We can make robots from gelatine and other edible ingredients

Soft, edible robots that mimic real organisms could be used to deliver drugs to animals. That is just one potential application of a new material made from biodegradable gel. "The question is, could we develop a material that is, at the same time, very reliable while you use it, but once triggered can completely degrade?" says Martin Kaltenbrunner at Johannes Kepler University Linz in Austria. Kaltenbrunner and his colleagues created a gel out of ingredients that are safe to eat, including gelatine – which can be fully degraded by the body – citric acid to stop bacterial growth and glycerol for softness and to prevent dehydration. The biogel is designed to be eaten by bacteria commonly found in waste water, meaning it will break down naturally if it ends up in landfill, for instance, but remain stable otherwise.