Painting with chocolate? Sounds not surprising. For people familiar with tempering technique, a paint brush, finger, cotton or whatever medium suitable could be coated with chocolate and painted to other food of choice. Bread, cakes, candies and the likes.
What if we are referring to real paintings. The one which is hung on wall as decorations. Obviously, chocolate is not suitable for the purpose. The work of art will undergo spoilage process after few days to few weeks. Milk is known for its poor shelf life. Sugar will attract ants. The painting is ruined whichever comes first. There is no hope for this concept. The idea suits well for short term food art exhibition though.
What if we use pure cacao. No milk, sugar and whatsoever.
Cacao has cocoa solids and butter as main components. Plus minimal water and other nutrients. Base on scientific facts and my own observation, cocoa mass blooms. They are ugly white spots due to separation of butter from solids. The problem is temporarily remedied with tempering.
When I said temporary, heat above its melting point will ruin it, resulting to smudges and bloom after. Mold growth is also a problem. Chance is very high when exposed to open air.
What if the butter is extracted, leaving only solids and some nutrients behind?
We are now talking of cocoa powder here. In industrial scale, the process is usually alkalized to maximized butter extraction output.
Well, I think it is now possible after seeing this painting and watching a youtube video about painting with cocoa powder. I never knew it is a painting fyi. I discovered its true nature recently.
How long will it last?
Not sure! However, the painting I saw few years ago has been there for years. I do not know how it look like from the day it was made. More vibrant maybe and got faded after. Or it is the original color. It has never changed a bit from the very first day I saw it.