Canners and canning methods that are NOT recommended for home use
People occasionally ask, "why use a water bath method or a pressure canner, I have a steam canner that my grandmother used and she never got ill!" That may be true, just as there are occasionally smokers who live to 100 or children who play in the street and don't get hit by a car. But no rational person would recommend these either... (note: don't take MY word for it - click here to see this list of references from major universities and US government, all saying the same.)
- Open Kettle Canning The open-kettle method means placing hot food in jars and sealing with no further heat treatment. This is the method that many grandma's used (often also called "inversion") in which granny fills a jar (sterilized or not) with hot fruit, pickles, etc., puts the lid and ring on, then turns it upside down. The jar will cool and seal, BUT it is NOT sterile, as the contents were exposed to the air (and airborne bacteria) just before sealing. from that point forward, then contents cooled, so airborne bacteria were not exposed to a heat high enough, nor long enough to destroy them. Then granny gives the jars away, playing Russian Roulette. Maybe you'll get sick, maybe not. Obviously, this method is NOT recommended for home canning because the amount of heat applied may not be sufficient to destroy bacteria and the product may spoil quickly or cause illness when consumed.
- Steam Canners The steam canner was designed as a means to process foods using
steam without the aid of pressure. The manufacturer claims this process uses
less water, saves time and energy, and recommends identical processing times as
those required for boiling-water bath treatments.
Studies have concluded that:
Atmospheric steam canners result in significantly lower product temperatures at the beginning and end of the scheduled process when compared to water-bath canning.
Use of steam canners as instructed by the manufacturer would result in under processing and considerable economic spoilage. - Micro-Dome Food Preserver - Micro-Dome Food Preserver Recalled Washington, DC--The U.S. Consumer Product Safety Commission (CPSC) in cooperation with Micro-Dome of San Ramon, CA, has warned consumers of certain safety hazards associated with the use of the "Micro-Dome Food Preserver" manufactured by Micro-Dome and sold and distributed to consumers after August 1987. The CPSC has also urged consumers to destroy all food that has been preserved using a Micro-Dome Food Preserver
- Solar Canning The heat generated from captured sunlight is not a reliable method to process acid foods and should never be used to can low-acid foods.
- Oven Canning Oven-canning is extremely
hazardous. The oven canning method involves placing jars in an oven and heating.
In oven canning, product temperatures never exceed the boiling point because the
jars are not covered. It is, therefore, not safe to use for low-acid products
(e.g. meats, most vegetables) which require temperatures higher than 212 F.
Because this process fails to destroy the spores of Clostridium botulinum, it can cause the food to become toxic during storage. Also, canning jars are not designed for intense dry heat and may explode resulting in serious cuts or burns. - Microwave Processing Microwave oven cannot be used for home canning. Microwaved food reaches 212 F but heating is not uniform. There is also a danger of explosion of the jars within the microwave oven or as food is being removed from the oven.
- Dishwashing Processing Processing canned foods in a dishwater cycle is dangerous. The temperature of the water during the cleaning and rinsing cycle is far below that required to kill harmful microorganisms. Thus the product will be underprocessed and unsafe to eat. Note that it is fine to use the dishwasher to clean and sterilize the empty jars, especially if your dishwasher has a "sterilize" setting - the empty jars will get hot enough.
- Aspirin / Salicylic acid - You may have heard of someone's
grandmother canning corn by boiling the corn, adding aspirin or salicylic
acid from the drugstore, then sealing the corn in jars with no further
processing. According to the
University of Illinois, a recipe circulated several years ago, using
aspirin to acidify tomatoes and beans for canning. Aspirin is not
recommended for canning. While it contains salicylic acid, it does not
sufficiently acidify low acid foods like tomatoes or beans for safe hot
water bath canning. Low acid foods (without added acids) should only be
processed safely in a pressure canner. Lemon juice or vinegar is recommended
to acidify tomato products for safe water bath processing. You can also see
an
article in JAMA (the Journal of the American Medical Association, Vol. 289
No. 13, April 2, 2003, titled "Is salicylic acid as a food preservative
harmful?"; from which the abstract states: "salicylic acid, in
the ways in which it is used in the preparation of food products,
is not only not harmful, but is a preservative to health, inasmuch
as the process of decomposition which it prevents would be far
more dangerous."
See this page for water bath canners and see below for prices, descriptions and ordering options for pressure canners. For water bath canners and other supplies, see this page! If you have a glass top radiant stove, see Canners for glass top stovers?
References for Unsafe Canning Methods
This is just a small sampling of the many authorities who concur that the only safe home canning methods are the water bath canner (for jams and acidic fruits and vegetables) and the pressure canner (for low acid fruits and vegetables, meats, and dairy). Click on the links to see their articles.
- University of Illinois
- Montana State University
- NC State University
- North Dakota State University
- Penn State University and this page, too.
- University of Tennessee
- Utah State University
- University of Wisconsin
- United States government: USDA, FDA FoodSafety website
For other supplies:
- Books on canning, freezing, drying, preserving and jam making
- Strainers, pit removers, seed-skin-stem removers, jelly strainers, etc. All types, makes and prices (from $19 to $350)
- Vacuum Foodsealers for freezing, dried foods, and refrigerated foods - the FoodSaver line
- Canning Lids, Rings, Jars, mixes, pectin, etc.
- And just for fun, the history of the canning jar
You can also find free information from the USDA in this PDF file (it will take a while to load!) about selecting and using canners here!
For more information, and NO obligation to buy, just click on the links in the Amazon boxes on the left!
Pressure canners!If you want to can low-acid foods such as red meats, sea food, poultry, milk, and all fresh vegetables with the exception of most tomatoes, you will need a pressure canner. These foods fit into the low acid group since they have an acidity, or pH level, of 4.6 or greater. The temperature which must be reached and maintained (for a specified amount of time) to kill the bacteria is 240 F. Pressure canning is the only canning method recommended safe by the U.S.D.A. for low-acid foods such as vegetables, meats, and fish. Ordinary water bath canners can only reach 212 F and can not to kill the types of bacteria that will grow in low acid foods. This temperature can be reached only by creating steam under pressure as achieved in quality pressure canners. There are several manufacturers of pressure canners. The two leading ones are Presto and All American (Wisconsin Aluminum). They are more expensive than water bath canners, but extremely well built - I bought mine in 1988 and it still looks and works like new! |
|||
 |
Presto 01781 23-Quart Pressure Cooker/CannerAmazon usually has this (through the links at left) for about $79. (which is a GREAT price for a pressure canner). Click on the links at left for more info and current pricing. Features:
|
||
|
|
||
 |
All American Pressure Canner and Cooker #921Features:
|
||
 |
|
||
