So, you will be approaching the boiling point of ethanol and a lot of other stuff you don't want (methanol is 65c, where ethanol is 78c) will boil off along the

So, you will be approaching the boiling point of ethanol and a lot of other stuff you don't want (methanol is 65c, where ethanol is 78c) will boil off along the way, but time is a factor here, and also the fact that you are not likely maintaining a precisely even temperature along the entire column until the condensing stage, and so one will typically account for real-world pollution by discarding the first material, instead of being a cheapskate and blinding people... for example. bear in mind that there are other substances that ALSO boil around 80c-90c and that fermentation of a given substance or mixture or solution of substances will be varying byproducts (from your ethanol-questing perspective...) the sheer notion of distillation being some precise and quantized quantifiable process is likely suspect... think of cooking, and how the ingredient list is only part of how a given dish may turn out...