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To Can Peas
Fill glass jars full of uncooked peas, then pour in sufficient cold water to fill to the very top, and lay the tops on the jars. Place straw or hay in the bottom of a wash boiler; place the jars on this, or better still, stand in a wire frame.
Pour around sufficient cold water to half cover the jars. Put the boiler over a moderate fire, cover closely with the lid and boil steadily three hours. Lift out the jars, see that each is filled with boiling water to overflowing, screw on the covers as tightly as possible, stand aside, where the air will not strike them, to cool. When cold, again screw the covers, wipe the jars, and place them in a dark, cool, dry place. If the peas shrink in cooking, it is well to empty one jar to fill the others.
This is a boiling-water method for a low-acid vegetable, and it is the single canning procedure that modern food-safety authorities single out as unsafe at any duration. The points below explain why the failure is specific to peas rather than general caution.
- The pathogenClostridium botulinum spores survive boiling. In a sealed jar of peas — low acid, moist, oxygen-free — they germinate and produce botulinum toxin, which can be present with no smell, no bubbling and no bulging lid. Home-canned low-acid vegetables are among the most commonly documented vehicles for botulism in North America.
- Why three hours does not fix itWater in a boiler that is not pressurised cannot exceed about 212F at sea level, and less at altitude, while the spores need roughly 240F to be destroyed. Extending the time does not raise the temperature; it only overcooks the peas. The three-hour time probably reflects a period assumption that long boiling meant sterility.
- The lid stepLaying the tops on loosely and tightening after processing also appears in other period instructions for screw-band jars, but tightening a hot jar and then re-tightening when cold gives a seal of unknown reliability. A vacuum seal proves nothing about whether spores were killed.
- "Where the air will not strike them"This instruction most likely addresses thermal shock cracking the glass rather than contamination.
- Topping up from another jarEmptying one jar to fill the others introduces handling and cooling at exactly the point where the contents are most vulnerable. It is a sound instinct about headspace applied to an unsound process.
- If you want canned peasUse a current tested recipe for a pressure canner from a food-safety extension service, which will specify pounds of pressure and minutes by jar size and altitude. Peas can also simply be blanched and frozen.
- Jars already made this wayHome-canned low-acid vegetables of unknown provenance should be discarded without tasting, and without opening where possible. Tasting to check is not a test.
Home canning of vegetables spread rapidly through American households in the last quarter of the nineteenth century, after the Mason-type screw-top jar made a reusable, resealable glass container cheap and widely available. The method described here is a familiar one: fill, submerge in a wash boiler padded with straw or hay to keep the glass off the hot metal, boil a long time, seal. That worked well enough for fruit, tomatoes and pickles, whose acidity suppresses Clostridium botulinum, and it is why those recipes survived while vegetable recipes like this one did not. Botulinum was identified in the 1890s, but the connection between low-acid home canning and the toxin was not widely understood by domestic cooks until the 1910s and 1920s, when a series of outbreaks and the subsequent extension-service campaigns established pressure canning as the only acceptable method. This recipe comes from the era when the instructions were confident and the science had not yet caught up.