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String-Beans
String fresh string-beans, break in several pieces, cook in boiling water ten minutes, and can like tomatoes. - Mrs. L. W. C., Cincinnati.
This is a home-canning instruction, and it is the one category of nineteenth-century cookery that modern food science has overturned completely. The problems are with the method itself, not with the beans.
- Green beans are a low-acid foodBeans sit around pH 5.6, well above the 4.6 threshold below which Clostridium botulinum cannot grow. Tomatoes, the model the recipe points to, are acidic; beans are not, and the two cannot be processed the same way.
- Boiling water does not kill the sporesTen minutes in boiling water, and any water-bath processing that follows, reaches 212F at most. Botulinum spores are highly heat-resistant and are not reliably destroyed at that temperature. Sealed in a jar, they find exactly the oxygen-free, low-acid, room-temperature conditions they need to germinate and produce toxin.
- The toxin is invisibleSpoiled jars of home-canned beans have historically looked, smelled and tasted normal. There is no sensory check that makes this method safe, and home-canned low-acid vegetables, green beans among the most frequently implicated, account for most foodborne botulism cases in the United States.
- "Can like tomatoes" gives no process at allThe recipe specifies no jar size, no processing time, no temperature and no headspace. Even setting aside the acidity problem, there is nothing here to follow.
- What to do insteadLow-acid vegetables require a pressure canner at a validated temperature and time for the jar size and altitude. Use a current tested process from a food-safety authority rather than adapting anything on this page. Freezing blanched beans is the other straightforward route.
Recipes like this one are a snapshot of the moment when home canning became a mass domestic practice and before anyone understood what could go wrong. The screw-band glass jar patented by John Landis Mason in 1858 put sealed preserving within reach of ordinary kitchens, and community cookbooks such as this one filled with contributed methods that were passed along on the strength of one household's experience. Clostridium botulinum was not identified until Emile van Ermengem's work in the 1890s, and pressure processing for low-acid vegetables did not become standard advice in the United States until well into the twentieth century. The instruction to treat beans "like tomatoes" is the whole error in four words: to a cook of the 1880s, canning was canning, and the distinction between an acidic fruit and a low-acid vegetable had no meaning yet. The contributed initials and city, common throughout The Dixie Cook Book, mark this as one neighbor's kitchen practice rather than tested guidance.