Canning at High Altitudes

In most home canning recipes, recommended processing times for boiling water and pressure canners are stated for use at elevations of 0 (sea level) to 1,000 ft (305 m). Because air is thinner at higher elevations, water boils at temperatures lower than 212°F (100°C) and pressure levels are reached at lower temperatures. Lower temperatures are less effective in destroying microorganisms, so adjustments must be made to assure the safety of home canned foods preserved at higher altitudes.

When using a boiling water canner at altitudes higher than 1,000 ft (305 m), processing times must be extended.

Boiling Water Canner- Altitude Adjustments

1,001 - 3,000 306 - 915 5 minutes
3,001 - 6,000 916 - 1,830 10 minutes
6,001 - 8,000 1,831 - 2,440 15 minutes
8,000 - 10,000 2,441 - 3,050 20 minutes

When using a pressure canner at altitudes above 1,000 ft (305 m), the pressure level is increased but the recommended processing time remains constant. The type of pressure canner used determines the pressure adjustment.

Weighted Gauge Pressure Canner- Altitude Adjustments

1,000 0 - 305 10 69
1,001 - 2,000 306 - 609 15 103
2,001 - 4,000 610 - 1,219 15 103
4,001 - 6,000 1,220 - 1,828 15 103
6,001 - 8,000 1,829 - 2438 15 103
8,001 - 10,000 2,439 - 3,048 15 103

Dial Gauge Pressure Canner- Altitude Adjustments

0 – 1,000 0 - 305 11 76
1,001 – 2,000 306 - 609 11 76
2,001 - 4,000 610 - 1,219 12 83
4,001 - 6,000 1,220 - 1,828 13 90
6,001 - 8,000 1,829 - 2438 14 97
8,001 - 10,000 2,439 - 3,048 15 103

< Back to TOP

How do I determine the altitude of my home?

Most local elevations or "altitude" can be determined by looking at a local map. Or, refer to the chart below. If you are not able to find data for your particular location, call Bernardin Ltd. toll free at 1-888-430-4231. One of our customer service representatives will be happy to assist you.









British Columbia       Alberta    
Prince George
Medicine Hat
Red Deer
Saskatchewan       New Brunswick    
Swift Current
St. John
Manitoba       NWTerritories    
Ontario       Quebec    
North Bay
Sault Ste. Marie
Thunder Bay
Quebec City
Nova Scotia       Nunavut    
Halifax 477 145   Iqaluit 110 34
P.E.I.       Newfoundland    
Charlottetown 160 49   St. John's 461 141
Yukon Territory            





< Back to TOP

Can fruit be safely canned without adding sugar?

Sugar is not an "essential" ingredient for safe preservation of food in mason jars. Many foods can be safely preserved with little or no added sugar. The absence of sugar, however, may alter the flavour, texture and colour of home preserved foods especially when compared to similar foods that contain higher quantities of sugar.

To preserve fruit without sugar, select only fully ripe fruit at its peak flavour. Water or unsweetened fruit juice (such as white grape or apple juice) may be used in place of sugar syrup. Or, if you choose, make a Very Light Syrup: combine 1/2 cup (125 ml) granulated sugar with 5 cups (1250 ml) water. This approximates the natural sugar level in most fruits and adds few calories. This small quantity of sugar also helps canned fruit retain their natural colour and texture.

< Back to TOP

Can I buy mason jars by mail order? (i.e. Order Online)

Due to the special handling and high postage costs required to deliver cases of glass jars without breakage, Bernardin mason jars are not offered in our mail order selection. Selected mass merchandisers, hardware and grocery stores across Canada, sell a selection of BERNARDIN® Mason Jars year-round. If you don't see them in the store, ask the store manager. If the item is listed in the store's central warehouse, the manager can order it in for you.

Four-packs of BERNARDIN® Collection Elite® mason jar storage pots and lids are available in the Order OnLine section of the website.

< Back to TOP

Can I reuse SNAP LID® that have been heated in hot water?

Yes, if you've prepared more lids than are required for a specific recipe, remove the extra SNAP LID® from the water and dry with a towel. Store in a dry spot until ready to use again. For your next canning project, re-heat these unused SNAP LID® as directed in hot water.

< Back to TOP

Can vegetables be canned safely without adding salt?

Yes, vegetables can be home canned safely without salt. The measured quantity of salt indicated in most recipes is intended for taste and seasoning. The quantity is too small to control food spoilage. If desired, simply omit salt or reduce to taste. Do not omit or reduce salt from pickled foods or seafood. 

< Back to TOP

Do you have a home canning recipe for ________?

Search for home canning recipes by clicking RECIPE SEARCH. Then type the recipe name or main ingredient in the Keywords field and click "Find It!"


If this search does not identify the recipe you seek, type your request in the Message field of the Contact Us form. Be sure to give us your name and address so that we can reply promptly to your request.

< Back to TOP

Does Bernardin have a factory outlet store?

No, Bernardin does not operate a factory outlet store. Direct sales to consumers are not made at the company´s headquarters in Toronto.


Grocery and general merchandise stores across Canada continue to be the most cost efficient source of Bernardin home canning products. We recognise, however, that retailers limited display space makes some of our products difficult to locate in some areas, year-round. Thus a selection of home canning supplies and accessories are available via mail order. Clicking ORDER ONLINE presents this selecton.

< Back to TOP

How can I purchase Bernardin products wholesale for my business?

Bernardin distributes its products in Canada via retailers and distributors. We do sell to a limited number of individual businesses that meet our minimum purchase requirements. If you operate a business that uses a substantial quantity of mason jars, lids or fruit pectin annually, please use the contact form to email us. Be sure to complete all of the contact information listed below and answer all the following questions in your message.

  1. What type of business? i.e. home-business (products are sold after filling); formal-business (products are sold after filling); OR distributor (products resold as received)
  2. What products are required? (i.e. size of jar, etc.)
  3. What do you think your annual volume requirement would be? (i.e. number of jars, lids, quantity of fruit pectin, other home canning products)
  4. How much product would you purchase with each order?


Our sales department will evaluate and respond to all requests. If your projected annual volume is not large enough to meet our minimum shipment requirements, we will attempt to assist you in locating a distributor in your area.

< Back to TOP

How do different canning methods effect the safety of home canned foods?

There are no safe short-cuts in home canning. Heat processing all high acid foods in a boiling water canner and low acid foods in a pressure canner--for the appropriate time for the food and jar size--are the only currently approved methods for safe home canning.

There is no substitute for adequate heat treatment. Some people may experience "good luck" with outdated methods...and then one year everything spoils! Each growing season is different. Heat-resistant bacteria are not necessarily present in every piece of produce. IF these organisms are absent...and that's a big IF...under-processed foods might keep. When they are present, the food spoils. Be safe rather than sorry. Always assume these microorganisms are present. Follow current, tested practices, such as those recommended on this site, that use the equipment and supplies available to you today.

Certain home canning methods and techniques, once thought to offer success, have been shown to be faulty, unsafe and potentially dangerous. These include:


Due to their high failure rate, the use of jars that utilize glass caps and rubber rings are not recommended for safe home canning today. Reference: Complete Guide to Home Canning and Preserving, Second Revised Edition, U.S. Department of Agriculture, 1999, p 10 and 11. This publication further states the same with regard to jars with wire bails and glass caps, one-piece zinc porcelain lined caps and flat rubber rings.


Paraffin wax is NOT recommended for safe food preservation for a number of reasons.

NOTE: Paraffin wax is a flammable material that can be dangerous, especially when handled by inexperienced cooks.

Melted paraffin shrinks as it solidifies. Liquefied paraffin covers soft spreads spreading to the jar rim, but as it cools and hardens, paraffin shrinks away from the glass enough to allow air to come in contact with the food leading to the development of molds. Although it may appear to be solid, hardened paraffin wax can have microscopic pinholes running through it. Thus air can come in contact with the food, which can lead to the development of molds.

It was once presumed that mold growth on jellied products could be removed (skimmed off) and the product below would be safe to eat. However, research has shown that mold growth may produce mycotoxins, that can be very harmful to human health. Mycotoxins can migrate like invisible threads through the food to the bottom of the jar. Thus, skimming the surface mold will not remove mycotoxins.

The only safe way to eliminate or prevent mycotoxins is to place freshly-made soft spreads in mason jars with Bernardin two-piece home canning SNAP LID® closures followed by heat processing for the recommended method and time for the product and jar size. Heat processing vents air from the headspace, heats container and contents to inactivate food spoilage organisms and creates an airtight vacuum seal as the product cools


Open-kettle canning is not safe and is not recommended for food preservation. Open-kettle canning involves cooking the food in an open saucepan. The hot food is then put into jars and the lids are quickly put in place. This method "hopes" that a proper seal will be achieved as the food cools.

Regardless of the duration or heat intensity of the cooking period, the open-kettle method is not safe because the filled jars of food are not heated to and maintained at temperatures necessary to destroy spoilage microorganisms and assure strong vacuum seals. The open-kettle method omits essential heat processing necessary to drive the air from the jar to create a vacuum seal. The lid may appear to seal, but later may unseal due to a low vacuum. Or, microorganisms left in the food may cause spoilage. This spoilage produces gases, which in turn increase pressure inside the jar. The increased pressure may force the lid to release.

Foods ferment when open-kettle canning does not destroy yeasts, or permits them to enter the jar as it is filled and before it is sealed. Simply getting lids to curve downward on jars will not, in itself, prevent food from spoiling. The only successful way to create an airtight vacuum seal and destroy spoilage microorganisms is to heat process all filled jars by a method and time, appropriate for the type of food and jar size.


Not only is it unsafe, oven-canning can be extremely hazardous. Regardless of the brand of oven, jar, cap or lid you use, jars can break or explode due to temperature fluctuations when the oven door is opened. When you preserve food, it is important to know and control temperature. Oven temperatures vary according to accuracy of the oven regulator and how heat circulates. Also, dry heat penetrates food jars very slowly. Moreover, the temperature of the food inside the jar is not heated sufficiently to destroy microorganisms.

Do not confuse steam canning with pressure canning. Steam canning places jars of food on a rack in a covered, shallow pan. As the water in the shallow pan boils, steam is circulated around the filled jars. Steam in this device is not pressurized. These canners do not create a steady flow of steam nor maintain an even temperature. It is impossible to know if the heat has penetrated the food properly. The heat processing times given in recipes on this site are safe for processing foods in a boiling water canner or pressure canner as specified. Do not use these processing times for a steam canner as safe processing times have not been established for this method.

< Back to TOP

What are the Outdated Techniques?

Up-to-date lid application technique is important!

Changes in lid design and sealing compounds have led to new and improved application techniques for ensuring tight seals to guard against food spoilage.

In years past, instructions for zinc lids as well as metal bands, used with rubber rings and glass lids, dictated that lids be twisted on very tightly or be applied very firmly and then backed off (reversed) a quarter turn.

Other out-dated techniques required that bands be retightened after processing or that jars be inverted after closing or processing.

All of these lid application techniques are outdated! Used with today's two-piece metal lids, these techniques can cause seal failure. These outdated techniques simply do not work successfully with two-piece metal home canning lids made and sold in Canada and the United States.Always follow the manufacturer's recommendations for use of a product.

  • Blanket Steeping: Heating filled jars of food in boiling water and then wrapping the jars in woolen blankets to keep them warm over a period of time is not recommended for any type of food. Food preserved according to this method of food preservation rarely, if ever, reaches temperatures sufficient to destroy microorganisms. Keeping the jars warm in blankets can, in fact, be dangerous. The prolonged warm environment may promote bacterial growth inside the jars.
  • Grandmother's Recipes: General home canning guidelines were updated in the late 1980s to meet today's standards of quality and safety. Home canning recipes or books published prior to 1988, may contain outdated information which could affect the safety of the end result. For this reason, we suggest using a reputable canning guide published after 1989.
  • Microwave Canning: Potentially unsafe devices have been marketed for canning food in a microwave oven. These devices have not been shown to destroy all bacteria present in the food nor do they heat uniformly. Problems may also occur with food siphoning out of the jars and lid failures. Do not use these devices to can food at home.
  • Vacuum Sealing Devices: Some kitchen appliances can create a vacuum in a mason jar without heat treatment. Since there is no heat treatment to destroy spoilage microorganisms and botulism bacteria, these organisms can grow under the vacuum seal. Vacuum sealing devices are not safe substitutes for proper heat processing in mason jars. If you wish to use vacuum sealers with canning jars, use them only for dry ingredients and non-perishable staples.

< Back to TOP

What are the Instructions for Heat Processing?

Foods are divided into two groups when home canning: High Acid and Low Acid. This is due to the different types of spoilage micro-organisms they may contain. Each group requires a specific heat processing method to effectively destroy these micro-organisms and avoid spoilage while filled jars are in storage.

  • High Acid Foods: jams, jellies, fruits, tomatoes with added acid, pickled products including dill pickles, relishes and chutneys.
  • Low Acid Foods: vegetables, meat, poultry, game, seafood, tomatoes without added acid and most tomato-based products such as spaghetti sauces.

High Acid Foods:
These foods require the temperature of boiling water (212ºF/100ºC) to destroy yeast and mould. This is done in a boiling water canner with a rack on the bottom. Cover the filled jars with 1 to 2 inches (2 to 5 cm) water and bring to a boil. Start timing the heat processing only when water boils. Times vary depending on jar size, food density and chemical make-up. Never use a recipe that does not specify a heat processing time.

Low Acid Foods:

These foods require a temperature of 240ºF (116ºC) to destroy harmful bacteria such as Clostridium botulinum (Botulism). This temperature, higher than that of boiling water, can only be achieved in home kitchens with a pressure canner. Boiling water alone is not enough to kill bacteria that live in low acid food, and will actually promote its growth. Never use a recipe for low acid food that does not give instructions on how to heat process in a pressure canner. Also, refer to your pressure canner instruction manual.

*Only use home canning recipes from reliable sources, such as Bernardin. Never use a recipe that does not give a heat processing time and method for the food that you are preserving.

< Back to TOP

How do I fix a jam or jelly that didn't gel?

Unique circumstances regarding the growing season, the fruit variety or the fruit itself occasionally necessitate more than 24 hours for a gel to form. Therefore, wait two weeks to see if the product will gel. Do not disturb or shake the product during this time.

If after two weeks the product still has not gelled, it may be recooked. Keep these factors in mind when deciding to recook a fruit spread.

  • Only remake products that have maintained a good seal.
  • First, make one trial batch using 1 cup (250 ml) unset product to assure success.
  • Do not recook more than 8 cups (2000 ml) at one time.
  • All remade jams and jellies must be processed in a boiling-water canner.
  • Heat SNAP LID® sealing discs in hot water, not boiling (180°F/82°C). Keep jars and sealing discs hot until ready to use.

< Back to TOP

How to Remake cooked jam/jelly using powdered fruit pectin

1) Measure unset jam/jelly to be remade.

2) For each 1 cup (250 ml) product, measure:
  • 2 tbsp (30 ml) granulated sugar,
  • 1 tbsp (15 ml) water and
  • 1  tsp (7 ml) BERNARDIN® Fruit Pectin.
3) In a large, deep stainless steel saucepan, whisk fruit pectin into water. Stirring constantly to prevent scorching, bring to a boil. Stir in the measured jam and sugar.

4) Stirring constantly over high heat, bring to a full rolling boil; boil hard 30 seconds. Remove from heat; skim foam, if necessary.

5) Ladle into hot sterilized jars, leaving 1/4 inch (0.5 cm) headspace. Remove air bubbles. Wipe jar rim removing any stickiness. Centre new SNAP LIDS® on jars; apply screw bands securely until fingertip tight. Heat process 10 minutes in boiling water canner.

< Back to TOP

How to Remake cooked jam/jelly using liquid pectin

1) Measure unset product and place in a large, deep stainless steel saucepan.

2) For each 1 cup (250 ml) unset product, measure and set aside:

  • 3 tbsp (45 ml) granulated sugar,
  • 1 tsp (7 ml) lemon juice
  • 1 tsp (7 ml) BERNARDIN® Liquid Pectin

3) Stirring constantly over high heat, bring product to a boil. Add sugar, lemon juice and liquid pectin.

4) Stirring constantly, return mixture to a full rolling boil; boil hard 1 minute. Remove from heat; skim foam, if necessary.

5) Ladle into hot sterilized jars, leaving 1/4 inch (0.5 cm) headspace. Remove air bubbles. Wipe jar rim removing any stickiness. Centre new SNAP LID® on jar; apply screw band securely until fingertip tight. Process 10 minutes in boiling water canner.


< Back to TOP

How do I know if a home canning recipe from friends/family is safe to use?

Be sure the recipe complies with up-to-date guidelines that include proper heat processing of all filled jars using the appropriate method and time for the type of food, jars and lids available today.

Home canning books or recipes considered to be family heirlooms or treasures, may not always be safe to use. In 1989, the United States Department of Agriculture (USDA) updated their home canning guidelines based on safety and quality. Therefore, a home canning book or recipe that was published before 1989 may be outdated and could affect the safety and quality of your home canned foods.

The BERNARDIN® Guide to Home Preserving, BERNARDIN® Complete Book on Home Preserving as well as other books available in the Reference Library of Order OnLine offer up-to-date information and recipes.

< Back to TOP

How do I know if a jar of home canned food is spoiled?

When up-to-date guidelines, such as those outlined on this site, are followed exactly, there should be little concern about the quality and safety of your home canned foods. As with commercial packaged foods, it is always wise to examine any food before using it. When you take it from the shelf, check each jar to see that it has retained its seal and that no visible changes have taken place during storage.

Unsealed lids indicate the possibility of spoilage. Certain spoilage microorganisms, such as yeast, produce gases that increase the pressure inside the jar. This increased pressure can break the seals and/or cause the lids to swell. If a lid can be removed without the use of pressure, do not use the product.

Other signs of spoilage include mold, bubbling gases, cloudiness, spurting liquid upon opening, seepage, yeast growth, fermentation, sliminess or disagreeable odors. If you know that a low acid food was improperly processed (i.e. in a boiling water canner as opposed to a pressure canner) do not use it under any conditions.

If you suspect spoilage, dispose of the food without tasting it ,when in doubt, throw it out.  Dispose of all spoiled foods in a manner that will prevent consumption by humans or animals.

< Back to TOP

How do I prepare my mason jars and SNAP LID® prior to use?

Visually inspect mason jars for nicks, cracks, uneven rims or sharp edges that may prevent sealing or cause breakage. Check screw bands for proper fit on your mason jars and be sure SNAP LID® are new (previously unused) and scratch-free.

Wash jars and lids in hot, soapy water; rinse well. Place required number of clean mason jars on a rack in a canner or large saucepan.

  • If using a boiling water canner; cover jars with water and heat water to a simmer (180°F/82°C). Keep jars hot until used.
  • If using a pressure canner, place clean jars in canner, add water to 3-inch depth (7.5 cm) and heat to a simmer (180°F/82°C), Leave jars in hot water until used.

(Note, if packing jars with chilled fish, do not preheat jars or water prior to filling jars. When mason jars are filled and pressure canner is filled, add room temperature water to depth recommended by pressure canner manufacturer.)

Heat processing time recommendations for jams and jellies was been increased from 5 minutes to 10 minutes in 2003, thus eliminating the need to pre-sterilize mason jars before filling. Tests have shown that increasing the processing time does not adversely affect the product. If you choose to continue to use high acid recipes that require less than 10 minutes heat processing time, mason jars should be boiled 10 minutes, at altitudes up to 1,000 ft (305 m), prior to filling and the subsequent shorter than 10-minute heat processing time.

"Boiling lids" prior to placement on jars is no longer required for home canning. This recommendation has been changed to "Bring SNAP LID® to a boal and leave in hot water until ready to use. In the past, the recommendation was to "boil SNAP LIDS® five minutes" before placing them on filled jars. Extensive testing by Bernardin's technologists revealed that boiling the lids too long, combined with overly tight application of the screw bands could lead to seal failure. SNAP LID® must be hot when placed on hot jars of hot food, whereas screw bands should be room temperature. Tighten screw bands securely & firmly until resistance is met - don't overtighten. Heat processing ALL filled jars is still a necessity for safe home canned foods.

Screw bands require no preparation and are much easier to handle if left at room temperature. Apply screw bands evenly and firmly until resistance is met. Don't overtighten as this prevents venting - air escaping - during heat processing.

* Heat processing all filled jars is still a necessity for safe home canning.

< Back to TOP

How do I prevent browning in light colour fruits?

Fruit-Fresh® Fruit Protector helps retain fruit's natural colour and flavour and can be used for fresh fruit, canning and freezing. It is most commonly used for light fleshed fruit, such as peaches, pears and apples.

Fruit-Fresh® Fruit Protector contains ascorbic acid  an antioxidant (a source of Vitamin C) and dextrose, a natural sugar. They increase acidity and pull juice to fruit's surface retarding browning and flavour loss.

Dissolve 1 tbsp (15 ml) Fruit-Fresh® Fruit Protector in 3 tbsp (45 ml) water. Toss with 4 cups (1000 ml) fruit; drain & serve. Or, mix 1 part Fruit-Fresh® Fruit Protector with 8 parts sugar. Toss with fruit; chill & serve. If desired, Fruit-Fresh® Fruit Protector may also be sprinkled over cut fruit which is then lightly tossed to distribute natural juices.

As it is prepared, place cut fruit into a solution of 4 tbsp (60 ml) Fruit-Fresh® Fruit Protector dissolved in 8 cups (2000 ml) water. Drain fruit. Raw Pack: Pack fruit into a hot jar. Hot Pack: Combine fruit & canning syrup, bring to a boil. Pack hot fruit into hot jar. Next step for both Raw Pack and Hot Pack -- cover fruit with boiling canning syrup* leaving 1/2 inch (1 cm) headspace. Remove air bubbles. Centre SNAP LID® on jar, apply screw band until fingertip tight. Process in a boiling water canner for time required for type of fruit and jar size.

Option 1:
Sprinkle prepared fruit liberally with Fruit-Fresh® Fruit Protector and place on single layer on cookie sheet. Place in freezer until solid, about 35 minutes. Transfer frozen truit to freezer bags or container squeezing out excess air.

Option 2:
As fruit is prepared, place it in a solution of 4 tbsp (60 ml) Fruit-Fresh® Fruit Protector dissolved in 8 cups (2000 ml) water. Drain fruit. Pack fruit tightly into freezer containers; cover with chilled syrup* leaving 1/2 inch (1 cm) headspace. Place crumpled waxed paper on fruit to push it under syrup. Seal & freeze.

*CANNING SYRUP: Boil 4 cups (1000 ml) water with sugar for desired type, 5 minutes. Then add 2 tsp (10 ml) Fruit-Fresh® Fruit Protector per 1 cup (250 ml) syrup. Use medium syrup for most fruit. For pears, use light syrup with 1 tbsp (15 ml) Fruit-Fresh® Fruit Protector per 1 cup (250 ml) syrup.

Light - 11/4 cups (300 ml) sugar plus 4 cups (1 L) water yields approximately 5 cups (1250 ml) light syrup.

Medium - 3 cups (750 ml) sugar plus 4 cups (1 L) water yields approximately 5 1/2 cups (1375 ml) medium syrup.

Heavy - 4 3/4 cups (1175 ml) sugar plus 4 cups (1 L) water yields approximately 6 1/2 cups (1625 ml) heavy syrup.

< Back to TOP

How do I reduce the quantity of sugar in jam or jelly recipes?

When preparing jams or jellies with dry or liquid fruit pectins, reducing the quantity of sugar from that recommended in the recipe can cause gel failure. Consumers with special dietary needs may wish to use a special product, BERNARDIN® No Sugar Needed Fruit Pectin, which gels fruit mixtures with no added sugar. Such fruit spreads are sweetened exclusively by fruit's natural sweetness. The sweetness of fruit spreads made with this No Sugar Needed pectin can be enhanced with artificial sweeteners or a small quantity of corn syrup, honey or up to 3 cups of granulated sugar.

The quantity of sugar in a long boil jam recipe may be reduced at the maker's discretion. However, the product will need to be cooked longer to reduce liquids and concentrate the natural sugars from the fruit used. In many cases, this lengthened cooking will result in a product with a carmelized flavour and considerably lower yield than similar quantities of fruit prepared with added pectin. Although long boil fruit spread recipes appear to use less sugar, by the time they are cooked down the sugar concentration is likely to be very close to added-pectin recipes that start with a greater quantity of added sugar.

Jellies require a delicate balance of sugar, fruit juice and acid. For ultimate jelly-making success, start with a tried and true jelly recipe and use ingredients in the specified quantities.

< Back to TOP

How long can home canned foods be stored?

Jars of food that have been properly heat processed and have an an intact vacuum seal will keep indefinitely. However, changes do occur during shelf storage. These changes may affect the flavour, colour, texture and nutritional value of the product. Therefore, for best results, we recommend using home canned food within one year.

< Back to TOP

How tightly should screw bands be applied?

Apply screw bands securely until fingertip tight. Center the prepared SNAP LID® on the jar. Then, using just your fingers, screw the band down evenly until you meet a point of resistance. Do not overtighten bands by using the full force of your hand or a utensil to tighten the band. 

After processing, bands may appear to have loosened. This is natural. Do not retighten bands after processing. Let jars stand undisturbed 24 hours.

Overtightening bands prevents venting of excess air from the jar during heat processing. Jars that do not vent properly do not seal securely. Screw bands that are applied too tightly can cause lids to buckle. Buckling leads to seal failure.

< Back to TOP

I cannot find a certain Bernardin product. Can you help me?

Home canning supplies are sold at most grocery stores, hardware stores and in mass merchandise outlets across Canada. Unfortunately, not every store stocks every product year-round. The most abundant selection of home canning supplies is found in these stores during the spring-summer harvest seasons. Certain national and regional mass merchandisers, food chains and hardware stores carry a selection of home canning items year-round. If you do not see the item you want on the shelf, ask the store manager. If the item is listed in the store's general warehouse, managers can order the product in for you.   The most common stores to find our products year round are Canadian Tire, Wal-Mart, Zellers and Home Hardware.  Please ask for assistance if your unable to find what you are looking for. 

< Back to TOP

If home canned foods have frozen during storage, are they safe to eat?

If the jar of food was processed according to current home canning recommendations , and the jar is still vacuum sealed, the food should be safe to eat. Examine the jar closely, freezing can cause damage to the vacuum seal or jar breakage. Home canned food that has been frozen during storage may by less desirable due to changes in texture, flavour, nutritional value and colour.

< Back to TOP

Must all jars of home canned foods be heat processed?

Yes, all jars of home canned foods that will be stored at room temperature must be heat processed to assure shelf stability and food safety. There are only two methods for heat processing home canned foods that are considered safe: boiling water canner for high acid foods and pressure canner for low acid foods. More detailed information on heat processing is found in Canning Basics and Step-by-Step.

< Back to TOP

My inquiry doesn't fit any of the available categories.

If your query doesn't fit any of the above categories and/or if your review of available FAQs has not answered your question to your satisfaction, please use the message field to forward that inquiry to Bernardin. Our Consumer Response staff will attempt to assist you.

< Back to TOP

What causes colour changes in home canned foods?

Although it may not be appetizing, you can eat most discoloured home canned food if the liquid is clear, the odour natural, and if you know the canning was done properly with recommended heat processing methods, time and temperature. The most frequent causes of colour change in home canned foods can be traced to:

  • Harvesting and handling- To maintain the most natural colour possible, keep all fruits and vegetables cool from the time they are harvested until they are canned. When hot-pack canning, do not overcook or heat produce at too high a temperature. Excessive heat alters virtually all natural food pigments.
  • Weather- Fruit that grows in very dry, hot weather, frequently turns pink when canned. This colour change cannot be prevented.
  • Oxidation- Light coloured fruits such as peaches and pears turn brown when exposed to oxygen during preparation or in the jar. While preparing fruit place it in a colour protection solution -- 4 tbsp (60 ml) Fruit-Fresh® dissolved in 8 cups (2 L) water. Be sure to remove air bubbles before closing the jar and pack fruit so that it will not float above the level of the syrup at the top of the jar.
  • Low sugar foods lose some colour when canned because sugar helps stablize the colour. Colour intensity is greatest in full sugar jams and fruits canned in sugar syrups. True reds are more difficult to maintain in reduced sugar spreads.
  • Improper storage conditions may also cause colour changes. Store canned foods in a cool, dark place.

Pink-purple cauliflower
- Some cauliflower varieties are genetically inclined toward higher concentrations of red, purple, or blue pigments. This is the same harmless, water soluble pigment found in eggplant, red cabbage, berries, plums and grapes. In other types of cauliflower colorless or white pigments predominate. Purpling can develop in white varieties of cauliflower when heads are exposed to light during their growth. Tying leaves over the heads prevents light exposure. Purple cauliflower is safe to eat. If the purpling is excessive, use the vegetable raw for relishes or salads. Heat may induce a color change from purple to gray or slate blue--especially if the water is hard or has an alkaline pH. If you must cook purplish cauliflower, add a little vinegar or cream of tartar (tartaric acid) to the water.

Pale beets:
Red pigments fade when the beets are overcooked before canning or overprocessed during canning. To minimize colour loss, always leave a portion of the stem and the taproot intact when cooking beets.

Green, blue garlic :
  Immature garlic that has not been properly cured for 2 to 4 weeks at 70°F can turn an iridescent greenish color in cooked foods. Some varieties of garlic and/or growing conditions produce garlic that has an excess of natural bluish pigmentation. This colouring is more evident after pickling. Garlic colour changes can also be caused by a reaction between its natural pigments and iron, tin or aluminum in your cooking utensils or water.

  Always use pickling salt. Avoid using sea salt as it contains minerals from the sea that can affect the colour of pickles.

< Back to TOP

Jar and Lid Prep

Preliminary: Visually inspect mason jars for nicks, cracks, uneven rims or sharp edges that may prevent sealing or cause breakage. Do not use these jars. Check screw bands for proper fit on your mason jars and be sure the enamel surface of SNAP LIDS® closure is scratch-free. Wash jars and lids in hot, soapy water; rinse well.

Canning: Place clean mason jars on a rack in a boiling water canner; cover jars with water and heat to a simmer (180°F/82°C). Keep hot until use. Set screw bands aside; heat lids in hot water, not boiling (180°F/82°C). Keep jars and lids hot until ready to use.


  • Screw bands do not have to boiled or heated because they do not come in contact with the food. Screw bands may be re-used. Discard any rusted, scratched or dented bands.
  • SNAP LID® closures are designed for single-use only. Once a seal is formed, the indent in the red plastisol is permanent and may prevent another seal from forming. SNAP LID® closures that were placed in hot water but not needed, may be dried and used for your next canning project.

< Back to TOP

What causes buckled or bulging lids?

Buckled lids appear to warp or bulge upward under the screw bands. There are two causes:

  1. Buckling that is apparent immediately after heat processing is caused by application of the screw bands too tightly. Bernardin two-piece home canning lids are made in two pieces for a very important reason: to release pressure and vent air from the jar during heat processing. As the filled jar is heated, headspace pressure increases until excess air is vented from the jar. When the band is applied too tightly, there is no way for air to be exhausted from the jar. Consequently, the pressure build-up warps the lids and disrupts the seal formation.
  2. Buckling that occurs during storage is caused by food spoilage. When heat processing is insufficient and does not destroy all spoilage microorganisms, food may spoil during storage. This spoilage produces gases inside the jar that forces the lid to bulge upward. This food should be discarded in a manner that neither humans nor animals will consume it.

< Back to TOP

What causes food/liquid to leak out of jars after and/or during heat processing?

Loss of liquid from a jar of food is called "siphoning". It can be caused by:

  • too little headspace
  • failure to keep jars upright at all times
  • removal of jars from processing a boiling water canner too quickly (before boil has subsided)
  • too little water above the jars during boiling water processing
  • fluctuating pressure in a pressure canner.

< Back to TOP

What causes mason jar breakage?

BERNARDIN® mason jars are designed to withstand the repeated heating, cooling and multiple uses associated with home canning. However, they must be handled correctly to avoid certain situations that may result in breakage. The three main causes of accidental jar breakage and preventative measures are outlined below.

1) SCRATCHES: Scratches especially those on the interior surface of mason jars, can weaken the glass and cause breakage when the jars are heated or handled. Scratches are caused by:
  • Metal utensils used to remove food from jars
  • Knifing out air bubbles using a metallic utensil
  • Cleaning jars with steel wool or a wire stem brush
To ensure long lasting durability of your mason jars, clean them with a soft cloth and warm soapy water or in a dishwasher. Only use non-metallic utensils when removing bubbles and serving. Use jar lifters that have a coated surface over the metal.

2) THERMAL SHOCK: Although mason jars can withstand repeated heating and cooling, they are sensitive to quick temperature changes. Sudden cooling or heating can cause thermal shock and result in breakage. These are examples of actions that can thermal shock by:
  • Pouring boiling water or food product into a room temperature jar
  • Placing a room temperature jar into boiling water
  • Setting hot jars on a cool or wet surface
  • Oven sterilization (Jars heat unevenly due to dry heat and temperature fluctuations inside the oven may be too drastic for the jars)
Always put hot food into a hot jar and never place a jar directly into boiling water. Sterilize jars by covering with room temperature water and bringing to a boil. Boil 10 minutes. Place hot jars on a dishtowel or wooden cutting board when filling and cooling.

Heat causes expansion of food and gases inside the jar during processing. Thus pressure builds inside each jar. Glass does not expand, so the pressure needs an outlet. When lids are applied fingertip tight the excess gasses (or pressure) can escape. This action is called "venting". If lids are applied too tightly "venting" is prevented. A build-up of excess pressure inside the jar can cause the jar to break. Apply screw bands fingertip tight, or until they meet a point of resistance. This allows air to escape during processing, properly "venting" the jar.

< Back to TOP

What causes seal failure or lids to seal then unseal?

The use of up-to-date home canning utensils and supplies, following the manufacturer's recommended lid application techniques and heat processing steps are all essential for sealing success with home canning two-piece metal lids.

The most common causes of seal failure are: Insufficient heat processing of filled jars. When filled jars are not heat processed and/or when the heat processing method or time are inadequate for the type of food and jar size, excess air is not vented from the jars and microorganisms that cause food spoilage are not inactivated. Initially, some lids may appear to seal. i.e. curve downward. However, these same lids may unseal during shelf storage. The seal failure at that time is caused by one of two reasons:

1) Very low vacuum was created initially. Low vacuums do not hold over time.

2) Due to inadequate heat processing, food begins to spoil inside the jar. This spoilage produces gases that force the lid to release. All filled jars, regardless of their content, must be heat processed by an appropriate method and time for safe, shelf-stable storage.

  • Over-tightening of screw bands. Overtightening screw bands prevents venting.  Apply screw bands securely, until fingertip tight. Note: Applying screw bands very tightly, then backing them off a quarter turn is an outdated method that does not work successfully with BERNARDIN® SNAP LID®.
  • Re-tightening or tampering with screw bands immediately after processing before food is thoroughly cooled. Allow jars to cool undisturbed for 24 hours.
  • Incorrect headspace or failure to remove air bubbles before placement of the SNAP LID®.
  • Failure to soften sealing compound on SNAP LID® prior to use. Bring SNAP LIDS® to a boil and let stand in hot water until ready to use. 
  • Reuse of single-use SNAP LID® or use of commercial food glass jars.
  • Use of mason jars with nicks, cracks or chips in the sealing edge or neck rim.
  • Failure to clean the rim of the filled jar before applying the lid and/or rapid changes in processing temperatures that cause liquid to siphon from jar. Food, grease or seeds lodged between the jar rim and sealing compound can prevent the formation of airtight seals.
  • Careless or inappropriate handling of jars and lids before and after processing. i.e. inverting jars after filling or processing.

< Back to TOP

What is headspace? Why is it important?

Headspace is the unfilled space in a home canning jar. It is the amount of space between the top of the food or liquid and the underside of the lid (or top edge/rim of the jar). Recommended headspace is based on the jar size and type of food or recipe. The proper headspace provides a good balance of -- enough space for the food to expand during heat processing yet not too much space to allow a strong vaccum to form as the jars cool after processing.

< Back to TOP

What should I do if a lid doesn't seal?

If a lid does not seal within 24 hours, the product must be:

  • Reprocessed immediately
  • Stored in the refrigerator and used within a few days
  • Placed in a proper freezer container and frozen.

To reprocess a product, remove the lid and check the sealing surface of the jar for tiny nicks or imperfections. If glass is damaged, replace the jar. If the product was packed hot originally, empty the jar and reheat the food. Pack the food into a clean, hot jar. (If processing time is less than 10 minutes, sterilize the jar before filling.) Boil a new SNAP LIDS® 5 minutes, place it on the jar and apply the screw band securely, until fingertip tight. Reprocess the product using the canning method and full processing time recommended by an up-to-date reliable home canning resource.

< Back to TOP

Where can I buy gem lids?

Bernardin has reinstated 78 mm Gem SNAP LID® in its line of home canning closures. There are  three sizes of closures  70 mm standard (in red boxes), 86 mm wide mouth (green boxes) or 78 Gem (in yellow-orange boxes).

While lids for gem jars have and are expected to continue to be a very small portion of our overall product offering, Bernardin considers users of these jars in the Western provinces to be valued home canners. Hence, we want owners of 78 mm mouth jars to continue to use proven-quality BERNARDIN® SNAP LID®, if they wish.

< Back to TOP

Where should home canned foods be stored?

Store home canned foods in a cool, dry draft-free place that is as dark as possible.

The best temperature range for home canned food storage is 50° to 70°F (10° to 21°C). Food stored at temperatures higher than 70°F (21°C), may lose some of its nourishing qualities. Freezing can cause the contents of a jar to expand which in turn can break the seal or the jar.

A dark storage area is preferred. Light hastens oxidation and destroys certain vitamins. It can also cause certain foods to fade in colour. Placing jars in cupboards or boxes protects them from light. Avoid damp storage areas as they can cause lids to corrode.

< Back to TOP

Why did my garlic turn blue-green?

Immature garlic that has not been properly cured for 2 to 4 weeks at 70°F can turn an iridescent greenish colour in pickled foods.

Garlic may also turn green when exposed to sunlight or temperature changes. Some varieties of garlic and/or growing conditions produce garlic that has an excess of natural blue/green pigmentation. This colouring becomes more evident after pickling.

Blue garlic colour changes can also be caused by a reaction between garlic's natural sulfur content and copper in water or in iron, tin or aluminum cooking utensils. Blue garlic can also result when sufficient heat is not applied to inactivate garlic's natural enzymes. i.e. pickles that are not sufficiently processed.

In most cases, greenish blue garlic colour changes are not harmful; the product remains safe to eat unless other spoilage signs are present.

< Back to TOP

Why do some pickles lose their crunchy texture?

Factors that can contribute to soft pickles include:

  • Use of vinegar with an acidity level less than 5%
  • Pickles that are not processed or not processed long enough in a boiling water canner to destroy spoilage microorganisms
  • Variety and quality (freshness) of the cucumbers used
  • Improper storage or handling of cucumbers before pickling
  • Cucumbers were not completely covered with liquid when packed in the jar

  1. Brine that was too weak when fermenting cucumbers
  2. Cucumbers not completely covered with brine while fermenting
  3. Scum not removed from top of brine while fermenting
Note: Heat processing does not, in itself, cause soft pickles. Heat processing is essential to create a strong vacuum seal that allows pickles to be stored safely at room temperature.

< Back to TOP

Why must lemon juice or citric acid be added to home canned tomatoes?

Tomatoes have a pH (acid) level that falls close to 4.6 - the line dividing high acid foods and low acid foods. It is important for the safety and quality of all home canned tomato recipes--sauce, whole & halved tomatoes, juice--that a proper acid level is maintained. Since many factors can decrease that natural acidity in tomatoes, the addition of bottled lemon juice or citric acid ensures the correct acidification in each jar. (Bottled lemon juice is recommended because its acid level is consistent, unlike fresh lemons that can have varied levels of acidity.)

Recipes such as salsa, tomato chutney and pickles tomatoes generally include an adequate quantity of vinegar (5% acidity) and do not require additional acidification. Always follow a tested recipe. Do not alter the type of ingredients in the recipe or the quantities used.

< Back to TOP

How do I use a Boiling Water Canner?

A boiling water canner is a large deep pot with a tight fitting lid and a rack to lift jars off direct heat. The pot must be deep enough to cover jars with 1 to 2 inches (3-5 cm) water.

Only high acid foods -- jams, fruits, tomatoes with added acid, pickles (including relish, chutney) -- can be processed safely in a boiling water canner.   

Heating jars in water is the ONLY way to safely sterilise jars and heat process high acid food.
Tip: Turn any large, deep pot into a boiling water canner and tie screw bands together to make a rack.


  • Visually inspect mason jars for nicks, cracks, uneven rims or sharp edges; do not use if the jars are damaged.
  • Wash jars and lids in hot soapy water; rinse well.
  • Place mason jars on a rack in a boiling water canner.
  • Fill canner with enough water to cover jars.
  • For all recipes, heat water to a simmer (180°F/82°C).
  • Allow jars to remain in hot water until needed.

Set screw bands aside; heat lids in hot water, not boiling (180°F/82°C); keep hot until used.

  • Fill one jar at a time.
  • Ladle or pour prepared food product into jar, leaving proper ‘headspace’ as indicated in recipe.
  • Remove air bubbles by sliding a non-metallic utensil between jar and food; readjust headspace if necessary.
  • Wipe jar rim, removing any food residue.
  • Centre hot lid on clean jar rim. Screw band down until resistance is met, then increase to fingertip tight. Return filled jar to rack in canner. Repeat for remaining jars and food.


In home canning terms, “processing” means heating filled jars at the temperature and time required to destroy spoilage microorganisms, inactivate enzymes and vent excess air from the jar. As the filled jar is heated, headspace pressure increases until air is vented from the jar. After processing, the atmospheric pressure outside the jar is greater than inside due to this "venting". This pressure difference causes the lid to be pushed down onto the jar, resulting in a true vacuum seal. This seal prevents microorganisms and air from entering and contaminating the food.

There are only two “heat processing” techniques recommended for safe home canning.

The acidity of the food you are home canning dictates the processing method. Heat processing methods are not interchangeable.


High Acid Foods include jams, jellies and other soft spreads, fruits and fruit juices, pickled fruits and vegetables, relishes, chutney, salsa, tomatoes with added acid and high acid fruit-tomato sauces and condiments. This technique requires filled, closed jars of food to be placed on a rack, immersed in water, brought to a rolling boil and boiled steadily for the “processing time”. The type of food and jar size determines this time.


Low Acid Foods include all vegetables, meat and game, poultry, fish, seafood, soups, stews, tomato-vegetable sauces and tomato-meat sauces.

Because the steam inside the canner is pressurized, its temperature exceeds the boiling point of water--212°F (100°C). Therefore, filled jars can be heated to 240°F (116°C). The food is held at this pressure and temperature for the “processing time” specified in up-to-date, tested home canning recipes. These times and temperatures have been established to destroy all bacteria, their spores and the toxins they can produce. In low acid foods, failure to destroy the bacterium, Clostridium botulinum can cause botulism, a deadly form of food poisoning. Boiling water canners are not appropriate for safe processing of low acid foods.

Botulism is a deadly disease caused by ingesting the toxic substance produced by the bacterium Clostridium botulinum (C. botulinum). This is a concern with improperly canned food.

Background on BOTULISM:

Spores of the bacterium C. botulinum are found everywhere in nature. In normal cases, the spores are of no harm to us. However, in certain environments, the spores produce vegetative cells. It is these cells that produce the deadly toxin. The following circumstances are favourable for C. botulinum spores to produce toxic vegetative cells:

  • a low acid environment (>4.6), such as vegetables and meats
  • the absence of air, such as a sealed mason jar
  • a moist environment, such as food

The environment described above is identical to a jar of canned low acid food. Low acid food includes: all vegetables (not pickles), meat, fish, seafood, game and tomatoes without added acid.

The Solution to BOTULISM:

Low acid foods may still be safely home canned. Botulism spores can be destroyed by a temperature of 116ºC (240ºF). This high temperature can only be achieved by the use of pressure in a pressure canner. Home canning recipes for some common low acid foods are available from BERNARDIN®. These provide instructions and the proper processing times for that food.

Note: Botulism is a frightening disease, not only because it may cause death, but because it is very difficult to detect in home canned food. C. botulinum has no smell and does not produce a gas. It is crucial that all low acid food be canned in a pressure canner for the appropriate time and pressure recommended.

High acid food includes jams, jellies, fruits, pickles, relishes, salsas and tomatoes with added acid. These foods have no risk of botulism, if properly prepared, due to their natural acidity.   

< Back to TOP

Can I can Lobster?

Unfortunately, lobster is not one of the foods for which home canning in mason jars is recommended. The recommended home preservation method for lobster is freezing.

We have searched the U.S. and Canada, talking to a broad range of food authorities. There is no record of any university or food processing authority development of a method and/or time for safe processing of lobster in mason jars, at this time..

First, lobster is a very delicate meat of relatively high fat content. But, more importantly, it is also a low acid food that requires processing (heating filled jars) in a pressure canner.  Unlike boiling water canners, pressure canners heat food at elevated temperatures – 240°F (116°C) - to destroy spores of clostridium botulinum. When not inactivated, these spores can grow and lead to a deadly form of food poisoning called botulism. The heat and time required to destroy the spores and safely heat process lobster in a pressure canner would undoubtedly turn the lobster meat to mush making it most unappetizing.

Now, we are aware that some people in coastal areas "put up" lobster in jars utilizing a variety of handed-down methods, most of which appear to involve a boiling water canner. Moreover, our research has led us to believe that most of the processing times being used in this “handed-down method” are woefully inadequate. Quite frankly, these people are playing a very dangerous game of chance with their family's health. Unlike many microorganisms, spores of clostridium botulinum can lurk undetected in inadequately or poorly preserved foods. These spores are not detectable to the eye, touch or nose. In fact, they are very difficult to detect in a sophisticated lab.

We realize this is not the answer you wanted, but we trust that it will convince you to freeze lobster in the future. BERNARDIN® does have tested recipes for preserving salmon, clams, crab meat, oyster, tuna and fish in mason jars in the 3rd edition of the BERNARDIN® Guide to Home Preserving.

< Back to TOP

Why does Fruit Float?

Floatation occurs frequently and naturally in canned fruits and vegetables. Although it may be visually unappealing, it is not dangerous by any means. There are, however, some steps that you can take to keep your home canned food looking as good as it taste.


  • Use fully ripe, unblemished produce. Do not use overripe produce.
  • Pack produce firmly into jars. Straight-sided jars allow produce to float. Using jars with “shoulders” helps hold food down in the jars.
  • Avoid too heavy of a syrup. Decrease the sugar concentration the next time if you feel that it has contributed to floatation.
  • Process only for the time indicated in recipe. Over-processing will cook the natural pectin in fruits unnecessarily and damage it. Pectin helps fruits hold their shape.
  • Process foods using a boiling water canner unless a pressure canner is indicated in the recipe. Pressure canning high acid foods may over-cook them and lead to more floatation.
  • Hot pack your foods. Heat your fruits or vegetables in their canning liquid before packing in jars to remove air within the tissues. If packed cold, this air will contribute to floatation and discolouration. NOTE: Do not pre-heat pickles or citrus fruit before filling jars.
  • Take care not to damage the produce before canning. This may activate enzymes that destroy the natural pectin, leading to floatation.

< Back to TOP

Freezing with BERNARDIN® Mason Jars

Mason jars go from fridge to table in style! These jars are the perfect containers for freezing no-cook jams, as well as other foods intended for refrigerated storage. Simply thaw frozen jars in the fridge and they’re ready to serve. Unlike plastic, mason jars do not absorb food colours and flavours. They are dishwasher safe and can be sterilized in boiling water if desired. Because they can be reused over and over, mason jars are an economical choice for freezer storage.

IMPORTANT: All mason jars that have straight sides and no shoulders may be used for successful freezing. When freezing, food expands upward and does not take the shape of its container. This can cause jars that are not appropriate for freezing to break.


  • BERNARDIN® Decorative Mason Jars – 125 ml, 250 ml, and 500 ml sizes
  • BERNARDIN® 250 ml Preserve ‘n Serve Mason Jar

WHEN FREEZING FOOD IN MASON JARS: Leave sufficient head space for the food to expand:
  • 1/2 inch (1 cm) for freezer jams in 125 or 250 ml size jars
  • 1/2 to 1 inch (1 to 2.5 cm) for larger jars, depending on the type of food. Foods with higher water content expand more than foods with dense texture.
  • Close jars using BERNARDIN Plastic Storage Lids, available in Standard (70 mm) and Wide mouth (86 mm). Bernardin 2-piece SNAP LID® closures may also be used.

< Back to TOP

Can I use Oil in Home Canning?

It is not recommended to use large amounts of oil in home canning recipes. Grocery stores carry commercial items such as pesto, garlic in oil and flavoured oils, but these cannot safely be canned in your home. Most home canning recipes using oil are intended for short-term refrigerator storage only.

WHY? Because of the harmful bacteria Clostridium botulinum (C. botulinum), the cause of botulism. C. botulinum produces a deadly toxin when in an environment that is:
  • low acid (pH > 4.6)
  • anaerobic, or absent of oxygen
  • room temperature
  • moist
These conditions are identical to those inside a home canned mason jar containing oil. Home canning with oils may promote the growth of C. botulinum, causing food poisoning to anyone who consumes it, possibly resulting in death. Instead, make your recipe using oil and store it in the refrigerator for up to three weeks. Use fresh, clean ingredients and utensils when making your recipe and discard any leftovers after 3 weeks.

For more information, visit www.foodsafety.ufl.edu/consumer/or/or001.htm

< Back to TOP

What Types of Foods Should I Pressure Can?

Low acid foods such as vegetables, meats, poultry and seafood can only be safely processed in a pressure canner.

< Back to TOP

What are the Pressure Canner Styles?

Weighted gauge pressure canners have small weights that regulate pressure at 5, 10 or 15 lbs of pressure. When the recommended pressure is reached, the weight begins to jiggle or rock. Each time the weight jiggles a small amount of steam is exhausted in order to maintain a constant pressure.

Dial gauge pressure canners have an exterior dial that measures the internal pressure very precisely. In order to maintain accuracy and prevent under processing, the dial gauge should be checked annually.

Sealing gaskets:  Examine the sealing gasket on either style of canner annually to check for cracks, tears, stretching or drying out. Old sealing gaskets allow steam to escape from the edge of the canner lid and prevent the proper build-up of pressure.

  • Visually inspect mason jars for nicks, cracks uneven rims or sharp edges.
  • Wash jars and lids in hot soapy water; rinse well.
  • Place mason jars on the rack in your pressure canner.
  • Fill canner with 2 to 3 inches (5 to 8 cm) of water, bring water to a simmer to thoroughly heat mason jars prior to filling.
  • Allow jars to remain in hot water until required.



  • Fill one jar at a time.
  • Pack prepared food product into jar leaving proper ‘headspace’ as indicated in recipe.
  • Remove air bubbles by sliding a non-metallic utensil between jar and food; readjust headspace if necessary.
  • Wipe jar rim removing any food residue.
  • Centre hot lid on clean jar rim. Screw band down until resistance is met, then increase to fingertip tight. Return filled jar to rack in canner ensuring jars are covered by water.

  • When all jars are filled and canner is full, lock canner lid in place, leaving vent open. Turn stove on high heat. Allow steam to escape steadily for 10 minutes.
  • Close the vent using the weight or method described for your canner. Gradually reduce the heat to achieve and maintain the recommended pressure. Regulate heat only with gradual changes to heat level.
  • Once canner reaches specified pressure for your altitude, begin counting ‘heat processing’ time.

Pressure cookers are generally smaller in size and capacity than pressure canners. Since pressure canning heat processing time is calculated to included both the heat up and cool down times of a pressure canner, it is essential to always use a proper “pressure canner” specially designated for processing low acid foods.

< Back to TOP

What are the Pressure Canner Companies and Who Can I Contact for Maintenance?

National Presto Industries, Inc.
(for shipping

3925 North Hastings Way
Eau Claire, WI 54703-3703  

National Presto Industries, Inc.
(for letters)

P.O. Box 1172
Eau Claire, WI 54702

Customer Service (Parts and Questions) 1.800.877.0441 (Central Time)

Home Economist Test Kitchen (for recipes, etc): 1.800.368.2194

Or: 715.839.2201

General Office: 715.839.2121
(8:30am-4pm Central Time)

Fax: 715.839.2122


Notes: Presently Presto makes only dial gauge canners, although they made good quality weighted gauge canners in the past. There is a Home Economist on staff. They offer canners, booklets, manuals, repairs and replacement parts. For consumer questions, write to “Home Economics Dept, National Presto Industries, etc”. Canners have either “Presto” or “National” (older) brand name. Consumer questions should go to P.O. Box address –it’s faster.


P.O. Box 1330
Manitowoc, WI  54221-1330

Notes: Make weighted gauge only

Direct Consumer Line: 1.800.527.7727

Parts: 1.800.236.2433

Switch Board: 1.800.558.7797
Consumer service ext. 6524

(Central Time) Same as direct consumer line.

Wisconsin Aluminium Foundry Co., Inc. (All-American Pressure Canner)

P.O. Box 246
(838 South 16th Street)
Manitowoc, WI 54221-0246

Notes: Canners have metal to metal closure (no gasket) and clamps around the lid that screw onto the bottom.

Consumer Products Division: 920.682.8627
(Central Time)

Fax: 920.682.4090


Replacement Parts and New Canners:

Try Home Hardware (for Presto) or Canadian Tire (for Mirro)

Pressure Canner Gauge Testing/Repair:

  • Any Hydraulic Equipment Repair Shop
  • Welding Equipment Shop
  • Plumbers who deal with boilers can check and repair

< Back to TOP