How to deal with such nasty people ?

'racist' is a term that gives humans a bad name. Everyone lives by stereotypes, umptions and such like that. When you base a stereotype in any form it always involves race. It is what our eyes see. Nobody is racist, we are all just humans. Maybe he ate meat, it is possible. Some humans are compulsive liars, they say things to get attention or simply because they are bored. Cats meow for no reason, humans speak with the same motivation. There are several paths, tolerance, kindness, ignorance, or confrontation. You can continue to tolerate his behavior and do nothing in course. You can be extra nice to him. You can ignore him completely. Or you can be a man and tell him to shut up. Good luck.