Without using any special vacuums or clean rooms, graphene can be patterned into an impossibly thin, edible circuit–including fuel cells to store power, radio hardware to transmit data, glowing elements to light up, and even all sorts of sensors, too. These circuits resemble a dark, inky tattoo, a bit like much burnt toast.
Researchers at the Rice University have successfully used a commercial laser to transform the surface carbon in foods–like toast, coconuts shells, potatoes, and Girl Scout cookies–into graphene. They opine that in the not so distant future, all food will have a tiny RFID tag that gives you information about where it’s been, how long it’s been stored, its country and city of origin, and the path it took to get to your table. The technique though, only seems to work on foods high in lignin, the rigid plant polymer found in woody items like cork.