Question

Oil evaporates. We know this, it's called the smoke point. So why is it then, that whenever I try to find reference values for the latent heat of vaporisation for cooking oil, such as canola oil or olive oil, that the value is undefined in these tables? Is it unknown? Or is the purity of cooking oil so variable that no scientist dares publish even an average amount of kJ/kg required to change oil from liquid to gas? Why is this information unavailable? Follow‑up question: Is the information actually available and I've been unable to find it?

Answer 1

The lack of specific latent heat of vaporization values for cooking oils like canola or olive oil is likely due to the variability of their fatty acids composition, making it hard to define an average value that would be widely accurate.

Step-by-step explanation:

The absence of values for the latent heat of vaporization for cooking oils such as canola oil or olive oil in scientific tables is likely due to variations in their compositions and the complex mixtures of different fatty acids they contain. Each type of oil is a mix of different triglycerides which can result in variable evaporation rates and energy requirements to change from liquid to gas.

The term smoke point commonly mentioned in cooking refers to the temperature at which an oil begins to smoke and break down, not necessarily the point where it evaporates. Furthermore, the boiling point of cooking oil is typically much higher than water and occurs at temperatures that are seldom reached during regular cooking, making it relatively less important for everyday culinary applications.