I'm going to negatively react to how my roommate handles food
Why? What's the problem with your roommate handling food?
He is enjoying the food very much (slowly) and it's annoying
You shouldn't make fun of your roommate's food habits. That's really rude. You should be more respectful.
What's the point? He's weird, he eats slowly and speaks weirdly.
He's not harming you in the process and you can just ignore him while eating so that him eating slowly won't be such a big deal. He may have a condition and it is not appropriate or funny for you to mock how he eats and how he talks. I hope you apologize to him and see how you can help him eat or talk better, if you're really bothered by it.