Maybe it's because of my bad teeth, but when I eat chocolate covered raisins, I end up with very little chocolate as I finish the raisin. Even though the raisin tastes good, I'd rather have more chocolate taste at the same time.
So then I had a thought of chocolate in the middle instead of the outside.
I first thought of the insert a solid piece method, then later the insert mix method.
My thoughts jump right to making machinery for a factory. But maybe this part can also describe a home hand tool, used with physically holding the grape or some kind of simple holder to place one at a time in.
But the factory version sorts and loads grapes into feeders that put one grape at a time into a holder, that maybe closes while inserting to insure the grape doesn't burst, quick insertion in one end with a needle, and then eject the grape out the other side.
The needle for the solid piece is like a tray with a back end that the piece of elongated chocolate rests against. It comes to a sharp point at the other end that inserts into the grape. If necessary the back end rest piece can be used to hold the piece in position while the tray retracts first.
So then the idea migrated to what if a needle goes inside and inserts a line of a mix as it retracts. A mix of cacao, sugar, and milk powder.
Then during the dehydration process, a lot of the juice will mix and make the chocolate.
I first thought of a liquid slurry, and if the powder doesn't work, that would then be a possibility.
Heard that somewhere. And the seeds I think is guaranteed not to be in seedless grapes, but sometimes smaller ones. If possible, maybe get rid of those, but mostly don't seem to be a problem. If it's possible a normal hard seed can occur in seedless grapes, then the machinery needs to be adjusted for that.
But the stems are irritating. To me it would be worth paying workers to carefully inspect and remove all stems. And computers can also scan for them. Or maybe really advanced washing techniques, or systems where the grapes are loaded to remove at the same time.