Black or Black? How to Tell If Your Olives Are Really Black?

Perhaps you have ever seen perfectly black olives floating in a chemical solution, and you may have been suspected that they are fake, dyed black olives. And most likely you are right. 

Also, perhaps you know, that black and green olives are not different olive varieties. Black olives grow on the same tree as green olives, and not only on the same tree but even on the same branch. It is the producer who decides whether they should be black or green, simply by determining the time of harvest. 

If the olives are harvested in September or October, they are green: 

If the farmer decides to wait a few months, the olives will be black: 

What? Are these olives not black enough for you?

That's right, it's just because these are real, naturally ripe black olives. They will not become blacker, at least while they are on a tree.

Let's go back to the can of black olives we saw in the supermarket. What are they?

These are green olives harvested from a tree in October and dyed with iron gluconate, ferrous gluconate, or ferrous sulfate. 

Meet our hero: Iron Gluconate C12H24FeO14. 

By the way, it's time to answer the question of the title: How to make sure your olives are really black?
Just look at the pit. Under normal conditions, olive pits never turn black. So if the pit is black, then your olives are colored. 

Why do they dye olives? It's simple, just two things: 
1. Money today is better than money tomorrow. It’s better to sell olives right now than in two months. Every day of growing olives is a cost. Therefore, it is better to stop spending money as early as possible, especially if these expenses do not increase profits.
2. Let’s say you have 100 kg of green olives on your tree in October. Do you think you will have 100 kg of black olives in December? Of course, you will not. Some olives will rot on a tree, some on the ground, and some will be spoiled by olive flies. Leaving them to ripen on the tree, you risk losing up to half of your yield. 

Therefore, some olive producers simply harvest the entire crop in October and divide it into two parts: green olives and green olives that turn black once they're jarred.

You don't need to do anything with green olives, they are already green. As for the second part of the olives (which are still green), just add some iron gluconate and they will become perfectly black and very shiny, like the patent leather shoes of 1930s Chicago gangsters.   

This kind man loved this product so much that he invested billions in it. And now we all believe that he lives so happily ever after solely due to the daily intake of 5 cans of this wonderful drink.