Goku and food, OTP!
There is a can of peaches in Jeep's trunk. It's a little dented, but not bloated like Hakkai said would happen if the insides were bad, and the date printed on it hasn't passed yet, but he'd thrown it at the head of a youkai who was coming up behind Sanzo unnoticed, and knocked the guy clean out. Sanzo's expression, when he heard the 'thunk' and turned around, had been priceless.
Sanzo's ice-cream. Not after he has put his usual mayonnaise in it. Eeeew. Any food Sanzo got his hands on first, in fact. He put mayonnaise in everything.
Gojyo dared him to eat the meat bun with the mold growing on it they found under Jeep's front seat, but Hakkai told him that if he did, he would get food poisoning and be unable to eat anything when they stopped for lunch later.
He didn't tell Hakkai he had eaten a red-bean bun the previous week with just a little less mold and hadn't had any trouble, but he didn't want to take the risk that Hakkai was right anyway.
That tonic soup Hakkai had tried to give him once, when he was sick. He didn't care if that thing he saw Hakkai put in was really a fungus, it looked like a caterpiller, and it was bitter.
(later, Hakkai admitted it wasn't just a fungus, there was a bit of caterpiller in it too.)
The various youkai they met sometimes spoke of eating Sanzo. He couldn't imagine why. Sanzo looked like he would be kind of stringy and stick in the teeth, and he always smelled of gun oil and sweat and stuff, which was not necessarily a bad smell, but it wasn't a tasty smell, you know?