Important: Safety Warning
This page directs the use of hazardous substances — such as benzine, gasoline, lye, or strong acids — for household tasks. These materials are highly flammable, corrosive, or poisonous, and the practices described have caused fires, burns, and poisonings.
This information has been left in for historical purposes but should not be acted upon.
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Olives, Preserving Of
Olives intended for preservation are gathered before they are ripe. The object of pickling them is to remove their bitterness and preserve them green by impregnating them with brine. To effect this various plans are adopted. The fruit being gathered is placed in a lye composed of one part of quicklime to six of ashes of young wood sifted. It is left for half a day, and is then put into fresh water, which is renewed every twenty-four hours. From this the fruit is transferred to a brine of common salt dissolved in water, to which some aromatic herbs have been added. Olives will in this manner keep good for twelve months.
This is the traditional lye cure for green olives, described in a form that gives no strengths, no timings that can be checked, and no way to know when the caustic has been washed out. It cannot be followed safely.
- The lye is unmeasured and uncontrolledQuicklime (calcium oxide) slaked with water becomes calcium hydroxide, and sifted wood ash yields potash, which with the lime gives a hydroxide solution of wholly unknown strength depending on the wood and the burn. "One part to six" fixes the ratio of the two solids but says nothing about how much water, so the resulting solution could be anywhere from mild to severely caustic.
- No test for when the caustic is goneModern lye-cured olives are washed and soaked until the flesh tests neutral, and the fruit is checked to see how far the lye has penetrated. "Fresh water renewed every twenty-four hours" with no endpoint leaves the possibility of alkali retained in the fruit, which burns the mouth and throat.
- Quicklime is a burn hazard before it ever reaches the foodSlaking quicklime releases considerable heat and can spatter. The dry powder and the resulting solution both attack skin and eyes, and neither food-grade purity nor consistent composition can be assumed of hardware-shop lime.
- The brine strength is not givenOlive storage brines are held at a specific salt concentration and acidity precisely because the finished fruit is a low-acid food kept for months at room temperature. "Common salt dissolved in water" is not a specification, and an under-strength brine on a low-acid vegetable at ambient temperature is exactly the condition under which Clostridium botulinum is a real concern.
- Twelve months at room temperatureThe keeping claim comes with no storage conditions and no brine strength. Nothing in the text lets a modern reader reproduce the conditions assumed or recognise a failed batch before eating it.
- What to do insteadOlive curing is still done at home, but use a current recipe that specifies lye concentration by weight, neutrality testing, and measured brine salt and acid levels.
Green olives are inedibly bitter from oleuropein, and an alkali soak is the fastest way to break it down — the method is generally traced to Mediterranean and especially Spanish practice, and survives as the "Spanish-style" or Sevillano cure behind most commercial green table olives, where food-grade sodium hydroxide has long since replaced lime and wood ash. Before manufactured lye was cheap and standardised, household alkali commonly came from the two sources named here: burnt limestone and the ashes of the fire, which is why the same pairing turns up in soapmaking, laundry and hominy.