Real Food Encyclopedia | Olives

Olives have long had a place in our kitchens and at our tables. To the Greeks and Romans, the olive wasn’t just a source of food, but the fuel that lit their lamps and bolstered their economies.

To this day, to figuratively extend the olive branch means to offer peace to your enemy. Learn more about the hearty olive, which not only tastes great but is good for you too!

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Fun Facts about Olives:

  • As a member of the Olea genus, the olive tree is related to lilac, forsythia and jasmine.
  • The olive is a type of a fruit known as a drupe, which contains a pit or stone surrounded by the flesh of the fruit.
  • One of the oldest known olive trees still alive and still bearing fruit is located on the Greek island of Crete. It is estimated to be between 2,000 and 3,000 years old.

What to Look for When Buying Olives

Table olives are sold in shades of green, purple, black and even red. Some have had the pit removed before consumption as well. But it’s the purple or black olive that has been picked when ripe. Green olives are unripe and must be treated with a solution of lye to get rid of the bitter-tasting compound oleuropein before consumption. Olives with pits tend to have a more pleasing, firmer texture as well as a better taste.

When it comes to olive oil, see if you can find a bottle with a date on it and then look for something that was bottled recently. Also look for dark glass or cans since the quality of the oil is degraded by light. If your olive oil is “extra virgin” it means that it is of the highest quality — low acidity and free from additives, adulteration and “sensory defects.” While olive oil must pass quality control tests to be deemed extra virgin, 69 percent of brands tested failed to hold up to US and international standards in a recent joint study between the University of California, Davis and the Australian Olive Association.

There are lots of terms used on olive oil bottles that do not necessarily mean much, including “pure,” “natural,” “virgin olive oil,” “premium,” “light,” “made in Italy,” and just “olive oil.” If you have the opportunity to buy a California olive oil or an artisanally produced olive oil from Spain or Italy, you avoid these issues.

Sustainability of Olives

Like all industrially produced crops, the olive industry contributes to agricultural runoff, soil depletion and overuse of fertilizers and water. In Spain, where olive production is big business, irrigation has put strain on groundwater in Andalusia, bringing agricultural practices into question. And Spain is a country where 85 percent of its water is used to grow crops. It takes 363 gallons of water to make a pound of olives while 1,902 gallons are in a half liter bottle of olive oil. Better water management and use of olive byproduct for fertilization are just a couple of the recommendations to bring sustainability to the industry.

As of now, olives have mostly escaped genetic modification. Researchers in Italy experimented with fungal and bacterial resistant crops, but laws banning GMO field research have halted further development.

Olive Seasonality

In the US, olives are in season in the autumn and harvest occurs from September into November. Ripe olives are purple and black depending on variety. Even when ripe, though, olives are too bitter to eat as a fresh fruit. The ones you are used to eating have been “cured,” by being soaked in brine or salted. Although canned black olives (those found on a supermarket shelf) are actually green ones that were turned black with alkaline.

Olives and Geography

Spain and Italy are top producers of olives in the world while in the US, California produces 99 percent of all domestic olives.

The olive is the fruit of an evergreen tree that can grow up to 30 feet tall. The tree, with its characteristic silvery green leaves and gnarled bark, thrives in hot, sunny Mediterranean climates. Although it grows well in moist soil, olive trees are fairly hearty when it comes to drought resistance, flourishing in the rocky and often steep hills along the Adriatic. Trees can also hold up to cold snaps, but will die off in freezing temperatures. If you are thinking about planting an olive tree, know that it can take up to fifteen years for it to bear fruit.

Olive production is separated into two parts: table olives (olives grown for cooking and eating) and olive oil. While most of the olives grown in the world are turned into oil — about 90 percent — most of the table olives are consumed in Mediterranean and Middle Eastern countries, according to “The Oxford Companion to Food.”

It takes about seven pounds of olives to make a half liter bottle of olive oil. The ripe olives are ground into a paste that is then pressed. The resulting liquid is then separated by centrifuge into oil and a liquid called pomace. In ancient times, the process involved stone mills to crush the olives and grass mats to separate the liquid.

Eating Olives

Storing Olives and Olive Oil

Olive oil has a limited shelf life and should be consumed within a year of production otherwise it will go rancid. When not using, store in a cool place out of direct sunlight. Fresh, cured olives will keep in the refrigerator for at least a few weeks, while canned and bottled olives can last years if sealed and kept cool (and away from direct sunlight).

Cooking with Olives

It’s hard to think about olives without thinking about olive oil, especially when 90 percent of harvest gets turned into oil. It can be used to cook with, drizzle on seasonal vegetables or add to salads.

Table olives are a perfect snack or appetizer, pairing well with various cheeses and wines. Some olives come stuffed with lemon, almonds, cheese and garlic, or seasoned with herbs and chili. A classic olive condiment is tapenade, a puree of black olives, capers, anchovies, herbs, lemon, mustard and even cognac. And don’t forget the olive when making a martini! Cooking with olives and need to remove the pit? Smash the flat side of a chef’s knife et voilà!

Olive oil is also delicious in baked goods, like this classic Italian olive oil cake.

Preserving Olives

Olives are one of the original preserved foods. Humans have been curing, brining, fermenting and salting olives for millennia. In modern times, olives are tinned and bottled, extending their shelf life for years. If you’re one of the lucky few who have ready access to fresh olives, here’s a how-to guide for curing your own.

Olive Nutrition

Olives may be high in fat, but it’s healthy monounsaturated fat. Further, olives are an excellent source of Vitamin E, providing 25 percent of your daily recommended value in a 3.5 ounce serving. In addition, there are a lot of health claims about the benefits of olives and olive oil.