It's not perfect, but there are cleaners with enzymes that really fight dairy spill smell. They're primarily marketed here as pet odor destroyers. A spilled spring latte came back to haunt my car carpet in the summer despite my best cleaning efforts initially. I sprayed with the enzymatic cleaner and cut it in half within a few days. I sprayed again a week later and got rid of most of it. If it sits for a few days in the heat, I could smell it upon entering, but it easily got evacuated with open windows for a minute. Like 4 years later it's still there very faintly, but now it has to sit for like a week in the summer and it's only identifiable because I know what it is.