Will I go Blind ?

A big fear for many new distillers is that they are risking poisoning themselves with methanol - a toxin that can cause blindness. There is little basis for this fear however; if formed, it is only in small amounts, and can be easily discarded with the "heads" collected first (see here) during distillation.

A simple (but effective) rule of thumb for this is to throw away the first 50 mL you collect (per 20 L mash used) for a reflux still. If using a potstill, make it more like 100-200 mL. Do this, and you have removed all the hazardous foreshots, including the methanol. To get a really clean distinction between the foreshots and the rest of the alcohol, increase the reflux ratio to the point where you're taking off this first 50 mL at a very slow rate (eg 1 drop per second). This will give a very stable equilibrium within the column to allow all the methanol to collect at the top of the column and be in this first portion.

If you are doing a double or triple distillation with a pot still, don't worry about removing the heads & tails on the first pass. Wait for the second run, when they are more distinct & easier to seperate. Once you have removed them, they are gone, so much less will need to be discarded from the subsequent runs, other than that dictated by taste, and any improved seperation that may result from running a more pure distillate through the still.

How dangerous are the various fusel oils ? I've got some of them listed below.
The ones with toxicity data listed are ...
  • Methanol : usual fatal dose 100-250 mL
  • 1-Pentanol : LD50 (rat) 3030 mg/kg
  • 3-Pentanol : LD50 (rat) 1870 mg/kg
Compare this to the amounts present in distilled spirits. The data in Wheeler & Willmotts "Spirits unlimited - a complete guide to home distilling" gives :
  • Home distilled spirit (untreated): methanol 0.0067%, ethanol 99.632%, fusils 0.361%
  • Commercial vodka: methanol 0.013%, ethanol 99.507%, fusils 0.48%
  • Poor quality home distilled spirit : methanol 0.0186%, ethanol 98.453%, and fusils 1.528%
If you're talking about untreated spirits as being dangerous, then to reach the LD50's that are published, you'd need to consume 149 L to be affected by the methanol, or for a 90kg bloke, about 58 L for the pentanol, from the "good" homemade stuff. That would be one hell of a session ! Even on their "poor quality" brew you'd need 11 L for the fusels. Stock standard pissed-as-a-newt high-school-student alcohol poisoning is the greater problem.

Now their "home distilled spirit" was at a time when their best design was only putting out roughly 75% pure ethanol. What's the story from like a Nixon-Stone or Euro doing 95%+ purity ?

Compare that to the levels of methanol etc that you get via other sources ...

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