Home canning or bottling, also known colloquially as putting up or processing, is the process of preserving foods, in particular, fruits, vegetables, and meats, by packing them into glass jars and then heating the jars to create a vacuum seal and kill the organisms that would create spoilage.
Though ceramic and glass containers had been used for storage for thousands of years, the technique of canning which involves applying heat for preservation was only invented in the first decade of the 1800s. Before that, food storage containers were used for non-perishable foods, or with preservatives such as salt, sugar, vinegar, or alcohol.
Water bath canning is appropriate for high-acid foods only, such as jam, jelly, most fruit, pickles, and tomato products with acid added. It is not appropriate for meats and low-acid foods such as vegetables. This method uses a pot large enough to hold and submerge the glass canning jars. Food is placed in glass canning jars and placed in the pot. Hot water is added to cover the jars. Water is brought to a boil (212 °F (100 °C)) and held there for at least 10 minutes. Different foods require a different length of time under boil; larger jars require longer times.[1]
Pressure canning
Pressure canning is the only safe home canning method for meats and low-acid foods. This method uses a pressure canner — similar to, but heavier than, a pressure cooker. A small amount of water is placed in the pressure canner and it is turned to steam, which without pressure would be 212 °F (100 °C), but under pressure is raised to 240 °F (116 °C). Based on the recipe, the canner is heated until the correct pressure is reached, and the jars left for the appropriate amount of time (charts have been published with times and pressures). The heat is turned off, pressure reduced, canner opened, and hot jars carefully lifted out and placed on an insulated surface (towels, wood cutting board, etc.) and out of drafts to cool.[2]
Safety
While it is possible to safely preserve many kinds of foodstuffs, home canning can expose consumers to botulism and other kinds of food poisoning if done incorrectly.[3][4] The most common source of food-borne botulism is home-canned foods prepared in an unsafe manner.[5] Safety measures must be taken when performing home canning, since ingestion of toxin in food produced by Clostridium botulinum can cause death.[6] Because of the high risk of illness or death associated with improper canning techniques, the United States Department of Agriculture (USDA) considers it critical that consumers who intend to can at home obtain proper and current information from a reliable source.[7] At the basis of these recommendations is the balance between bringing the food to a high enough temperature for a long enough time that spoilage and disease-producing microorganisms are killed, while not heating the food so much that it loses nutritive value or palatability.
Unsafe methods
A 1914 advertisement for a combination steam canner and roaster. The described method will not protect against botulism.
The following methods have been determined to be unsafe food preservation techniques:[8][9]
Open-kettle — Heating food in an open kettle, then pouring into jars, closing with a lid, and not further processing.
Canning powders — alleged preservatives. They do not replace the need for proper heat processing.
Atmospheric steam canning — Processing with 100 °C steam, not under pressure[12]
Use of vintage style sealing materials such as jars with wire bails and glass caps, or zinc caps with rubber rings.
Water bath canning method for low-acid foods (foods with pH greater than 4.6).[13]
Otherwise correct water bath or pressure canning but processing for too little time, the wrong pressure, or not considering variations in time/pressure due to altitude.
Re-using one-use seals
Using cracked or chipped jars
North America
Green beans in a pressure canner ready to be processed
In North America, home canning is usually done in Mason jars, which have thicker walls than single-use commercial glass jars. Unless the food being preserved has a high acid content (pH <4.6) or salt or sugar content resulting in water availability <0.85, such as pickles or jellies, the filled jars are also processed under pressure in a canner, a specialized type of pressure cooker. Ordinary pressure cookers are not recommended for canning as their smaller size and the reduced thickness of the cooker wall will not allow for the correct building up and reducing time of pressure, which is factored into the overall processing time and therefore will not destroy all the harmful microorganisms.[14] The goal in using a pressure canner is to achieve a "botulinum cook" of 121 °C for 3 minutes, throughout the entire volume of canned product. Canners often incorporate racks to hold Mason jars, and pressure canners are capable of achieving the elevated temperatures needed to prevent spoilage.
The most common configuration is a Mason jar with a flat lid and screw ring. The lid is generally made of plated or painted steel, with an elastomeric washer or gasket bonded to the underside of the rim. The lid also incorporates a slightly dimpled shape, which acts as an indicator of the vacuum (or lack thereof) inside a sealed jar. A newer reusable lid is now available that uses a flat plastic disk with a reusable rubber gasket. The ring threads onto the top of the jar over the lid to hold it in place while the jar cools after processing; the ring can be removed once a vacuum has been established in the jar. Jars are commonly in either pint or quart capacities, with two opening diameters, known as "standard" and "wide mouth".
When a jar has cooled and is properly sealed, pressing the dimple on the lid will not make any sound. An improperly sealed jar will allow the dimple to move up and down, sometimes making a popping noise. Lack of this noise does not necessarily indicate that the food in the jar is properly preserved. Typically, during the cooling process, a properly sealed lid will pop once as the pressure inside the jar is reduced enough that atmospheric pressure pushes the lid inward.
Older variations had a ceramic seal inside a one-piece zinc lid. Another method that is no longer recommended was the use of layer of hot paraffin wax poured directly over the top of the food (especially jams and jellies) to seal it from air, thus reducing growth of aerobic microorganisms like mold.
United Kingdom
In the United Kingdom home bottling is done with Kilner jars in a similar way to the Mason jars in the US, and although old-style Kilner jars have a glass lid without a "dimple" more recent varieties do.[15][16][17]
Australia
In Australia the most popular home canning system is Fowler's Vacola. This system uses glass jars, single use seals, metal lids, and a water bath canning sterilization process. During the canning process the lids are secured by metal tension clips which are removed once a vacuum seal has formed.[18] Fowler's Vacola products are still produced and are available from some hardware stores. Used equipment is frequently sold on online auction sites and in opportunity shops.
Germany
Weck glass with rubber seal and steel tension clips. The red tongue pointing downwards indicates a correct seal
In Germany the most popular home canning system is Weck jar. This system uses glass jars, rubber seals, glass lids, and a water bath canning sterilization process.[19]
^"Pressure Canning: Beginner's Guide and Recipes". Almanac.com. Retrieved 2023-01-02.
^Mendelson, C. (2005). Home Comforts: The Art and Science of Keeping House. Scribner. p. 180. ISBN978-0-7432-7286-5. Retrieved November 2, 2017.
^The Complete Book of Home Canning. Skyhorse Publishing. 2015. p. 25. ISBN978-1-63220-886-6. Retrieved November 2, 2017.
^Centers for Disease Control and Prevention: Botulism in the United States, 1899-1996. Handbook for Epidemiologists, Clinicians, and Laboratory Workers, Atlanta, GA. Centers for Disease Control and Prevention, 1998.
, documents the history of glass manufacturing, with an emphasis on fruit and vegetable canning jars at the Ball State University Archives and Special Collections Research Center
March 06, 2023
home, canning, commercial, process, canning, bottling, also, known, colloquially, putting, processing, process, preserving, foods, particular, fruits, vegetables, meats, packing, them, into, glass, jars, then, heating, jars, create, vacuum, seal, kill, organis. For the commercial process see canning Home canning or bottling also known colloquially as putting up or processing is the process of preserving foods in particular fruits vegetables and meats by packing them into glass jars and then heating the jars to create a vacuum seal and kill the organisms that would create spoilage Preserved food in Mason jars Though ceramic and glass containers had been used for storage for thousands of years the technique of canning which involves applying heat for preservation was only invented in the first decade of the 1800s Before that food storage containers were used for non perishable foods or with preservatives such as salt sugar vinegar or alcohol Contents 1 Techniques 1 1 Water bath canning 1 2 Pressure canning 2 Safety 2 1 Unsafe methods 3 North America 4 United Kingdom 5 Australia 6 Germany 7 Standard jar sizes 8 See also 9 References 10 External linksTechniques EditWater bath canning Edit Water bath canning is appropriate for high acid foods only such as jam jelly most fruit pickles and tomato products with acid added It is not appropriate for meats and low acid foods such as vegetables This method uses a pot large enough to hold and submerge the glass canning jars Food is placed in glass canning jars and placed in the pot Hot water is added to cover the jars Water is brought to a boil 212 F 100 C and held there for at least 10 minutes Different foods require a different length of time under boil larger jars require longer times 1 Pressure canning Edit Pressure canning is the only safe home canning method for meats and low acid foods This method uses a pressure canner similar to but heavier than a pressure cooker A small amount of water is placed in the pressure canner and it is turned to steam which without pressure would be 212 F 100 C but under pressure is raised to 240 F 116 C Based on the recipe the canner is heated until the correct pressure is reached and the jars left for the appropriate amount of time charts have been published with times and pressures The heat is turned off pressure reduced canner opened and hot jars carefully lifted out and placed on an insulated surface towels wood cutting board etc and out of drafts to cool 2 Safety EditWhile it is possible to safely preserve many kinds of foodstuffs home canning can expose consumers to botulism and other kinds of food poisoning if done incorrectly 3 4 The most common source of food borne botulism is home canned foods prepared in an unsafe manner 5 Safety measures must be taken when performing home canning since ingestion of toxin in food produced by Clostridium botulinum can cause death 6 Because of the high risk of illness or death associated with improper canning techniques the United States Department of Agriculture USDA considers it critical that consumers who intend to can at home obtain proper and current information from a reliable source 7 At the basis of these recommendations is the balance between bringing the food to a high enough temperature for a long enough time that spoilage and disease producing microorganisms are killed while not heating the food so much that it loses nutritive value or palatability Unsafe methods Edit A 1914 advertisement for a combination steam canner and roaster The described method will not protect against botulism The following methods have been determined to be unsafe food preservation techniques 8 9 Open kettle Heating food in an open kettle then pouring into jars closing with a lid and not further processing Oven canning 10 Dry canning Processing dry goods or vegetables without the addition of liquids in an oven 10 11 Canning food in a microwave oven slow cooker or pressure cooker Canning powders alleged preservatives They do not replace the need for proper heat processing Atmospheric steam canning Processing with 100 C steam not under pressure 12 Use of vintage style sealing materials such as jars with wire bails and glass caps or zinc caps with rubber rings Water bath canning method for low acid foods foods with pH greater than 4 6 13 Otherwise correct water bath or pressure canning but processing for too little time the wrong pressure or not considering variations in time pressure due to altitude Re using one use seals Using cracked or chipped jarsNorth America Edit Green beans in a pressure canner ready to be processed In North America home canning is usually done in Mason jars which have thicker walls than single use commercial glass jars Unless the food being preserved has a high acid content pH lt 4 6 or salt or sugar content resulting in water availability lt 0 85 such as pickles or jellies the filled jars are also processed under pressure in a canner a specialized type of pressure cooker Ordinary pressure cookers are not recommended for canning as their smaller size and the reduced thickness of the cooker wall will not allow for the correct building up and reducing time of pressure which is factored into the overall processing time and therefore will not destroy all the harmful microorganisms 14 The goal in using a pressure canner is to achieve a botulinum cook of 121 C for 3 minutes throughout the entire volume of canned product Canners often incorporate racks to hold Mason jars and pressure canners are capable of achieving the elevated temperatures needed to prevent spoilage The most common configuration is a Mason jar with a flat lid and screw ring The lid is generally made of plated or painted steel with an elastomeric washer or gasket bonded to the underside of the rim The lid also incorporates a slightly dimpled shape which acts as an indicator of the vacuum or lack thereof inside a sealed jar A newer reusable lid is now available that uses a flat plastic disk with a reusable rubber gasket The ring threads onto the top of the jar over the lid to hold it in place while the jar cools after processing the ring can be removed once a vacuum has been established in the jar Jars are commonly in either pint or quart capacities with two opening diameters known as standard and wide mouth When a jar has cooled and is properly sealed pressing the dimple on the lid will not make any sound An improperly sealed jar will allow the dimple to move up and down sometimes making a popping noise Lack of this noise does not necessarily indicate that the food in the jar is properly preserved Typically during the cooling process a properly sealed lid will pop once as the pressure inside the jar is reduced enough that atmospheric pressure pushes the lid inward Older variations had a ceramic seal inside a one piece zinc lid Another method that is no longer recommended was the use of layer of hot paraffin wax poured directly over the top of the food especially jams and jellies to seal it from air thus reducing growth of aerobic microorganisms like mold United Kingdom EditIn the United Kingdom home bottling is done with Kilner jars in a similar way to the Mason jars in the US and although old style Kilner jars have a glass lid without a dimple more recent varieties do 15 16 17 Australia EditIn Australia the most popular home canning system is Fowler s Vacola This system uses glass jars single use seals metal lids and a water bath canning sterilization process During the canning process the lids are secured by metal tension clips which are removed once a vacuum seal has formed 18 Fowler s Vacola products are still produced and are available from some hardware stores Used equipment is frequently sold on online auction sites and in opportunity shops Germany Edit Weck glass with rubber seal and steel tension clips The red tongue pointing downwards indicates a correct seal In Germany the most popular home canning system is Weck jar This system uses glass jars rubber seals glass lids and a water bath canning sterilization process 19 Standard jar sizes EditUnited States 4 ounce jelly 8 ounce jelly 8 ounce half US pint 236 ml 16 ounce US pint 473 ml 24 ounce US pint and a half 710 ml 32 ounce US quart 946 ml 64 ounce half US gallon 1892 ml Metric 250 ml 500 ml half litre 750 ml three quarters of a litre 1000 ml litre 1900 ml half US gallon See also Edit Food portalNicolas Appert Weck jar Canning Food preservation Pickling Pressure cookingReferences Edit Water Bath Canning Beginner s Guide Almanac com Retrieved 2023 01 02 Pressure Canning Beginner s Guide and Recipes Almanac com Retrieved 2023 01 02 Mendelson C 2005 Home Comforts The Art and Science of Keeping House Scribner p 180 ISBN 978 0 7432 7286 5 Retrieved November 2 2017 The Complete Book of Home Canning Skyhorse Publishing 2015 p 25 ISBN 978 1 63220 886 6 Retrieved November 2 2017 Centers for Disease Control and Prevention Botulism in the United States 1899 1996 Handbook for Epidemiologists Clinicians and Laboratory Workers Atlanta GA Centers for Disease Control and Prevention 1998 National Botulism Surveillance Botulism CDC www cdc gov 2021 10 06 Retrieved 2023 01 02 Critical Review of Home Preservation Literature and Current Research nchfp uga edu Retrieved 2023 01 02 Preserving Foods Home amp Garden Information Center Clemson University South Carolina January 28 2020 Retrieved 2023 01 02 National Center for Home Food Preservation How Do I Can nchfp uga edu Retrieved 2023 01 02 a b Oven Canning Healthy Canning Retrieved 2023 01 02 Dry Canning Raw Vegetables is an Unsafe Practice Preserving Food at Home 2020 06 25 Retrieved 2023 01 02 National Center for Home Food Preservation NCHFP Publications nchfp uga edu Retrieved 2023 01 02 National Center for Home Food Preservation How Do I Can nchfp uga edu Retrieved 2023 01 02 National Center for Home Food Preservation NCHFP Publications nchfp uga edu Retrieved 2023 01 02 Kilner Jars and Parts Bottling or Home Canning Preparation Fruit and Vegetables Allotment Garden Recipes Retrieved 2023 01 02 Harvest Home Archived from the original on 2008 10 02 Retrieved 2009 03 27 Fowler s Method of Bottling Fruits and Vegetables J Fowler 26th Edition Canning Notes Weck Jars Retrieved 2023 01 02 External links EditUSDA Complete Guide to Home Canning How Do I Can from the National Center for Home Food Preservation Preservation Canning Freezing amp Drying from the South Carolina Cooperative Extension at Clemson University Richard Roller Papers documents the history of glass manufacturing with an emphasis on fruit and vegetable canning jars at the Ball State University Archives and Special Collections Research Center Retrieved from https en wikipedia org w index php title Home canning amp oldid 1141656019, wikipedia, wiki, book, books, library,
