Capers from grapes?

I've recently read of someone fermenting elderberries to make 'capers'. Has anyone tried the same with unripe grapes? (There are loads growing wild here in rural France and I would love to know if something can be done with them).

I'm not sure about making "capers" out of those things, but a good use of unripe grapes is verjus, which can then be used in cooking, like sauces, salad dressing etc.

http://gathercatchcook.com/elderberry-capers-its-easy-and-its-right-now/  How to do the Elderberries and they warn about the acid that needs to be dealt with....

The only use I know for unripe grapes is to mash and ferment out to make verjuice, a sort of vinegar. Haven't made the stuff in years (grape allergy that showed up one day and hasn't left!)

Grapes and capers can make excellent sweet and sour sauces for things like fish.

The wildlife people tried to convince us to eat Scotch broom buds as capers. Nobody did because they taste bad.  Capers grow best in dry places. I don't live in one, so I buy them when I need them.  I make sauerkraut and it doesn't have to be a tiny bud/berry to have it's flavor.  I ferment many things that taste bad or are too fibrous until fermented, like broccoli stems, cauliflower stems, kale stems, amla,  turmeric, lower asparagus shoots, etc. Some things like broccoli, beets and cabbage are barely tolerable raw but really good fermented.
John S
PDX OR

This is so cool!  Here I am in deepest France and being given the 'recipe' for verjus!! Not only that but the giverecipe.com site by Zerrin talks of kids eating the green grapes to get the unique zap of flavour which must have brought tears to their eyes! ... I just had to do it ... and sure enough its like sucking a very, VERY unsweet lemon!! But hey I was a 50's child and we joyfully sucked onto our lead painted toys!!!

So, I have just got to make some grape capers. The verjus is already an amazing addition to the kitchen. I'll tell you how the capers go in about a weeks time.  

I don't know if anyone is following this, but here is an update.  The grapes are fermenting well, the fruit now has taken some of the sweetness from the honey, and perhaps from the cider vinegar. I think it will need a month or so for the fruits to lose the crispness. The interesting thing is that the ferment is now producing a mother of vinegar, which is great ... but does anyone have any suggestions as to what I can do with it besides making more vinegar?