Important: Safety Warning
This page describes home-canning methods from before the causes of botulism were understood. Canning low-acid foods without a pressure canner, as described here, can allow the growth of Clostridium botulinum, whose toxin is among the deadliest known. Follow current USDA home-canning guidelines instead.
This information has been left in for historical purposes but should not be acted upon.
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Canned Tomatoes
The tomatoes must be entirely fresh and not overripe; pour over them boiling water, let stand a few minutes, drain off, remove the skins, and slice crosswise into a stone jar, cutting out all the hard or defective portions; cook for a few minutes in their own juice, skimming off the scum which rises, and stirring with a wooden spoon or paddle; have the cans on the hearth filled with hot water; empty, and fill with hot tomatoes; wipe moisture from tops with soft cloth, put on and secure covers. If tin cans are used, press down covers, and pour hot sealing wax into grooves. If put up in glass, set away in a dark place. Either tin, glass or stone cans may be used, and all may be sealed with putty instead of wax, it being more convenient. (See general instructions for canning fruit.)
This is open-kettle canning: hot food into hot containers, sealed and set aside with no processing of any kind. It was standard practice for decades and it is the single method modern canning guidance rules out entirely. The notes below explain what specifically goes wrong here rather than how to adapt it.
- No heat process at allThe jars are filled with hot tomatoes and sealed, and that is the end of it. Nothing brings the sealed container to a sustained temperature that would destroy spores or the organisms that survive on the rim, the cloth and the cover. Any survivors sit in a sealed, oxygen-poor jar, which is precisely the condition Clostridium botulinum requires.
- Tomatoes are borderline, not safely acidTomatoes hover around the pH 4.6 line that separates acid from low-acid foods, and some varieties, along with overripe or blossom-end fruit, can fall on the wrong side of it. Current guidance requires added bottled lemon juice or citric acid in measured amounts plus a timed process; this recipe has neither, and the instruction to trim "hard or defective portions" acknowledges damaged fruit without addressing the decay that comes with it.
- Sealing wax and puttyWax poured into grooves and putty pressed round a lid form a seal you cannot inspect and cannot test. Some period putty was made up with white lead, and the side seams of period tin cans were closed with lead solder, putting lead in contact with an acidic food over months of storage.
- Stone jars and unlined tinThe recipe cooks and stores in stoneware and offers tin as an alternative. Some period glazes were lead-bearing, and unlined tin reacts with tomato acid. Neither can be sterilised or sealed to any standard a modern cook could verify.
- Filling cans on the hearthThe recipe warms the cans with hot water on the hearth before filling. Hot water short of a sustained boil does not sterilise, and "wipe moisture from tops with soft cloth" reintroduces whatever the cloth carries directly onto the sealing surface.
- Botulinum toxin gives no warningUnlike ordinary spoilage, botulinum growth in a jar of tomatoes can leave the contents looking, smelling and tasting normal. There is no inspection step that makes a jar put up this way trustworthy, which is why the method cannot be salvaged by care or cleanliness.
- If you want canned tomatoesUse a current tested recipe from a state extension service or the USDA, which will specify added acid, headspace, and either a boiling-water or pressure process with a stated time for your altitude and jar size.
The Dixie Cook Book belongs to the great wave of American household compendiums published in the decades after the Mason jar and the domestic tin can made home preserving plausible for ordinary kitchens, and its canning chapter reads like a survey of every vessel a Southern household might already own: glass, tin, stoneware. Open-kettle canning of the kind described here was widely taught in the period, appearing in cookbooks and agricultural papers alike, because the reasoning behind it seemed sound: boiling food poured into a hot sealed container ought to keep. The name botulism derives from earlier nineteenth-century European work on sausage poisoning, while the causative organism was isolated in the 1890s, and the specific danger of home-canned low-acid vegetables was not widely understood in American households until the extension-service campaigns of the 1910s and 1920s, which is when pressure canners and timed processes began to displace wax and putty. The instruction to store glass jars "in a dark place" is a genuine and lasting piece of advice, though for a different reason than safety: light fades the colour of preserved tomatoes and degrades their flavour over a winter on the shelf.