Capsaicin is the chemical responsible for the burning sensation in chilli’s or chili based food like curry.
Capsaicin is an oil and is completely insoluble in water, which is why you need a fat containing substance such as milk to remove the burning sensation.
Capsaicin is also very soluble in alcohol, which is why beer and curry are such a good match.
Wasabi (and other mustard’s), on the other hand, comes from allyl isothiocynate which is more volatile as well as being soluble in water. This is why you get a fast and more intense short lived hit from wasabi.
Being extra vollatile it also evaporates much faster which is why you often feel it in your nasal passage and get watery eyes.
Nugget of Knowledge 