having those long chain hydrocarbons passing through your engine cannot be a good thing.
I was under the impression that those long chain hydrocarbons are the fuel,
Yar, indeed they are, be that fatty acids, FAME, monoglycerides... I think JV3 means the Glycerol molecule ripped from the middle of the triglyceride. Don't want that in the fuel, that's for sure

But as said above water washing takes care of it because it's soluble in water whereas FAME is not.
At least the 50:50 water test will still show it so there is an indication of quality even with fuel that is just gravity settled.