It’s not always possible to leave a clean plate. Chitin from crustacean shells, for example, can be used in many ways.
A girl from Malaysia is ensuring that waste from fish restaurants is meaningfully re-used. Fish waste is also an important ingredient in animal feed.
The 11-year-old collected 30 kg of shrimp and sea snail shells from seafood restaurants and turned it into feed for cows, chickens, goats, pigs and fish.
Having cleaned the shells, she left them to dry in the sun before finally grinding them into powder. After a week the first samples were tested at a local cattle farm.
The results were encouraging. The girl recently won first prize at a major US invention competition.