I tried a weird experiment this week. How exactly do oils affect the taste of baked goods? I made three batches of brownies, all exactly the same, minus the type of oil in each. The first batch contained vegetable oil, the second contained canola oil, and the third contained olive oil. I found some interesting results. Most people actually liked canola oil brownies the most, which I found very surprising considering most recipes call for vegetable oil. The canola oil batch came out much sweeter. This is likely due to the fact that vegetable oil is quite bitter. The olive oil brownies came out pretty bad, as expected. What was interesting, though, was how they tasted almost entirely normal at first. The aftertaste was what got everyone. Lastly, the canola oil batch actually cooked faster for some odd reason. I might look further into this at some point. tl;dr: canola oil makes baked goods sweeter and cook faster, most preferred canola oil, and don't ever use olive oil to bake.