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Canned Strawberries (Fill glass jars with fresh)
Fill glass jars with fresh whole strawberries, sprinkled with sugar in the proportion of half pound sugar to a pound of berries, lay covers on lightly, stand them in a wash boiler filled with water to within an inch of tops of cans (the water must not be more than milk-warm when the cans are placed in it). When it has boiled for fifteen minutes, draw to back of stove, let steam pass off, roll the hand in a towel, lift out cans, and place on a table. If the berries are well covered with their own juice, take a table-spoon and fill up the first can to the very top of the rim from the second, wipe the neck, rub dry, and screw the top down firmly, observing carefully the general directions for canning berries. Fill another from the second can, and so on until all are finished. Great care must be taken to keep the berries whole and round; as the cans cool invert them occasionally, to prevent the fruit from forming in a mass at one end.
This is an open-kettle-style method with the jars sealed after heating, and it fails on every point that modern canning practice is built around. The notes below explain what goes wrong rather than how to fix it.
- The seal is made after processing, not duringThe jars are lifted out, topped up from a neighbouring jar, wiped, and only then screwed down. Every one of those steps reintroduces airborne yeasts, moulds and bacteria into hot fruit, and the vacuum that forms as the jar cools traps them inside. A tested process seals the jar before heat is applied and never opens it again.
- The water never covers the jars"Within an inch of tops of cans" leaves the headspace and the lid area below the temperature of boiling water. Current boiling-water canning requires one to two inches of water over the tops of the jars for the whole timed period, so that the coldest point in the jar reaches processing temperature.
- Topping up from can to canTransferring juice between jars with a spoon after heating reintroduces contamination into hot fruit, and it also destroys the measured headspace that a reliable vacuum seal depends on. Filling to "the very top of the rim" leaves little or no headspace.
- Inverting the cooling jarsRolling the jars over to keep the berries evenly distributed drags fruit and syrup across the sealing surface while the lid is still setting. Inversion is not part of any current tested method and can disturb a seal that has not yet formed.
- What the risk actually isStrawberries are high-acid, so Clostridium botulinum is not the primary danger; the realistic outcomes are mould, yeast fermentation and spoilage organisms in a jar that looks sealed. Mould growth in high-acid preserves can also raise the pH locally over time, which is why spoiled fruit jars are discarded rather than skimmed.
- No processing time you can rely onFifteen minutes counted from an unspecified starting temperature, in a wash boiler of water that began "milk-warm" and with the jars only partly submerged, is not a measurable heat process. There is no way to state a corrected time for this configuration, because the configuration itself is wrong.
- Historical terms, for readingA wash boiler is the large oval tin or copper vessel used for laundry on a range top, deep enough to stand quart jars upright. "Milk-warm" means roughly blood heat, about 95-100F, and the caution against hotter water most likely reflects the fragility of period glass, which could crack under thermal shock.
- If you want canned strawberriesUse a current tested recipe from a reliable canning authority. Whole berries in light syrup and strawberry preserves both have modern processes with specified headspace, timings and jar handling.
Buckeye Cookery and Practical Housekeeping came out of Ohio in the late 1870s, at a time when the screw-top glass fruit jar had become cheap enough for ordinary households and home canning was spreading beyond specialist practice. The book's canning chapter reads as a set of workarounds for equipment its readers actually owned: the laundry boiler doubling as a processing kettle, the towel-wrapped hand instead of a jar lifter, the warning to start with barely warm water because thick, unevenly annealed jars could split when shocked. The insistence on whole, round berries suggests that the appearance of preserved fruit mattered as much as its flavour. Half a pound of sugar to a pound of fruit is one of the common nineteenth-century proportions for canned fruit, sugar being valued then for its preservative effect as much as its sweetness. What the recipe cannot show is any grasp of microbiology; the germ theory of spoilage was still working its way into domestic manuals, and the assumption that a jar sealed while hot was a jar made safe.