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Raw olives are olives that have been harvested from the tree but not yet cured. Olives are typically grown in areas with Mediterranean-like climates, including Greece, Italy, California, Jordan, Israel, South Africa and others, and they are native to the eastern Mediterranean region. Any of the varieties of olives cultivated around the world can be raw.
The curing process renders the olive edible; raw olives are incredibly bitter and not fit for consumption due to a naturally-present chemical called oleuropein. The brining process removes the chemical while preserving the olives and adding flavor. The fruit is typically harvested in the late fall or winter and then processed for preservation.
People have been preserving olives for thousands of years; there are references to olives in many ancient texts, including the Bible and Homer's Odyssey. The fermentation process used can be done in a factory or at home in small batches. Olives can be processed at almost any stage of their development, from green to fully ripe. The best are selected for their firmness before processing and then washed.
The raw olives are slit and then added to a solution that helps remove the bitter compounds from the fruit. This solution varies from method to method but can include lye, salt or vinegar. The olives are soaked and cured for anywhere from two weeks to three months. Other preservation methods include salt curing and water curing; all methods result in fermentation.
The brining process ferments the fruit and leaches out the bitter oleuropein and other chemicals called phenols. It also brings about the production of lactic acid, which aids in the fermentation process because it is a naturally-occurring preservative. After the olives are brined, they can be flavored with garlic, marinades, vinegar or oils. They also can be stuffed with pimentos, cheese or anchovies, among other ingredients.
Olive oil uses raw olives, but more care is given to determining the right time to harvest the fruit. Ones used for olive oil must be harvested when the olives are perfectly ripe in order to create an oil that is neither too bitter nor rancid. The olives are selected and then crushed to produce virgin oil. For lower grade oils, they are pressed a second time.
A number of countries consume olives as a staple food, but their widespread popularity has led to the fruit being one of the most cultivated foods in the world. Cured olives and olive oil contain a number of heart-healthy compounds, including monounsaturated fats. Studies have shown that olives also have antioxidant properties.
I didn't know that raw olives are used for olive oil. Is this why some olive oils turn rancid quickly?
I had a bottle of virgin olive oil from Italy that turned rancid after a few months.
I don't understand why raw olives aren't treated to get rid of the bitterness before they are crushed. Anyone know why they make olive oil this way? I suppose one reason might be for nutrition and vitamins. I know raw olive oil is very healthy and nutritious.
@anamur-- I don't know if there is a best way to cure olives, there are just different ways.
My mom lives in Greece and she cures her own olives. Sometimes she does it with salt and sometimes with vinegar but salt is her favorite way. The olives come out really good after salt curing. They're not bitter and they're not too soft or too hard.
I don't know the exact process but I think she just puts the raw olives in a huge closed container with lots of salt. She keeps it like this for several months and shakes the container every couple of days to redistribute the salt.
I've also seen her leave the olives in
water first before curing them. I think she does this when the olives are particularly bitter. She lives them in a container with water for a week, and then throws out the bitter water and adds fresh water. She does this once a week for about a month before she adds vinegar or salt.
Curing raw organic olives is hard though, it's kind of a hit or miss even if you get the method right.
What's the best way to cure raw olives?
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