These parts: peels, ends, seeds etc that other people throw out and become parts of meals where other people would have to go out and buy something.
Examples are carrot top pesto (doesn't smell great but tastes delicious), Veg scrap stock (also not a great smell when you are making it-but great in everything you would usually add stock to) apple scrap vinegar (which I don´t actually use in food, but do for cleaning).