What causes fishy-tasting fried foods?
I know that for some people (including me), canola oil does. I guess it's genetic, like the ability to smell cyanide or taste those bitter paper strips. I've had some truly awful french fries, for example.
When I've had some subtly fish flavored bacon or eggs at a restaurant, the waitress and/or the cook usually deny they're using canola oil. Are they mistaken, or is there some other reason for the off flavor?
The problem is likely that the restos are using the same oil and/or surfaces to cook fish as they are everything else. And they're likely not changing the cooking oil frequently enough. For me, it is usually the overwhelming stink of fried chicken that puts me off my dinner. I've had to clean a lot of deep-fryers in my time, and trust me, it's not the oil. Canola should have very little smell or taste, at least until a thousand chicken wings (or fish 'n chips) have been cooked in it. And BTW, almost all restos use canola oil now that trans fats are bad.
The fishy taste is a side effect of heat, not use. Most people can't taste it, otherwise I'm certain no restaurant would use canola oil in high temperature applications.
While I saw the restaurant serving fish, they were deep-fried grouper sticks, which are not cooked on a grill like the eggs and bacon I ordered. That's why I don't think it's a cross-contamination issue.
I think it may be a genetic thing. Canola also tastes fishy to me and Cilantro tastes like dishwashing soap.
I think that some oils, when heated past their optimal temperature, can give off a fishy aroma and impart a fishy taste. Maybe these restaurants are cooking at too high a temperature.
From a site called springerlink
"The flavor quality of french-fried potatoes was significantly (P<0.05) better for potatoes fried in modified oils than those fried in standard oils. The potatoes fried in standard canola oil were described by the sensory panel as fishy".
I think a lot of deep fryers are a bit more mixed-use than they ought to be, but to me canola = fish. I recently switched over to grapeseed oil for my regular neutral oil and I'm amazed at the difference.