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Green String Beans and Wax Beans
-The beans should be tender and fresh, and graded according to size and washed. Leave whole or break in uniform pieces. Blanch 5 to 10 minutes or until the pod will bend without breaking. Cold dip, drain well and pack into hot jars. Add salt and cover with boiling water. Loosely seal and sterilize two hours in boiling water. Remove as soon as time is up, tighten covers, invert to test seal and cool. Label and store.
This is a boiling-water-bath method for a low-acid vegetable, and that is precisely the combination modern food safety rules out. The terms are worth translating, but the process itself has been superseded and should not be followed.
- Why it fails: botulismGreen and wax beans are low-acid, with a pH well above 4.6, which is the range in which Clostridium botulinum spores germinate and produce toxin in the anaerobic interior of a sealed jar. Water at sea level tops out at 212F no matter how long it boils, and that temperature does not destroy the spores. Two hours of boiling water gives a jar that looks sealed and can still be lethal.
- What the temperature has to beDestroying botulinum spores in a low-acid food requires roughly 240-250F, which can only be reached under steam pressure. Any current instructions for canning beans call for a pressure canner and specify pounds of pressure and minutes for the jar size and altitude. Use a present-day tested procedure from a food-safety authority rather than this one.
- "Loosely seal" and invertingThe wording points to period closures, most likely zinc-ring or glass-top jars, processed with the closure slack so air can escape and tightened afterward. Inverting a hot jar to check for leaks is an obsolete test; it tells you nothing about whether the contents were heated enough, and with modern two-piece lids it can interfere with sealing.
- "Cold dip"An older term for plunging the blanched beans into cold water to halt cooking. The instruction itself is sound kitchen practice; it is the processing that follows that is the problem.
- Unmeasured salt, unspecified headspace"Add salt" gives no quantity, and there is no mention of leaving headspace at the top of the jar. Modern schedules fix headspace exactly (salt is optional, added for flavour), and the absence of either figure is a fair sign of how much this method leaves to the packer's judgment.
- If you want beans on the shelfPickled beans, acidified with vinegar to a measured strength, are a water-bath-safe preparation because the acid does the work the heat cannot. Freezing blanched beans is simpler still. Either way, work from a current recipe.
Books of this kind appeared in quantity around the First World War, when war gardens and food-conservation campaigns pushed millions of households into putting up their own vegetables, often for the first time. The boiling-water bath, sometimes with the "intermittent" or three-day variant, was the standard domestic method taught in that period, since pressure canners were expensive and not yet common in home kitchens. Botulism from home-canned vegetables was documented in the 1910s and 1920s, and over the following decades American extension services shifted toward requiring pressure processing for low-acid foods, though boiling-water instructions for vegetables persisted in print alongside the newer advice. Instructions like these survive in old cookbooks as a record of what was once ordinary advice, not as a usable schedule.