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Lima Beans (Select perfectly sound lima)
Select perfectly sound lima beans, put into the jars uncooked, then fill the jars full of cold water. Lay on the tops and finish precisely the same as asparagus, cooking the same length of time.
This is a home-canning instruction for raw-packed lima beans, and it belongs to an era before the botulism risk in low-acid vegetables was understood. It cannot be followed safely.
- Why this one failsLima beans are a low-acid food, with a pH well above 4.6. That is the range in which Clostridium botulinum spores survive and, in the oxygen-free interior of a sealed jar, germinate and produce toxin. Nothing in this method acidifies the beans or otherwise blocks that.
- The temperature the method cannot reachDestroying botulinum spores in a sealed jar requires holding the contents at 240-250F, which is only achievable under pressure. The asparagus entry this recipe defers to is not given here, but a book of this date would almost certainly specify a boiling-water or oven process, in which the jar contents top out around 212F. No amount of extra time at 212F substitutes for pressure.
- No process specified at allThe instructions are entirely by cross-reference: "finish precisely the same as asparagus, cooking the same length of time." A canning procedure with no stated temperature, pressure, or duration on the page cannot be evaluated or reproduced, which is by itself reason enough not to attempt it.
- Raw pack in cold waterFilling jars with cold water and unblanched beans means the jar starts cold and dense. Starch-heavy beans pack tightly and slow heat penetration to the centre of the jar, so the interior lags well behind the outside and may not be held long enough at temperature even during an extended boil.
- Toxin you cannot detectBotulinum toxin does not reliably announce itself. A spoiled jar may swell or smell sour, but it may also look, smell and taste entirely normal. There is no inspection step that makes this method acceptable.
- If you want canned limasUse a current pressure-canning process from a tested source, with the jar size, headspace, pressure and time all specified for your altitude. Freezing blanched limas is the simpler route and needs no special equipment.
Recipes like this one are a snapshot of the moment when home canning had become a national enthusiasm but the science had not caught up. Glass jars with reliable closures made putting up vegetables feasible for ordinary households from the later nineteenth century onward, and cookbooks of the period are often said to have treated all vegetables alike: pack, cover with water, seal, boil for some stated stretch of time. The distinction that governs all modern practice, between high-acid foods that boiling water can safely process and low-acid ones that require pressure, was worked out through bacteriological research in the early twentieth century, and pressure canners only became common household equipment considerably later. Instructions of this kind, chained by cross-reference from one vegetable to the next, are also a reminder of how compressed these books were, with one entry presumably carrying the method and everything else simply pointing at it.