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Oysters, Ketchup Of
Take half a pint of fresh oysters, clean them well, carefully removing the eye and the gut, and boil them gently with their liquor until all the goodness is drawn out of them. Strain them, and put the liquid into a clean saucepan, with an equal quantity of light wine, six anchovies, a tea-spoonful of lemon-juice, a quarter of an ounce each of pounded cloves and mace, and a dozen peppercorns. Boil a quarter of an hour longer, then put a dozen shallots and the thin rind of a small lemon into a jar, pour over them the hot liquid with the spices, and when cold bottle the ketchup and resin the corks. This ketchup is for flavouring sauces when oysters are out of season. Time, half an hour to boil the oysters. Probable cost of oysters, 1s. 6d. to 3s. per dozen.
This is a shelf-stable seafood preserve made without any measured acid, salt or heat process, and it cannot be reproduced safely. The notes below explain the failure and gloss the older language.
- The core problemOyster liquor combined with wine and spices is a low-acid, moist, oxygen-poor medium — exactly the conditions in which Clostridium botulinum spores germinate and produce toxin. Sealing the cork with resin makes the interior more anaerobic, not more sterile, and the boiling described nowhere approaches spore-killing temperature.
- No measured acid or saltA teaspoonful of lemon juice in roughly a pint of liquid does nothing measurable to pH, and no salt quantity is given at all. Modern shelf-stable condiments rely on a documented pH or a validated retort process; this recipe has neither, and the safety of a batch cannot be judged by taste or smell.
- Shellfish specificallyRaw oysters also carry Vibrio species and norovirus. Adding a dozen whole shallots and lemon rind to the jar after the liquid has boiled reintroduces surface organisms into a container that will then be sealed and kept for months.
- Storage assumptionThe stated purpose — flavouring sauces "when oysters are out of season" — means the bottles were meant to keep in a larder for several months. Nothing in the method supports that. If you want a bottled oyster or fish seasoning, use a current tested recipe.
- "Light wine"A pale, unfortified table wine rather than a fortified one such as sherry or Madeira; at ordinary wine strength it carries no preservative value here.
- "Resin the corks"Corks were dipped in molten resin or sealing wax to exclude air, a common nineteenth-century closure for bottled sauces before crown caps and screw bands.
- "Removing the eye and the gut"The "eye" is usually taken to mean the tough adductor muscle, and period instructions to remove it along with the dark digestive parts before cooking are not unusual, though practice varied. Modern practice generally leaves the oyster whole.
- The half-hour boilWorth noting as period evidence rather than technique: oysters cooked this long are being deliberately spent for their flavour, which is why the recipe strains them out and discards the flesh. Oysters served as oysters need barely two minutes.
Before commercial sauce bottling, an English kitchen kept its own line of "ketchups" — mushroom, walnut, cockle, oyster — thin brown seasoning liquids closer to modern Worcestershire or fish sauce than to anything tomato-based. The word itself is generally traced to a Southeast Asian fermented fish brine, borrowed into English in the late seventeenth century, and for a long stretch of that history an unqualified "ketchup" in a British recipe generally meant mushroom. Oyster ketchup existed for a practical reason spelled out in the last line: the oyster season ran through the cold months, and a cook who wanted oyster flavour in a fish sauce in July had to have laid some down. Cassell's price note — 1s. 6d. to 3s. a dozen — fixes what oysters cost in Britain at the time, drawn from beds that overfishing and pollution would go on to damage severely.