Written by Abigail Lambert under the direction and review of Hope Kleine.
Steam canning is a quick and simple method of preserving produce using steam. While steam canning was previously not an evidence-based practice, recently the University of Wisconsin published research indicating steam canning may be a safe home food preservation canning method for naturally acid and acidified foods.
Steam canners may look similar to water bath canners or they may have a shallow bottom, a wire rack that holds jars above the base and a dome-shaped lid (see below). Jars sit on a rack above the water-filled base. Processing is done by hot steam. The steam canner uses less water than a water bath canner. This helps speed up the processing time as there is less water to heat. It also makes it easier to remove from the heat after processing is complete.
A few Things to Consider when using a Steam Canner.
- Foods must have a pH of 4.6 or lower in order to process safely.
- A research-tested and evidenced-based recipe must be used. Recipes made for a water bath canner can be adapted for a steam canner. Find recipes for acid and acidified foods in our Preserve it! resources. The booklet accompanying the steam canner cannot be relied on to provide safe canning instructions.
- Jars must be heated before filling and can be hot or raw packed.
- Regulate heat, as a canner that is boiling too vigorously can boil dry within 20 minutes. If the canner boils dry, the food is considered under-processed and can be unsafe.
- Only ¼-pint, ½-pint, pint, or quart jars can be used.
- Remember to modify the processing time depending on your altitude.
To Use a Steam Canner:
Hot or raw pack produce into hot jars and fill with hot liquid. Place the rack in the bottom of the canner and fill with water until just over the rack.
Preheat water. Once preheated, place jars in canner and secure the lid.
Process in pure steam at 210-212 degrees F for the recommended time. Steam must flow through the canner vent during the process or the food is considered unsafe to consume. Begin timer once a steady stream of steam is visible from vent. Monitor and regulate the temperature throughout the processing time.
Processing must take 45 minutes or less. If processing takes longer than 45 minutes, the canner may boil dry and not maintain the correct temperature range. The canner must not be opened at any point during processing.
Once processing is complete, remove canner from heat and let stand for 5 minutes before removing the lid. Remove jars from canner and let cool.
To learn more about canning equipment, watch our Canning Equipment video!
- P. Willmore, M. Etzel, E. Andress, and B. Ingham. 2015. Home Processing of Acid Foods in Atmospheric Steam and Boiling Water Canners. Food Protection Trends. 35:150-160.
- Inghram, B. Guidelines for Using an Atmospheric Steam Canner for Home Food Preservation. University of Wisconsin Extension. 2011.