|MadSci Network: Chemistry|
Many foods are flammable. Many substances derived from foods are flammable, like olive oil. Though trying to burn an olive might be difficult, lighting a peanut on fire is rather easy due to the oil content of the peanut. I'm talking food here because you said the instructor ate the candle. So I can't say exactly what it was made of, only give you a hint as to what type of food. It would have to be a food with a high oil/fat content, high enough to burn on its own.
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