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Canned Raspberries
6 quarts berries 1 quart sugar Put one quart of the fruit in the preserving kettle; heat slowly, crushing with a wooden potato masher; strain and press through a fine sieve. Return the juice and pulp to the kettle; add the sugar; stir until dissolved; then add the remaining quarts of berries. Boil ten minutes, counting from the time they begin to boil. Skim well while boiling, and put into jars as directed.
This is an open-kettle preserve: the fruit is cooked, ladled hot into jars, and sealed with no further processing. The proportions are sound, but the sealing method behind "put into jars as directed" is the part that no longer stands.
- Why it failsBoiling the fruit sterilises the fruit, not the jar rim, the lid, the ladle or the air that enters as you fill. Open-kettle canning was standard practice for a century and is now rejected because the seal it produces is unreliable and unverifiable; jars can appear tight and still admit air within weeks.
- What actually spoilsRaspberries are high-acid, so the hazard is not botulism but mould and osmophilic yeast, which ferment sweet fruit and push lids off. Some fruit moulds also produce mycotoxins that survive a later cooking, so a mouldy jar cannot simply be skimmed and used.
- No processing figures at allThe recipe gives no headspace, no water-bath time, no jar size and no way to confirm a vacuum. Those numbers are the whole of the safety margin in modern canning, and they cannot be reconstructed from "as directed." Use a current tested water-bath recipe for raspberries instead.
- Jar hardwareJars of this period typically sealed with a screw-on zinc cap over a rubber ring, the caps re-used from season to season and the rings meant to be renewed. Nothing in a modern two-piece lid behaves the way that closure did, so following the original steps with today's jars compounds the problem rather than fixing it.
- A quart of sugarSugar was routinely measured by volume in this period. A quart is 4 cups, roughly 1 lb 12 oz of granulated sugar, against about 8 lb of berries — a light sweetening by preserving standards, which is another reason the pack depended on a good seal rather than on sugar for keeping.
- The ten minutesTen minutes at a full boil is enough to break down most of the berries and drive off much of the volatile raspberry aroma. The crushed-and-sieved first quart plausibly serves to supply thick juice so the whole batch has some body and does not scorch while that happens.
Loose-leaf cook books like Mrs. Fryer's were sold as binders so a housewife could add pages and clippings as she went, and their canning sections read as the tail end of a long era when the summer fruit crop was preserved at home in a single hot week. Open-kettle filling — cook the fruit, fill the jar, screw down the cap — was an ordinary American method well into the twentieth century, and it is most likely what "put into jars as directed" points back to. Raspberries were a favourite candidate because they are fragile, ripen all at once, and travel badly, so a household with canes in the yard had little reason to delay processing them. Crushing and sieving one quart to make a syrup base for the rest appears intended to keep the remaining berries intact: the pulp gives the boil enough body that the fruit poaches rather than sticks. Government extension work through the 1910s and 1920s pressed home canners toward timed water-bath processing, and open-kettle canning was gradually dropped from official guidance over the decades that followed.