Is a black olive only a green olive that later turns to a black olive?

Question

Is a black olive only a green olive that later turns to a black olive?

Answer 1

From this University site:

http://www.botgard.ucla.edu/html/botanyt...

I found this:

"Raw olives cannot be eaten because they contain the bitter glucoside oleuropein, which must be neutralized. Unripened olives are processed in several ways. The simplest method, still used in home curing, is to salt them or soak (submerge) in a strong salt solution (one cup of salt per quart of water), and twice a day throw out the bitter fluid. Commercial production of green Spanish olives involves soaking in lye (sodium hydroxide), then 6 to 12 months in a weak salt solution (brine) to promote lactic fermentation. Soaking in brine also tenderizes the parenchymatous mesocarp. Black olives, such as the wonderful pitted Kalamata olives in Greek salads, are produced from lye curing and oxygenation. Afterwards, fruits are stored in dilute brine, olive oil, or vinegar, and sterilized before packing. The "stone," i.e., the endocarp, may be removed, and the olives can also be stuffed with pimento (Capsicum)."

Another web site ( http://www.crfg.org/pubs/ff/olive.html ) concurs that the color difference is the result of differential preparation:

"For California canned commercial olives, black olives are identical to green olives. The black color is obtained by exposure to air after lye extraction and has nothing to do with ripeness."