Steam Canner Controversy
Steam canners have been used for more than 80 years, however, controversy still surrounds their use primarily because the USDA states that their use is not recommended because processing times have not been adequately researched. However, several research studies appear to contradict this USDA position:
Von Mendenhall, Ph.D. Professor Emeritus, Utah State University wrote in March 1986 to say, "Research conducted at U.S.U. and the University of Massachusetts concluded that steam canning is safe for use with high acid foods only." Dr. Mendenhall noted the following procedure to ensure the safe processing of high-acid foods:
1) Place appropriate amount of water in the base of the steam canner. Place the perforated cover over the base and bring water to a low boil
2) Pack and fill jars. Secure lids firmly, but not over-tight. Set each full jar on the canner base and allow it to warm up while packing and filling enough jars for one batch.
3) When the last full jar has warmed up for 1-2 minutes, place the dome on the base and slowly (4-5 minutes) increase temperature setting of the stove until a column of steam 8-10 inches is evident from the small holes at the base of the dome.
4) Begin timing the process, maintaining the column of steam following the water bath canning recommendations adjusted for your altitude. Do not reduce temperature setting of the stove. The dome should not bounce from the base during processing.
5) When processing time is complete, turn off the stove and wait 2-3 minutes before removing the dome. Remove the dome by turning it away from your face and body to avoid burns.
6) Allow jars to cool and seal. Remove metal bands and store the jars in a cool dark place.
Additional Steam Canner Research
Dr. George York from the University of California published research in March of 2005 in which four foods of different densities were processed. The conclusion reached by the research was that the processing times for steam canners are essentially the same as for water bath canners and that both types are equally safe to use for high acid foods.
Final Thoughts on Steam Canner Use
Steam canners are NOT the same as pressure canners. Steam canners should be used like water bath canners and are for high acid foods only. Any low acid (e.g. meats, vegetables) or borderline acid foods (e.g. tomatoes without added acid) require the use of a pressure canner to prevent botulism food poisoning.
Canning experts, Paul & Bernice Noll have this to say about their steam canner: "Our steam canner accomplishes all we need in a water bath canner. It has a number of good advantages. We would never go back to water bath for these reasons:
So given proper handling, steam canners appear to be as safe for high-acid foods as water-bath canners. Give a steam canner a try; you might love its fast heating times.
- Uses less water. Important for us with a well.
- Takes far less heat to get going due to less water to get boiling. Important in a hot summer.
- Those big water bath canners can be difficult to lift full of water.
You can't put jars that are not hot in a water bath of boiling water. Jars will break. In a steam canner you can set the jars, cold or hot on the rack with the water below boiling with no problem. So cycling batches is much easier and faster.