How to Cure Olives

Curing olives is an ancient technique used to transform bitter olives into a tasty snack with a harmonious balance of sour and salty flavors. Your task is to choose the right curing method depending on the type of olives you have. Curing with water, brine, dry curing, or using an alkaline solution will result in different flavors. Olive curing requires patience, but with your own hands, you can achieve the exact taste you desire.

Prepare green olives. Curing olives in water helps to remove oleuropein – the compound responsible for the bitter taste in olives. Green olives are unripe (like green tomatoes) and have a milder flavor, so water alone will suffice for the curing process.

• If green olives are left to ripen on the tree, they will turn purple or black. Once ripe, water will not be enough to eliminate the bitterness; a different method will be required.

Inspect the olives. Make sure that the olives are not damaged. Check for any bites from insects or birds. If the olives have been chemically treated, it's a good idea to wash them thoroughly before curing.

Crack the olives. To allow the water to soak into the fruit, you need to crack the olives. This can be done with a wooden mallet or a rolling pin. Gently tap to avoid crushing the olives too much. It's important not to break them into pieces or damage the pit.

• If you're concerned about damaging the shape of the fruit, you can use a sharp knife to make three slashes in the flesh to help the water penetrate inside.

Place the olives in a plastic container and cover with cold water. Use a food-grade plastic container with a lid. Make sure the olives are fully submerged in water. You can weigh them down to ensure they stay immersed. Cover the container loosely and store it in a cool, dark place.

• Tip: Make sure to use a food-grade plastic container to prevent chemical components from leaching into the brine. Glass jars are also fine, but make sure to keep them out of direct sunlight.

Change the water. Change the water at least once a day, using fresh, cold water. It's important to do this regularly to prevent bacteria from growing and spoiling the olives. To change the water, you can pour the olives into a strainer, clean the jar, return the olives to the jar, and fill it with fresh cold water.

Repeat the process for one week. After a week of daily water changes, taste one of the olives to see if it has reached your desired bitterness level. If you prefer them to be less bitter, continue changing the water for a few more days before moving on to the next step.

Prepare the brine solution. This will be the mixture used to preserve the olives. The solution consists of salt, water, and vinegar, which not only help preserve the olives but also give them a delicious sour taste. To make the brine for olives (enough for 4.5 kg of olives), combine the following ingredients:

• 4 liters of cold water
• 1 1/2 cups of coarse salt
• 2 cups of white wine vinegar

Drain the olives and place them in jars. You can use a large glass jar with a lid or any other container you have available. Be sure to wash and dry the container thoroughly before adding the olives. Leave about 3 cm of space near the top for proper sealing.

Pour the brine over the olives. Fill the jar with the brine until the olives are fully submerged. Seal the jar and store it in the refrigerator.

• You can add lemon peel, rosemary, roasted garlic, or black pepper to customize the flavor to your liking.
• Olives prepared this way can be stored in the refrigerator for up to a year.

Prepare fresh olives. Both green and black olives can be cured in a brine solution made of salt and water to preserve the olives and create a salty flavor. This method takes longer than water curing, but it’s ideal for ripe olives. Varieties such as Manzanillo (Spain), Mission (USA), and Kalamata (Greece) are commonly used for brine curing.

• Inspect the olives to ensure there are no damaged ones. Remove any with bites from insects or birds. If the olives have been chemically treated, wash them thoroughly before curing.
• You can sort the olives by size. A batch of olives will cure more evenly if all the olives are of a similar size.

Cut the olives. To allow the brine to soak into the fruit, make a slit along the length of each olive using a sharp knife. Be careful not to cut into the pit.

Place the olives in a sealed glass jar. The olives should be stored in a jar with a tight-fitting lid, and a glass jar is the best option. Leave about 3 cm of space at the top of the jar.

Pour the brine over the olives. Dissolve 3/4 cup of salt in approximately 4 liters of cold water. Pour the brine into the jar, ensuring the olives are fully submerged. Seal the jar and store it in a cool, dark place, such as a pantry or cellar.

Wait for 1 week. During this period, the olives will begin absorbing the brine. Keep the jar in its storage location to allow the saltwater to penetrate the olives.

Drain the olives. After one week, remove the olives from the brine and discard the salty liquid (which will be very bitter at this point). Place the olives back in the jar.

Soak the olives in a stronger brine. Dissolve 1 1/2 cups of salt in 4 liters of water. Pour this concentrated brine into the jar, ensuring the olives are fully submerged. Seal the jar tightly.

Store the olives in the jar for 2 months. Keep the jar in a cool place, away from direct sunlight. After 2 months, taste the olives to check if the bitterness is to your liking. If not, change the brine and let them soak for another month or two. Repeat this process until the olives reach the desired flavor.

Prepare ripe olives. Black, oil-rich olives are ideal for dry salting. Varieties like Manzanillo, Mission, and Kalamata are commonly used for this method. Make sure the olives are fully ripe and dark in color. Inspect the olives for any damage and discard those with signs of insect or bird damage.

Wash the olives. If the olives have been chemically treated, it is best to wash them thoroughly before salting and then let them dry completely.

Weigh the olives. Use a small scale to get the exact weight of the olives. You'll need about 0.5 kg (1 1/2 cups) of coarse salt for every kg of olives.

Prepare the salt container. You can use a wooden fruit crate with a depth of about 15 cm and two openings on either side. Line the entire inside of the crate with burlap, including the sides, and secure it with nails or staples at the top. Prepare a second crate in the same manner.

• Alternatively, you can line the crate with loosely woven fabric, an old bedsheet, or a towel, as long as the material can hold the salt inside to absorb the draining liquid.

Mix the olives with the salt. Combine 1 1/2 cups of coarse salt with 1 kg of olives in a large bowl. Stir thoroughly to ensure all the olives come into contact with the salt.

• Do not use iodized salt, as it will affect the flavor of the olives. You should use either coarse salt or kosher salt.
• Don’t use less salt, as it won't be enough to prevent mold from developing.

Transfer the mixture into the wooden crate. Pour all the olives and salt into one crate, then cover the top with a layer of coarse salt. Cover the top with some loose fabric to keep insects out.

Place the wooden crate in a sheltered outdoor area. You can place the crate on a tarp, as the liquid from the olives may leak out and stain the ground. Additionally, instead of placing the crate directly on the ground, it's better to put it on top of a few wooden planks to ensure proper airflow.

Stir the olives after one week. Transfer all the olives and salt into a clean container. Shake the container to mix the olives and salt evenly, then gently pour everything back into the original container. This step ensures that all olives are fully coated in salt and allows you to spot any damaged or spoiled olives. Discard any bad ones as they’re not safe to eat.

• Also, remove any olives that have white, round spots (possibly mold). Mold typically forms at the olive's stem.
• Check carefully to make sure the olives are properly salted. If an olive has both wrinkled and plump areas, reduce the number of olives before soaking them in salt again to help plump up the wrinkled parts.

Repeat the process weekly for a month. After a month, taste the olives to see if they have reached the desired flavor. If they’re still slightly bitter, continue the dry salting process for another 2 weeks. It may take anywhere from 4 to 6 weeks for the olives to fully cure, depending on the size. Once cured, the olives will be a bit wrinkled and softer.

Strain the mixture. You can pour the mixture through a mesh strainer to separate the olives or pick them out one by one from the container, gently shaking to remove excess salt.

Let the olives dry overnight. Spread the olives on paper towels or a cloth and let them dry completely.

Store the olives. Mix 0.5 kg of salt with 10 kg of olives, then transfer the mixture into a glass jar and seal tightly for storage. You can keep the olives in the refrigerator for several months.

• For added flavor, you can also mix the olives with extra virgin olive oil and spices.

Exercise caution when using alkali solution as it can cause burns. It's important to wear chemical-resistant gloves and safety goggles when handling it. Do not use plastic or metal containers for the olives, including the lid, as the alkali solution can dissolve metals.

• Do not apply this method if there are children nearby who could potentially access the olives or the solution.
• Carry out the salting process in a well-ventilated room. Open windows and turn on an exhaust fan.

Wash the olives thoroughly. This method works best with large olives, such as those from the Seville region (Spain). You can use either green or ripe olives. Remove any damaged olives and sort them by size if desired.

Place the olives in an alkali-resistant container. Avoid using metal containers. Glass or ceramic containers are the best options for this purpose.

Prepare the alkali solution. Pour about 4 liters of water into an alkali-resistant container, then add 30 ml of alkali to the water. The solution will immediately heat up. Let it cool to around 18-21°C before adding the olives.

• It’s important to follow the correct procedure of adding alkali to the water, not the other way around, as it could cause an explosive reaction.
• Measure the water and alkali accurately. Too much alkali will harm the olives, and too little will prevent them from curing properly.

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Brine the olives in a mild saltwater solution. Place the olives in a glass jar. Dissolve 6 teaspoons of coarse salt in 4 liters of water, then pour the solution into the jar to fully submerge the olives in brine. Let the olives soak for one week before eating. If kept in the refrigerator, they can be consumed for several weeks.