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Canned Blueberries
Blueberries are canned the same as Blackberries, allowing one half cup water for every four pounds of blueberries. 4 pounds cherries
This is a cross-reference rather than a standalone procedure, and what it points to is a turn-of-the-century canning method that no longer meets any current standard. The notes below explain what the text says and why it cannot be followed.
- No process at allThe entry gives one ratio — half a cup of water to four pounds of berries — and nothing else: no jar preparation, no processing method, no time, no temperature. Everything depends on the Blackberries entry, which is not reproduced here; many canning directions of this period assumed open-kettle filling, in which hot fruit is ladled into hot jars and sealed with no processing in a boiling-water bath. That method is no longer recommended for any product.
- Seal failure is the real riskBlueberries are high-acid fruit, so botulism is not the primary concern here. The concern is that open-kettle sealing produces an unreliable vacuum, and jars that appear sealed can admit air and support mould and yeast growth over months of storage. Spoilage in a sealed jar is not always obvious before the jar is opened.
- Period closuresThe jars in use when this book was printed were glass-lidded wire-bail types with rubber rings, or zinc caps over rubber. Modern two-piece lids behave differently and are not interchangeable with the sealing assumptions behind an instruction this brief.
- The stray line"4 pounds cherries" at the end has no relationship to the blueberry instruction and appears to be a stray fragment from a neighbouring entry rather than an ingredient for this one.
- If you want canned blueberriesUse a current tested recipe from a food-preservation authority, which will specify jar size, headspace, altitude adjustment and a measured boiling-water-bath time. Do not attempt to reconstruct a process from this line.
Berry canning entries in American cookbooks of this period are characteristically terse because the method was assumed rather than taught. Whole runs of recipes were written as chains of cross-references — blueberries like blackberries, and so on down the list. Lowney's, a Boston chocolate manufacturer, published its cook book in that vein, and the preserving chapter reflects a household economy in which a summer's picking of wild low-bush blueberries, a New England staple gathered rather than bought, had to be put up quickly and in quantity. The scientific study of home canning safety, and the extension-service pamphlets that eventually replaced instructions like this one, came later.