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Canned Beans
Prepare string beans as for boiling. Cook in water one half hour. Fill sterilized jars with beans, adjust rubbers, fill with cold water, and put on covers. Arrange on rack in boiler, fill boiler two thirds full with water, cover boiler, and boil hard two hours. Seal and remove jars.
This is a boiling-water-bath method for a low-acid vegetable, and it is the single most dangerous class of instruction in early twentieth-century preserving chapters. The reasons are specific.
- Green beans are low-acidString beans sit around pH 5.5, well above the 4.6 threshold below which Clostridium botulinum cannot grow. Nothing in this recipe acidifies them — no vinegar, no lemon, no brine of consequence.
- Boiling water cannot reach the necessary temperatureA covered boiler of water tops out at 212F at sea level. Botulinum spores are highly heat-resistant and are not reliably destroyed at that temperature by any practical boiling time; destroying them in a sealed low-acid jar requires 240-250F, which is only attainable under pressure. Two hours of hard boiling produces a sterile-tasting jar that is not sterile.
- The sealed jar is the hazard, not the beansAn anaerobic, moist, low-acid, room-temperature jar is close to an ideal culture vessel. Surviving spores germinate and produce toxin over weeks, often with no bulging lid, no off smell and no cloudiness to warn you.
- Sealing after processing"Seal and remove jars" reflects the old glass-top-and-rubber-ring closures, tightened once the jars came out. Modern two-piece lids seal during cooling, so the sequence here does not map onto current equipment even mechanically.
- Pre-cooking does not helpThe half hour of open-kettle boiling before filling kills spoilage organisms and vegetative bacteria but leaves spores untouched. It softens the beans and gives a false impression of thoroughness.
- If you want canned beansUse a current tested pressure-canning procedure from a food-safety authority, or freeze them instead. Do not adapt the timing above.
Lowney's, like many American household books of its generation, treated the wash boiler as a universal preserving vessel: jars on a rack, water two-thirds up, lid on, boil hard. Home pressure canners were available commercially in the early decades of the century but were expensive and uncommon in domestic kitchens, so cookbook authors extended the water-bath method — genuinely adequate for fruit, tomatoes and pickles — to beans, corn, peas and meat, sometimes recommending repeated boiling on successive days in the hope that successive heatings would finish what one could not. C. botulinum was identified in the nineteenth century, but the link between home-canned vegetables and outbreaks was pinned down largely through American public-health work in the late 1910s and 1920s, after which extension services began the long campaign that eventually made "pressure-can all low-acid foods" standard advice. Pages like this one are a snapshot of confident practice from just before that knowledge arrived.