I'm thinking of throwing away my brother's food
If someone threw away your food how would you feel?
I might feel upset by the thought that I give him food in abundance but he doesn't appreciate it.
You shouldn't throw away someone's food. If you're going to perform charity don't attach any conditions alongside it. People will feel as if they owe you something in return.
I'm not that kind of person, I'm definitely doing good here.
If you think you're not that kind of person, you won't throw away your brother's food. It's a waste of resources. You can rather give it away to someone needy.