Green Olives and Black Olives

In my local grocery store all green olives are in jars and all black olives are in cans. Is there a good reason for this? Are there canned green olives and jarred black olives somewhere?

Well, there you go.

I’ve seen green olives in cans (I didn’t actually ***see ***them, since they were in the cans), and I’ve seen black (or purple) olives, usually Greek, in jars.

For what it’s worth, my theory is that black olives are used more for cooking, and so come in cans, since you use them all at once. Green olives are mostly finger food, or used for salads, and so come in a jar with a recloseable lid. The few black olives I’ve seen in jars were expensive and fancy, and were probably marinated in some yummy liquid, and I can only assume they were eaten as finger food one at a time.

In our Greek food section, Kalamata black olives are in jars.

Basically, it is because green olives are raw and black olives are cooked. Green (unripe) olives are processed by being cured with lye and brine. Black (ripe) olives are cooked in the can. Glass jars won’t withstand the heat, so that’s why cans are used.

All the black olives I see in our grocery stores are loose in a bin or barrel, or packed in one of those tupperware-esque resealable plastic containers. If you go for the loose ones, you take a scoop or wooden ladle and an empty plastic container and dish out what you want. Priced by weight. Kalamata, gaeta, oil-cured, etc.

They have green ones like that, too, but also green olives in jars.

I get some specialty green olives in cans, stuffed with garlic, anchovies, or jalapenos. But their texture is much softer than green olives that come in jars, perhaps due to the canning process.

How hot do they cook them, that glass jars won’t withstand the heat?

Oh, green olives in jars are heat processed. Hence the “pop” when you open the lid. They just hold up better because they start out quite firm, whereas black (ripe) olives go into the process already soft.

Do they have speckles on them, if they do they might be ripe green olives.

I don’t know. Several sites mention this, but I haven’t found one yet that goes into much detail about the process.

Several sites mention that green olives are pasteurized, but not cooked at as high a temperature as canned black olives.

No, they are entirely green. Some of the olives in the same can are softer than others. I don’t know whether or not they have been cooked like black olives.

What variety of olives is green when ripe?

Side question: Is olive oil pressed from raw olives or ones that have been brined first?

Olive oil is usually pressed from raw olives. Sometimes they may be brined before pressing in order to preserve them from fermenting. Ripe (black) olives are usually used, and produce a yellow oil. Oil can be pressed from green olives as well, and will be greener in color depending on how unripe the olives were.

I have a hard time believing that. I can vegetables, and glass jars can withstand high heat for prolonged periods just fine - certainly long enough to cook an olive. And since we can now find green in cans and black in glass, I think we need to find a different answer.

Besides which, I can only find a couple of sites which, almost verbatim, say that black ripe olives are cooked and green olives only pasteurized. I think they’re getting their information from one another. The sites I can find on olive varieties don’t mention cooking Black Ripes: here and here and (scroll down) here. Olives are prepared by soaking in lye, salts and Black Ripes by exposing them to air.

The accepted answer when we only had two types of olives in the US supermarket was aesthetics. Back then, you could choose pretty green “Spanish” olives in clear brine, often stuffed with pimentoes, and ugly (but yummy!) black olives in blackish, opaque brine called “Black Ripe” olives. Pretty olives look appealing and you sell more in glass. Ugly cloudy brine should be covered with a can and a pretty picture on the front. Interestingly enough, “Black Ripe” olives aren’t black ripe olives at all, but green ripe olives blackened with oxygen and the blackness retained by added iron.

Now, it’s a little less clear cut, what with Kalamata, Sicilian, Dry Greek, Nicoise, Gaeta, Picholine, Cerignola and Green Ripe giving Black Ripe and Spanish olives a run for their money (not to mention Stuffed Olives), some of which are dry packed in salt, some in brine and they’re all packaged according to what makes them look pretty and sell best.

This is really the only site I could find that mentions it. They are out there, check your local big supermarket, if they don’t have them check your local small specialty mom and pop italian store. I belive the ones we sell are by Roland and come in a can, but I couldn’t find them on the Roland site.

Manzanilla and Cerignola are picked when “mature” but green. I don’t know if they’d get black if you left them on the tree, but they’re not eaten then.

You may well be right. We had a potential Staff Report question on this, but I hesitated to write anything up because I couldn’t find a really authoritative statement on the subject. The information on raw vs cooked was what I was able to glean on the internet, and may not be accurate.

It may take a query to an actual olive processor to get the real Straight Dope on this.

Had the brand wrong, here’s the green ripe olives.