on page 1.

From the time the steam is turned on in the retort

until the products are processed and spray-cooled,

follow carefully the instructions given for operating

the retort. Be sure to vent the retort adequately to

remove all air before the process is started. An airsteam mixture in the retort will cause a nonuniform

heat distribution resulting in low-temperature regions

and possible underprocessing. Timing of the process

^should not begin even though the proper temperature

Is indicated until temperature and pressure instruments on the retort give corresponding readings (table 3).

When agreement is reached, record the time and

process for the full period required. If at any time

during the processing period the temperature drops

more than 5° below 240° F. the products should

be given a complete new cook, starting from the

time the retort is brought back to 240°. Should

there be a temperature drop of from 1° to 5°, 2

minutes should be added for each minute that the

temperature registered below 240°. For example,

in a 4° drop for 10 minutes it would be necessary to

add 20 minutes to the normal processing time.

If products must be reprocessed for any reason, they

must be reprocessed promptly in clean jars with new

lids for the full time given for that product in the

processing instructions.

Altitude Adjustment

When processing low-acid foods at the recommended temperature of 240° F. the corresponding

pressure gage reading will be 10.3 pounds at sea levelTo attain this temperature at altitudes above sea

level the pressure must be increased approximately

Yi pound for each 1,000 feet as shown in table 3.

TABLE 3.—Gage pressure corresponding to processing

temperature of 240"" F, at specified altitudes

Altitude

(feet above

sea level)

Gage pressure

Altitude

(feet above

sea level)

Gage pressure

0

500

1,000

2,000

Pounds

10.3

10.5

10.8

11.3

¡

3,000

4,000

5,000

6,000

Pounds

11.7

12.2

12.7

13.1

When processing acid foods at altitudes above sea

level the processing times will need to be increased to

compensate for the lower temperature at which water

boils and steam condenses. For example, at 2,000

feet above sea level the temperature of boiling

water or condensing steam is 208° F. instead of the

sea level temperature of 212° on which the processing

times are based. Therefore, acid foods processed at

208° must be processed for a longer time than that

given in the timetable in order to prevent spoilage.

For each 1,000 feet above sea level, 1 minute will

need to be added to the processing time if the time

given for the product is 20 minutes or less and 2

minutes for each 1,000 feet if the processing time

is more than 20 minutes. If a retort is used for

processing acid foods at 212° to 216° and the pressure

is increased sufficiently to maintain the temperature

at altitudes above sea level, it will not bë necessary

to increase the processing times.

22
PROCEDURE FOR CAXXIXG ACID FOODS

The procedures given for preparing and processing

fruits, tomatoes, and other acid foods are briefly

outhned in table 4. Some of the products are precooked and packed hot. Others are packed raw

and covered with boihng sirup. The method of

packing determines, in part, how long the products

must be processed. For this reason the instructions

should be carefully followed.

TABLE 4.—Time and température for processing fruits^ tomatoes^ and other acid foods

in glass jars that are to he spray-cooled

Produce Preparation steps

Time to process at

212° F. at sea level i

Pint Quart 2-quart

Min. Min. Min.

Apple butter Follow any good formula for making apple butter. Fill boiling hot

to within 34 inch of top of jar. Seal and process immediately.

15^ 15 15

Apples in sirup Wash, pare, and core apples. Slice or quarter. Drop into salt

water to prevent browning. Drain, then boil 5 minutes in thin

sirup or water. Fill boiling hot to within 3^ inch of top of jar.

Cover with hot sirup or water. Seal and process immediately.

20 25 30

Applesauce Make applesauce, sweetened or unsweetened. Heat to boiling point,

stirring to heat evenly and to prevent sticking. Fill boiling hot to

within 34 inch of top of jar. Seal and process immediately.

15 15 15

Apricots Wash apricots. Leave skins on or scald, cold dip, and remove skins.

Leave apricots whole or cut in half and remove pits. Fill jars to

within Pi, inch of top. Cover with boiling sirup. Seal and process immediately.

30 35 40

Berries, except

strawberries

Wash berries and drain well. Fill jars to within 3^ inch of top.

Shake while filling for a full pack. Cover with boiling sirup.

Seal and process immediately.

15. 20 25

Cherries, sour Wash cherries, chill in ice water, and pit. Fill jars to within 3^ inch

of top. Shake while filling for a full pack. Cover with boiling

sirup or water. Seal and process immediately.

25 30 35

Cherries, sweet Follow directions for sour cherries. Pits may be left in. 25 30 35

Fruit j uices Wash fruit, remove pits if desired and crush fruit. Heat to simmering. Strain through cloth bag or put through juice extractor.

Add sugar, if desired, 3^ to 1 cup to 1 gallon of juice. Reheat to

to 180° F. Fill to top of jar. Seal and process immediately.

5 5 5

Peaches, in sirup __. To can freestone peaches, wash, scald, cold dip, and remove skins.

Cut peaches in halves or slices. Remove pits. Drop into salt

water to prevent browning. Drain. Fill jars to within 3^ inch of

top. Cover with boiling sirup. Seal and process immediately.

To can clingstones, follow the directions given for freestones but

peel peaches by hand or lye peel them.

30 35 40

Peaches, sliced,

solid pack

Use soft-ripe peaches. Wash, scald, cold dip, and remove skins.

Slice peaches, removing pits. Add >^ cup of sugar per quart of

sliced peaches or can them without sugar. Do not add water.

Heat peaches slowly to boiling temperature. Stir carefully as

needed to heat them evenly. Pack hot into jars to within 3^ inch

of top. Seal and process immediately.

30 35 40

Pears To can Bartlett and other mellow pears wash, peel, cut in halves,

and core. Drop into salt water to prevent browning. Drain.

Fill jars to within 3^ inch of top. Cover with boiling sirup. Seal

and process immediately. To can sand pears and other varieties

that are difficult to mellow follow the directions given for Bartletts but cook them in water or light sirup until tender before

filling them into jars, otherwise the processing times will not be

adequate.

30 35 40

See footnote at end of table.

23
TABLE 4.—Time and temperature for processing fruits^ tomatoes, and other acid foods

in glass jars that are to he spray-cooled—Continued

Profliiff Preparation steps

Time to process at

212° F. at sea level ^

Pint Quart 2-quart

Plums Wash plums. Can whole or, if freestone varieties are used, they

may be halved and pitted. If whole plums are used press them

down closely while packing. Fill jars to within J^ inch of top.

Cover with boiling sirup. Seal and process immediately.

Heat well-fermented sauerkraut to simmering. Do not boil. Pack

hot kraut into jars to within 3^ inch of top. Cover with hot

kraut juice or weak brine. Seal and process immediately.

Use only perfect, ripe tomatoes. Wash, scald, cold dip, and remove

skins. Cut core out. Pack whole or quartered. Press gently

to fill space in jars. Fill jars to within 3^ inch of top. Add salt,

if desired, but do not add water. Seal and process immediately.

Peel, core, and quarter tomatoes as for packing raw. Place in

open kettle and bring to boil, cooking the tomatoes until all are

hot. Stir frequently so that tomatoes will heat evenly. Fill

boiling hot to within K inch of top of jar. Add salt, if desired.

Seal and process immediately.

Use ripe, juicy tomatoes. Wash, remove stem ends, cut into pieces.

Simmer until softened, stirring often. Put through strainer or

juice extractor. Add 1 teaspoon salt to each quart juice. Reheat at once just to boiling. Fill boiling hot juice to within M inch

of top of jar. Seal and process immediately.

Min.

25

20

45

15

15

Min.

30

25

55

15

15

Min,

35

Sauerkraut _ _

30

Tomatoes, cold pack

Tomatoes, hot pack.

Tomato juice

65

15

15

1 When using an atmospheric cooker or boiling water-bath, these tim es will be adequate at sea level only. At altitudes

above sea level, add 1 minute for each 1,000 feet when the processing time is 20 minutes or less and 2 minutes for each 1,000

feet when the processing time is longer than 20 minutes. (See statement on altitude adjustment page 22.)

TABLE 5.—Summary of time and temperature for processing fruits, tomatoes, and other acid foods in glass jars

that are to he spray-cooled

Produce

Time to process at

212° F. at sea level i

Pint Quart 2-quart

Minutes Minutes Minutes

Apple butter

Apples in sirup

Applesauce

Apricots _

Berries (except strawberries)

Cherries, sour

Cherries, sweet

Fruit juices

Peaches in sirup

Peaches, shced, solid pack__

Pears

Plums -

Sauerkraut

Tomatoes, cold pack

Tomatoes, hot pack

Tomato juice

15 15 15

20 25 30

15 15 15

30 35 40

15 20 25

25 30 35

25 30 35

5 5 5

30 35 40

30 35 40

30 35 40

25 30 35

20 25 30

45 55 65

15 15 15

15 15 15

1 When using an atmospheric cooker or boiling water bath these times will be adequate at sea level only. At altitudes

above sea level, add 1 minute for each 1,000 feet when the processing time is 20 minutes or less, and 2 minutes for each 1,000

feet when the processing time is longer than 20 minutes. (See statement on altitude adjustment page 22.)

24
PROCEDURE FOR CAJ^NING LOW-ACID VEGETARLES

The procedures for preparing and processing lowacid vegetables are briefly outlined in tableó. If the

instructions are carefully followed products packed in

liquid will have a closing temperature of at least 140°

F. This is the closing temperature on which the processing times are based. It can be readily attained if

the blanched or steamed products are not overcooled before filling into the jars and if the water or

sirup used to cover the products is at the boiling

point. Avoid overfilling the jars as the processing

times are based on a fairly loose pack. Spinach and

other greens should be filled by weight to avoid

overfilling. The processing times for products of

heavy consistency such as cream-style corn and

strained pumpkin or squash are based on a riiinimum

initial temperature of 160°. The initial temperature

is the average temperature of the jar contents at the

time the steam is turned on for the process and it is

considered part of the process. Therefore, these

slow-heating products should not be allowed to

cool below a temperature of 160° before processing

is started. Otherwise the processing times will not

be adequate.

To take the initial temperature of cream-style

corn or pumpkin, set aside the first 2 jars that are

filled. Place the lids on them but do not screw

down the bands. Just before closing the loaded

retort and turning on the steam, remove the lids

from the jars, stir the contents, and take the temperature. This will give the average temperature of

the coldest jars in the retort. If the initial temperature drops below 160° F. it will be necessary to increase the processing time 5 minutes for each 20°

below 160°. However, it is preferable to process a

partial load rather than allow the temperature of the

products to drop below that specified.

TABLE 6.—Time and temperature for processing low-acid vegetables in glass jars that are to he spray-cooled

Produce Preparation steps

Time to process

at 240° F. (10.3^

lb. pressure at

sea level)!

Pint _Qaaitei:

Asparagus, cuts

Asparagus, spears __

Beans, green and

wax (cut)

Beans, green lima-_

Beets, whole, cubed,

quartered, or

sliced

Carrots, whole,

wedged, cubed, or

sliced

Wash asparagus. Cut off tough ends and the leaf scales if they are large and

loose or soi is present underneath them. Wash again. Cut into 1-inch pieces.

Blanch. Fill hot to within 3^ inch of top of jar. Do not pack too firmly. Add

salt. Cover with boiling water. Seal and process immediately.

Follow directions given for preparing asparagus cuts but leave spears whole.

Group them and cut to fit pint jars. Do not use larger size jars. Pack into

jars, spear ends up, leaving 3^ inch space at top of jar. Add salt. Cover with

boiling water. Seal and process immediately.

Wash beans. Snip ends, cut into 1-inch pieces. Blanch. Fill hot to within 3^

inch of top of jar. Add salt. Cover with boiling water. Seal and process

immediately.

Can only young tender beans. Shell; wash. Blanch. Pack hot to within 1 inch

of top of jars. Add salt. Cover with boiling water. Seal and process immediately.

Sort for size. Cut off beet tops, leaving an inch of stem. Also leave root. Steam

beets at 230° F. (6 lb. pressure) until skins slip. Remove skins and trim.

Leave baby beets whole and cube, quarter, or slice larger beets. Pack hot

to within }4 inch of top of jar. Add salt. Cover with boiling water. Seal

and process immediately.

Wash carrots. Peel by preferred method. Leave small ones whole. Cut larger

ones into wedges, cubes, or slices. Blanch. Pack hot into jars to within }4 inch

of top. Add salt. Cover with boiling water. Seal and process immediately.

Min.

30

30

25

45

35

30

Min,

35

30

50

40

35

See footnote at end of table.

25
TABLE 6—Time and temperature Jor processing low-acid vegetables in glass jars that are to he spray-cooled—

Continued

Produce

Corn, cream styleCorn, whole kernel

Greens, spinach

and others

Mixed vegetablesOkra .

Peas, greenPumpkin or squash,

(strained)

Summer squash..

Sweetpotatoes in

sirup,whole or cut

Preparation steps

Husk corn and remove silk. Wash. Cut corn from cob at about center of kernel and scrape cob. Blend corn with boiling water, using about half as much

water as corn. Sugar and salt may be added to taste. Heat to boiling. Pack

boiling hot into pint jars to within 1 inch of top. Do not use larger size jars.

Seal and process immediately. The processing times for cream style corn are

based on a minimum initial temperature of 160° F. (See page 25 for statement on initial temperature. )

Husk corn, remove silk. Wash. Blanch on the cob in boiling water or steam

for 3 to 5 minutes. Cool in cold water and drain. Cut corn from cob at

about % depth of kernel. Do not scrape cob. Wash cut corn on screen to remove small particles of kernels. (Processes for whole-kernel corn may not be

adequate if small particles are not removed.) Pack corn loosely into jars to

within 1 inch of top. Add salt. Cover with boiling water. Seal and process immediately.

Pick over and wash greens thoroughly to remove all sand and dirt. Remove

tough stems and midribs. Blanch in steam or water until well wilted. Pack

hot greens loosely to within }4 inch of top of jar. (Maximum drained weight

for pints should be 13 oz.; for quarts, 23 oz.) Add salt. Cover with boiling

water. Seal and process immediately.

Combine tender, young vegetables such as cut green or waxed beans, cut asparagus, cut celery, baby lima beans, peas, and carrots. Do not use starchy vegetables such as potatoes or corn as the processing time will not be adequate.

Prepare vegetables as for canning separately. Mix in desired proportions.

Cover with water and bring to boil. Pack hot into jars to within 3^ inch of top.

Add salt. Cover with cooking liquid. Seal and process immediately.

Can only tender pods. W^ash; trim. Cook for 1 minute in boiling water. Cut

into l-inch lengths or leave pods whole. Pack hot to within 3^ inch of top of

jar. Add salt. Cover with boiling water. Seal and process immediately.

Shell and wash peas. Blanch. Pack hot to within 1 inch of top of jar. Add

salt. Cover with boiling water. Seal and process immediately.

Wash pumpkin or squash. Cut open and remove seeds and fiber. Cut into

sections, peel, and steam in a retort at 220° F. (23^ pounds pressure at sea

level) until soft. Or steam sections with rind on and scoop out meat. Put

through pulper. Heat pulp to boiling, stirring to prevent sticking. Pack hot

to within }4 inch of top of jar. Add no liquid or salt. Seal and process immediately. The processing time given for pumpkin and squash is based on a

minimum initial temperature of 160°. (See page 25 for statement on initial

temperature.)

Wash. Do not peel. Trim ends. Cut squash into 3^ inch slices; halve or quarter to make pieces of uniform size. Blanch. Fill hot to within 3^ inch of top

of jar. Add salt. Cover with boiling water. Seal and process immediately.

Wash sweetpotatoes. Sort for size. Steam in retort at 240° F. (10.3 lb. pressure at

sea level) for minimum time necessary to make skins slip, or lye peel them.

Can small sweetpotatoes whole. Quarter larger ones. Pack to within 1 inch

of top of jar. Guard against packing steamed sweetpotatoes too tightly. Cover

with boiling sirup (medium light). Seal and process immediately.

WARNING—The processing times given here are not adequate for solid-pack sweetpotatoes.

Time to process

at 240° F. (10.3-

Ib. pressure at

sea level)!

Min.

105

60

85

45

30

45

85

Min.

70

35

55

•105

50

35

50

125

45

65

1 At altitides above sea level it takes more than 10.3-pound pressure to attain a temperature of 240° F. (See table 3 for

gage pressure readings corresponding to 240° at various altitudes.)

26
TABLE 7.—Summary of time and temperature for processing low-acid vegetables in glass jars that are to he spraycooled

Produce

Asparagus, cuts

Asparagus, spears

Beans, green and wax, cut

Beans, green lima

Beets, whole, cubed, quartered, or sliced

Carrots, whole, wedged, cubed, or shced

Corn, cream style (initial temperature 160° F.)

Corn, whole kernel 1 ' oV ' \

Greens, spinach and others (maximum drained weight pints 13 oz.; quarts,2áoz.)

Mixed vegetables (kinds specified on p, 26)

Okra

Peas, green__ ^----

Pumpkin or squash, strained (initial temperature 160 F. )

Summer squash .

Sweertpotatoes in sirup, whole or cut

Time to process at

240° F. (10.3-lb. pressure

at sea level) ^

1 At altitudes above sea level it takes more than 10.3-pound pressure to attain a temperature of 240° F,

gage pressure readings corresponding to 240° at various altitudes.)

Pint Quart

Minutes MiniUes

30 35

30

25 30.

45 50

35 40

30 35

105

60 70

85 105

45 50

30 35

45 50

85 125

35 45

55 65

ture of 240° F. (See table 3 for

PROCEDURE FOR CANNING MEAT AND POUtTIÉY

The procedures for preparing and processing meats

and poultry are briefly outlined in table 8,

The instructions given for roasts, steaks; stew

meat, and ground meat may be used for beef, veal,

mutton, lamb, pork, and large game animals.

Similarly, the instructions given for chicken may be

used for duck, goose, guinea, squab, turkey, or

small game animals such as rabbit.

Can the meaty pieces of chicken or other poultry,

with or without the bone. Use the bony pieces for

soup stock. Giblets may be canned also but because of their flavor, should be canned separately.

When canning meat, bone out the carcass and

separate the tender from the less tender cuts. Trim

the meat to remove tough connective tissue, blood

clots, and most of the fat. Cut the large tender

pieces to fit into pint or quart jars, with the gram

of the meat running lengthwise. Use the less

tender cuts and good quahty trimmings for stew

meat and ground meat. Do not use meat of doubtful

freshness or lumps of fat. Use the bones for making

soup stock.

Meat and poultry may be canned with or without

salt. If they are canned with salt, use a good-grade

canners' salt and put it in the jar before packing the

meat. For ground meat, however, add the salt

to the meat and mix well before grinding.

Roasts, steaks, stew meat, and chicken may be

precooked and packed hot or be packed raw and

exhausted to 170° F. before seahng. Other meats

and soup stock are packed hot. Follow carefully

the instructions given for preparing each product.

Work fast. Seal and process the jars before they

cool to any extent. Otherwise, the processing times

will not be adequate.

27
TABLE 8.—Time and temperature for processing meats and poultry in glass jars that are to he spray-cooled

Meats

Roasts, steaks, _-

and stew meat

Ground meat, cakes.

Sausage, cakes or_

links.

Heart and tongue.

Corned beefChicken with bone.

Chicken withoutbone

Preparation steps

Hot Pack—Precook meat slowly in just enough water to prevent sticking. Cook

until medium done or until meat has a pink, rather than red, color at center.

Pack hot into jars to within 1 inch of top. Cover with hot meat juice or broth

leaving 1-inch head space in jars. Seal and process immediately.

Raw Pack—Pack pieces of raw meat firmly into jars to within 1 inch of top. Do

not add liquid. Exhaust for 75 minutes or until center-jar temperature is 170°

F. Press meat down into jars and add boiling broth, if needed, to cover the

meat, leaving 1 inch head space. Seal and process immediately.

Form ground meat into fairly thin cakes to fit glass jars. Precook cakes until

red color at center is almost gone. Pack hot into jars to within 1 inch of top.

Add hot broth or meat drippings from which fat has been removed to completely

cover the meat. Shake jars to distribute liquid. Add more liquid, if necessary,

leaving 1 inch head space in top of jars. Seal and process immediately.

WARNING—These processing times will not be adequate for raw, solid-pack ground

meat.

Use any tested sausage recipe but omit sage and go easy with other spices, onion,

and garlic because flavors change with processing and storing. Shape sausage

meat into cakes or fill into sausage casings and tie in links to fit the length of

jar, allowing about 1 inch head space. Precook cakes or links until pink color

at center is almost gone. Pack hot into jars to within 1 inch of top—

cakes in layers; links on end. Cover with boiling water or drippings from

which fat has been removed. Shake jars to distribute the liquid. Add more

liquid if necessary, leaving 1-inch head space in top of jar. Seal and process

immediately.

Prepare heart and tongue separately for canning. To prepare heart,, wash

thoroughly. Remove thick connective tissues and cut into pieces. Simmer

until medium done in just enough water to cover. Pack hot into jars to

within 1 inch of top. Cover with boiling broth leaving 1-inch head space.

Seal and process immediately. To prepare tongue, wash thoroughly. Cover

with boiling water and simmer until skin can be removed. Then cut into

pieces and proceed as for heart.

Wash corned beef. Cut into pieces suitable for packing in jars. Cover meat

with cold water and bring to a boil. If broth tastes very salty, drain and

cover with fresh water and parboil again. Pack hot meat into jars to within

1 inch of top. Cover with hot broth leaving 1 inch head space. Seal jars

and process immediately.

Hot Pack—Use meaty pieces. Bone breast, saw drumsticks off short, if desired.

Leave bone in second joint. Precook chicken until medium done in just enough

water to cover meat. Pack hot into jars to within 1 inch of top. Pack second

joints and drumsticks so that skin is next to glass. Fit breasts and smaller

pieces into center. Cover with boiling broth skimmed of fat, leaving 1-inch

head space. Seal jars and process immediately.

Raw Pack—Pack pieces of raw chicken firmly into jars to within 1 inch of top.

Pack second joints and drumsticks so that skin is next to glass. Fit breasts and

smaller pieces into center. Do not add liquids. Exhaust for 75 minutes or

until center-jar temperature is 170° F. Press chicken down into jars. Add

boüing broth, skimmed of fat, if needed to cover the meat, leaving 1 inch

head space. Seal jars and process immediately.

Remove bone from meaty pieces of chicken either while raw or after precooking.

Then follow directions given for canning chicken with bone by hot pack or raw

pack method but process for the longer time required. Chicken without bone

is more solidly packed than chicken with bone and therefore must be processed longer.

Time to process

at 240° F. (10.3-

Ib. pressure at

sea level) ^

Min.

90

90

90

90

90

90

80

80

90

Min.

105

105

105

105

lOô

lOf

90

90

105

See footnote at end of table.

28
TABLE 8—Time and temperature for processing meats and poultry in glass jars that are to he spray-cooledContinued

Meats Preparation steps

Time to process

at 240° F. (10.3-

Ib. pressure at

sea level) i

Pint Quart

Chicken giblets

Soup stock

Because of their flavor it is best to can Uvers alone. Gizzards and hearts may be

canned together. Cook the giblets in broth made from bony pieces of chicken

or in water until medium done. Pack hot into jars to within 1 inch of top,.

Cover with hot broth skimmed of fat leaving 1 inch head space. Seal jars and

process immediately.

Use bony pieces of chicken or other bony pieces of meat. Saw large bones, such

as beef bones, in suitable lengths to fit into steam-jacketed kettle or stock pot.

Partially cover with lightly salted water and cook until meat is tender. Remove

pieces of bone and trim off meat. Skim fat off broth. Add meat to broth and

heat mixture to boiling. Fill hot into jars to within 1 inch of top, stirring

the mixture each time a jar is filled. Seal jars and process immediately.

Min.

90

45

Min.

105

60

^ At altitudes above sea level it takes more than 10.3-pound pressure to attain a temperature of 240° F.

gage pressure readings corresponding to 240° at various altitides.)

(See table 3 for

TABLE 9.—Summary of time and temperature for processing meats and poultry in glass jars that are to he spraycooled

Meats

Time to process at

240° F. (10.3-lb. pressure

at sea^^d^^

Pint Quart

Roasts, steaks, and stew meat:

Hot pack

Raw pack (exhaust to 170° F.)

Ground meat, cakes_

Sausage, cakes or links _

Heart and tongue

Corned beef

Chicken with bone:

Hot pack

Raw pack (exhaust to 170° F.)

Chicken without bone:

Hot pack

Raw pack (exhaust to 170° F.)

Chicken giblets

Soup stock

Minutes Minutes

90

90

90

90

90

90

80

80

90

90

90

45

105

105

105

105

105

105

90

90

105

105

105

50

1 At altitudes above sea level it takes more than 10.3-pound pressure to attain a temperature of 240° F. (See table 3 for

gage pressure readings corresponding to 240° at various altitudes.)

-^U. S. GOVERNMENT PRINTING OFFICE: 1952 ^212370

29