Separating ethanol from methanol

[Vale71]

The best information I can find (although admittedly not 100% conclusive) still says the methanol is from pectins in the ferment.

No it doesn't, at least not the information you have linked in your posts. Once again, there is zero proof of any methanol production during fermentation. Presence of methanol in the finished product alone does not prove anything other than that there is some methanol present.

 

[Gnomebrewer]

No it doesn't, at least not the information you have linked in your posts. Once again, there is zero proof of any methanol production during fermentation. Presence of methanol in the finished product alone does not prove anything other than that there is some methanol present.

But it's all circular logic anyway, because the original intention was to show that there is a trace amount of methanol in beer. I haven't seen any proof that there isn't some methanol in beer, the common wisdom is that there are trace amounts, and the onus of proof with food is to prove that the harmful chemical doesn't exist. Therefore, until I see conclusive evidence otherwise, I'll believe there is a trace amount of methanol in beer. I'll also continue to consider it highly likely that it comes from trace amounts of pectin from the grain. I've quite enjoyed reading about the subject and definitely learned more about it. I'm not suggesting the methanol is produced through the fermentation process (although I did originally think it was a byproduct in the same way as, for example, an ester, which I now know is not correct) but that it happens at the same time. That is mentioned many times in articles I've read, although it is possible that they all link back to one study.

 

[gatewood]

Just to clarify you guys, I ain't distilling beer, I used the word "homebrew" in a broader sense, not just beer... I apologize if I caused some confusion (didn't expect this would become such a heated discussion).

I have ferments (some made of plain glucose, others with fruit wort) with around 25% alcohol.

 

[Gnomebrewer]

Just to clarify you guys, I ain't distilling beer, I used the word "homebrew" in a broader sense, not just beer... I apologize if I caused some confusion (didn't expect this would become such a heated discussion).

I have ferments (some made of plain glucose, others with fruit wort) with around 25% alcohol.

Even if you could collect pure methanol, the methanol content is still very small in terms of collecting a pure sample of it (but remember it only takes a small amount to kill a person). In this study https://www.bio-conferences.org/articles/bioconf/pdf/2017/02/bioconf-oiv2017_02028.pdf, 280mg/L is listed as the upper end of the typical range for red wine. At that methanol content, 5 gallons of red wine would contain about 5.6mg, or about 7mL of methanol. Hardly worth worrying about when methanol produced from natural gas is cheap to buy.

 

[gatewood]

Even if you could collect pure methanol, the methanol content is still very small in terms of collecting a pure sample of it (but remember it only takes a small amount to kill a person). In this study https://www.bio-conferences.org/articles/bioconf/pdf/2017/02/bioconf-oiv2017_02028.pdf, 280mg/L is listed as the upper end of the typical range for red wine. At that methanol content, 5 gallons of red wine would contain about 5.6mg, or about 7mL of methanol. Hardly worth worrying about when methanol produced from natural gas is cheap to buy.

Then I guess I'll settle with just producing ethanol.

 

[Orval]

It simply isn't. Methanol is a naturally occurring constituent of pectin-rich fruits and vegetables, even of common tomatoes as you can see in this study. If fermented and possibly distilled beverages are produced from such fruits then some amount of methanol will inevitably be carried over to the beverage but that does not imply any direct link with the fermentation process.

True! There's some methanol in your favourite orange juice!
Methanol comes from the hydrolysis of pectins, nothing to do with fermentation. Depending upon your batch size, you discard the first ml. Let's take one example, - 20 litres batch low wines at 42%ABV from a stripping run; discard the first 50ml as foreshots, mainly acetone and methanol, keep the next 250ml as head and another 250ml which can or cannot be added to the final product depending upon how neutral and how "hangover free" you want it. Foreshots can go to a bottle of barbecue lighter or general purpose solvent, the heads can be added to the next spirit run.