Producing large quantities of olive oil for commercial use requires expensive equipment and quite complex work, but it is possible to create a small batch for your own use with common kitchen utensils. The process is long and laborious, but the result is a fresh, clean and high quality oil.
Produces 500 ml of oil.
- 2.5 kg of fresh organic olives;
- 1/2 to 1 cup (125 to 250 ml) of hot water (distilled/filtered before use).
Part 1 of 4: Preparing the Olives
Step 1. Choose ripe or unripe olives
You can use unripe green or ripe black olives for this process, but whatever the type, it's important that they are fresh rather than canned and processed.
Olive oil made from ripe olives offers more health benefits than unripe olives, but the flavor and smoke point are not much different. In addition, the unripe ones produce a greenish oil, while the ripe ones produce a medium golden oil
Step 2. Wash thoroughly
Put the olives in a colander, rinse them under running water and use your fingers to remove the dirt.
- During this step, separate the olives and remove leaves, branches, stones or other residues mixed with the fruit. These elements can ruin the oil and the equipment used to produce it.
- After washing, drain off excess water and pat dry with a paper towel. Fruits don't need to be perfectly dry as the water will separate from the oil, but they should stay dry if you're not going to use them right away.
Step 3. Use within a few days
The ideal is to crush the olives on the same day as harvesting or obtaining them. You can wait two to three days if necessary, but waiting longer than that can diminish the flavor and quality of the oil produced.
- If you need to wait a few days before making the oil, transfer the olives to an open plastic or glass container and refrigerate.
- Analyze the fruits before using them and discard those that appear spoiled, shriveled or soft.
Part 2 of 4: Crushing and pressing the olives
Step 1. Work on shipments if necessary
Even if you are going to make a small amount of olive oil – just 500 ml – you may need to separate an entire shipment into three or four parts, depending on the size of the equipment.
Step 2. Gather the olives in a shallow bowl
Place the clean fruits in a large bowl with relatively shallow sides. Ideally, keep them in a single layer.
For homemade olive oil prepared in your own kitchen, the best option is to use a bowl or similar dish with edges, rather than something completely flat. Although the first round doesn't produce much liquid, the bowl will better collect the liquid that comes out compared to a flat board
Step 3. Grind the olives into a paste
Using a kitchen hammer, strike the fruit repeatedly to create a thick, voluminous paste.
- You can use a meat tenderizer for this step. It is recommended to use the metal or plastic versions, but the wooden ones will absorb some of the liquid. You can use either side of the hammer to crush the olives.
- Remove the lumps while doing this. As they are relatively fragile, you can crush them when creating the dough. This will not have a negative impact on the olive oil, but the stray pieces of the pits can damage the electrical appliances you will need to use in the process, so it is recommended to remove the pits.
- When ready, the fruits should be completely kneaded, and the dough should have a slightly shiny layer on the surface, which is produced by the oil. The crushing process degrades the pulp of the olives, which releases the oil contained within the cells.
Step 4. Transfer the paste to a long glass, filling only 1/3 at a time
- Technically, you can leave the paste in the used bowl, but the next part of the process creates a huge mess, so using a taller-sided glass or dishes helps to reduce some of the unavoidable splashes.
- Another option is to use a spoon to transfer the paste to a durable high-speed blender. Do not fill more than a third or half of the container.
Step 5. Mix the paste with water
Put 2 or 3 tablespoons (30 to 45 ml) of hot water into the cup for each cup (250 ml) of the paste. Quickly mix the contents to distribute the water evenly and let it sink to the bottom of the glass.
- You just need enough water to make it easy to mix; do not add an amount that completely covers the olives.
- The water should be hot but not boiling; the heat helps release more oil from the paste. Ideally, it should be filtered or distilled before use, as unfiltered tap water can introduce impurities into the final product.
- The water you add will separate from the oil later on.
Step 6. Press using an immersion blender
Grind the olive paste further until oil drops begin to form on the surface.
- Continue the process for at least five minutes. Mixing the paste for longer intervals releases more oil from the fruit, but it also increases oxidation, which can result in a product with a shorter shelf life.
- Use a high-powered blender if you haven't removed the lumps; otherwise, the pieces could damage the blades. If you've removed the lumps, a full-powered blender will do.
- You also have the option of using a regular blender for this part of the process, but you'll need to stop and check your progress every minute.
- During professional extraction, this process is known as “thermal blending” and encourages smaller oil droplets to combine to form larger droplets.
Part 3 of 4: Extracting Oil
Step 1. Mix the paste until the oil separates
Using a spoon, vigorously stir the olive paste for several minutes, until the small drops turn into larger drops of oil.
- Try moving the folder in a circular motion. The force of each rotation helps extract more oil from the solid “bagasse” or the husk.
- This Step is also part of the heat-blending process, but instead of using high speed to extract the oil, you use force direction to separate the various components of the paste.
Step 2. Let the mixture rest
Cover the dishes with a cloth, paper towel or lid and let the contents rest for five or ten minutes intact.
At the end of this period, it will be even easier to see the oil drops on the surface of the paste
Step 3. Place a cheese-making tissue over a large colander
The fabric must be twice the size of the strainer. Center the fabric and place the strainer over a large bowl.
- Fine mesh strainers are the best choice for this project, but cheesemaking fabric will trap solids even if you need to use a large plastic strainer.
- If you don't have the fabric, use large pieces of filter paper or a paint filter that has never been used.
Step 4. Place the olive paste on the fabric
Using a spoon, transfer the paste directly to the center of the fabric, including all visible liquid and all solids. Wrap the sides of the fabric over the paste, creating a tight package.
The cheese making fabric must completely cover the entire olive paste. If it's not big enough, separate the folder into smaller batches
Step 5. Place a weight on the package
Use a block of wood or something similar that is heavy enough to exert active pressure on the paste.
- If you are concerned about the hygienic conditions of the weight, wrap it in film before placing it on top of the folder.
- Another option is to place a small bowl inside the colander and onto the olive packet. Fill the bowl with dried beans or a heavy material to apply constant pressure to the package.
Step 6. Allow the liquid to drain
Allow the olive oil, olive juice and water to drain through the cheesecloth and colander for at least 30 minutes. The bowl placed under the colander will collect the liquid.
- Every five to 10 minutes, firmly press the pack with your hands to aid the extraction process.
- When you're ready to move on, the bowl should contain a good amount of liquid, and the solids in the fabric should be relatively dry. You can discard all solids at the end of the draining process.
Step 7. Drain the oil
Place the tip of a syringe just below the surface of the collected liquid. Extract the top layer of liquid, leaving the remaining layers. Transfer this part of the liquid to a separate glass.
- Due to the difference in density, the oil must naturally separate into distinct layers, and the oil layer will rise to the surface of the bowl.
- It may take a little practice to extract the oil without collecting some of the water or juice. Analyze the syringe immediately after collecting the oil; if there are separate layers inside the utensil, expel the water and leave only the top layer of oil.
Part 4 of 4: Storing Oil
Step 1. Put the olive oil in a clean bottle
Place a funnel in the mouth of a clean glass vial and transfer the collected oil into the vial.
- Glass bottles are ideal, and colored ones are even better because the color helps protect the oil from the harmful effects of light. However, if necessary, use a plastic container.
- Any bottle you use should be cleaned with hot soapy water and thoroughly washed and dried before transferring the oil.
Step 2. Close the bottle with a stopper
Remove the funnel before closing the bottle with an appropriately sized stopper or cap.
- The type of material does not matter as long as it creates a very tight seal at the mouth of the bottle.
- Clean the oil from the mouth and side of the bottle in this step. Wipe the drops off with a paper towel and wipe off larger spills with a soapy cloth, followed by a clean damp cloth and finish with a dry towel.
Step 3. Store in a cool, dry place
Olive oil is ready to use. Store the bottle in the pantry (or in another cool, dark, dry place) until ready to use the prepared oil.