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How to: Table Olives

Table Olives – Safe Methods for home pickling by the University of California

TABLE OLIVE RECIPES

by Stan Kailis
University of Western Australia

Traditional Method

  • Olives can be pickled when green or black. A black olive is simply a ripe olive. Generally the green olives are used for pickling. Some black olives are used for pickling but in the main they are pressed for oil.
  • Place the olives on a clean stone surface or cutting board and bruise them with another stone or hammer.
  • Alternatively, prick several times with a fork or make three slits in the skin of each olive with a small serrated knife while turning the fruit between the thumb and index finger. This bruising, pricking or cutting will allow the water and salt to penetrate the fruit thereby drawing out the bitterness and also preserving it. This will also do away with the need to use a caustic soda solution as used in commercial processing of olives.
  • Toss them immediately into a bucket of clean water in which one half cup of course or cooking salt has been dissolved into every ten cups of water. A clean plate can be placed on top to keep the olives submerged. All olives must be under the liquid. Pour the liquid away each day and replace with fresh salt water.
  • Repeat this washing process for about 12 days for green olives and about 10 days for black (ripe) olives. The best test is to bite an olive. When the bitterness is nearly gone the olives are ready for the final salting.
  • As you can see this simple recipe involves the disposal of salty water into the environment. If you decide to commercially pickle olives, there are other recipes that require a longer pickling time but do not result in salty waste water.
  • Pour off and measure the last lot of water so that you will know the volume of salt brine that will be required. Measure that quantity of fresh warm water into a pan and dissolve the salt, this time at the rate of 1 cup of salt to 10 cups of water. Bring the salt water preserving mixture to the boil and allow to cool. Place olives in bottles and then pour the salt water brine over them until the fruit is completely submerged. Top up the bottles with up to one centimeter of olive oil to stop the air getting to the fruit and seal the lids on.
  • No further preparation is required and the bottled olives will store for at least 12 months in a cool cupboard.
  • When you are ready to eat your olives, pour out the strong preserving solution and fill the jar with clean, cool water. Leave in the refrigerator for 24 hours and taste them. If they are still too salty for your liking, then refill the bottle with a fresh lot of water and return to the refrigerator for a further 24 hours. (The plain water leaches some of the salt back out of the olives). At this stage you can also add any or all of the following flavourings:
    • Grated garlic; basil; oregano; chopped onion; red capsicum; lemon juice; lemon pieces. Especially popular is a combination of garlic, basil and lemon juice.

Black Dried (Greek style) Olives

  • Choose very ripe olives, handpicked, good quality, unblemished.
  • Wash the fruit and place in a white pillowcase with salt, 1kg of salt to 10kg of olives, and mix well.
  • Hang the bag of olives and turn it end to end each day so the salt will continue to mix evenly. Place a container below the bag to collect the salty juice, and discard the juice.
  • Continue to turn the bag for 15 days and test for a pleasant flavour (not too bitter and a good texture). If the olives are still too bitter, continue the process. You may finally roll them in some extra virgin olive oil to give them a nice shine, or marinate them in your favourite combination of herbs.

Spanish-style Green Olives

  • Olives should be picked when firm and green to straw yellow in colour and handled carefully as bruising causes dark blemishes on the processed olives. One way to avoid bruising is to pick into a bucket of water.
  • Wash the olives in clean water and remove any damaged fruit, leaves and twigs. The olives should be of a uniform size to ensure all fruit is evenly treated and the bitter taste removed.
  • Place the olives in a glass or plastic container and cover immediately with a lye solution. This can be made by mixing:
  • flaked caustic soda (15g / litre of water) … 4 level tablespoons
  •  common salt (15g / litre of water) … 3 level tablespoons

CAUTION: Caustic soda can cause severe skin burns … if you get the mixture on the skin or in the eyes – wash or flush thoroughly with cold running water for at least 10 minutes, and call a doctor. If swallowed administer milk or egg white. Do not induce vomiting. Call a doctor. Never put lye in aluminium or galvanised containers as it will ruin the containers and poison the olives.

  • Rain water or another source of clean, pure water is best for all steps. The salt is added to the lye to prevent the softening of the more mature olives. Once the lye is added keep the olives submerged and away from light. Exposure to air will cause the olives to darken. This must be maintained until near the end of this brining process when the olive’s colour becomes stable. As the lye penetrates the olive the flesh discolours. This can be monitored by simply cutting open and olive.
  • Test at least 5 olives to ensure that on average the correct depth has been achieved. This will take between 8 and 48 hours depending on the olive variety, the size and the degree of ripeness. If the lye has not penetrated to the correct depth after 24 hours, replace the lye mixture.
  • Once the lye has reached the correct depth it has to be leached out od the fruit, so rinse the olives twice with clean water and leave submerged in cold, fresh water. Change the water after 2 hours, ensure that the olives receive no undue exposure to the air. Excess washing should be avoided as it leads to darkening of the fruit and loss of flavour and texture.
  • After the washing is completed, the olives need to be pickled in a series of brines of increasing concentration to prevent “salt-shrivel” which can occur if a single high-strength brine is used. During or after the brining solution, the olives are fermented and the sugars in the olives are converted into lactic acid to give the typical Spanish-style green olive flavour.
  • Before beginning the brining it is best to transfer the olives to the containers in which they will be stored. Used galls or plastic jars of at least one litre capacity.
  • step 1 25g / litre of salt / water 2 days
  • step 2 40g / litre of salt / water 4 days
  • step 3 60g / litre of salt / water 2 weeks
  • step 4 80g / litre of salt / water 3 weeks
  • step 5 80g / litre of salt / water storage
  • During brining and fermentation the olives must be kept submerged. If there is foaming and gas formation during fermentation ensure the brine level is maintained. Fermentation is most rapid at 20C to 30C. Once the gas formation has slowed, the pickling vessels should be closed to exclude air and reduce the growth of yeast on the surface of the brine solution.
  • Sugar may need to be added to achieve the desired level of fermentation … 2grams of sugar per litre of brine at least 4 days after the fermentation has started.
  • Once the containers are sealed, store in a cool place until ready for use. If closely sealing containers are not used, cover the brine with a 5mm layer of olive oil to prevent evaporation. They will keep for at least a year, but may be too salty for use straight from the brine solution, so they may need to be soaked in cold water for 24 hours before use. They will keep for about a week in the refrigerator once freshened up this way.

Kalamata Style

Kalamata Style olives is one of the ways that the Greeks prepare olives.  There are two ways. You can use Kalamata olives, Volos or Hojiblanca

  • Use only one variety/batch. Remove defective fruit, leaves and stalks.
  • Soak for one day to get rid of orchard dust and contaminants. Use good quality water. Use hygienic principles.

Method 1

    • Fresh black ripe olives are placed in brine (8-10%) until de-bittered – Fill containers to the top, and keep olives under the surface.
  • When bitterness has reached an acceptable level, remove and either soak in wine vinegar overnight, then put into fresh brine (8-10%) or make up a brine with vinegar – use 3 parts 10% brine and one part wine vinegar.
  • Then add extra virgin olive oil

Method 2

  • Soak Fresh black ripe olives in water or 2% brine changing the soaking solution daily for 5-10 days. Bitterness should be acceptable. Then soak in wine vinegar or make up brine with wine vinegar as above.
  • Add EVOO.

In summary

  • Method 1 gives a better product. Also you can slit the olives before brining or just before putting them in vinegar. Slits give better penetration of salt and vinegar and help in the de-bittering of the olive.

Olive Processing – a simple method

  • Collect an amount of olives, green, black or turning colour.
  • Either leave the olives whole or slit along the side to make 2 lateral cuts, or tap to break the flesh without hitting the seed. Unbroken olives take longest to pickle, slitted are quicker, broken are quickest.
  • Wash the olives to remove any dust, leaves etc.
  • Pack the olives into a container and add 10% brine (100grams of salt to 1litre of water) to cover the olives. Ensure all olives are below the water level at all times, and fill the container to the brim to exclude any air.
    This process will reduce the bitterness of the olive by leaching into the surrounding solution. A natural fermentation will also occur, so the top of the container will need to be loosened occasionally to allow Carbon Dioxide to escape.
  • The pH of the water will rise as the fermentation progresses, and the salt level will need to be maintained at 10%. This will need to be regularly monitored. If the salt level drops below 6% there is a strong chance of spoilage. Lactic acid can be added to drop the pH if required.
  • Once the fermentation process has stopped, the olives are stable and can be stored in a 10% brine solution, which will prevent spoilage. The olives should still be natural in colour and have a olive / salt flavour.
  • Once you want to bottle the olives, make up a new brine solution at 6% salt, and add 10% vinegar to the mixture. You may need to vary the amount of vinegar to suit personal tastes depending on the strength of flavour and the strength of the acetic acid, which is generally 6% in most vinegar. Use decent quality wine vinegar for best results.
  • Add herbs and spices to taste. Be creative.

Generally speaking, broken olives should become edible in about 6 weeks using this technique; whole olives take up to 3 months or longer depending on their size.

I have found that this is a practical way to process small amounts of olives. You should be able to pick up 20litre food grade buckets with lids fairly easily at hardware shops and the like. A 20litre bucket should hold around 13kg of fresh olives. Sterilise the bucket using Sodium Metabisulphite, available wherever home brew beer kits are sold, rinse and put around 50mm of brine in the bottom of the bucket. This will stop the olives hitting a hard surface and bruising as the go into the bucket. Discard any olives that are bird marked, diseased of otherwise damaged, then simply keep adding olives and brine until you are about 100mm below the top of the bucket.

It is important to be able to keep all the olives below the surface of the brine, so a dinner plate should be about the right size to stop any olives floating to the top. You may need to get creative here! Fill the bucket to the absolute top with more brine and push on the lid, excluding any air. This is very important. This fermentation process is anaerobic, and the presence of air will cause spoilage.

You may get some white yeast forming on top of the liquid once the olives are exposed to air. This is not a problem, so just wash it off.