We are going to Vietnam this year for holiday and I’ve read horror stories of poorly distilled alcohol in cocktails and such. Several tourists have died from methanol poisoning.

Would it be feasible to build a small detector for methanol? I’m okay with either a small chemical identification test or something like an IR spectrum analysis.

There are commercial test kits for professional laboratories but I need something affordable for regular consumers.

  • DerGottesknecht@feddit.org
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    2 days ago

    Yeah, ethanol doesn’t get turned into methanol by distillation. But fermentation produces both and one purpose of distillation is separating them. Thats why you have to remove the foreshot. An incompetent distiller can still cost you your eyesight or even life.

    • m0darn
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      1 day ago

      one purpose of distillation is separating them

      The purpose of distillation in this context is ethanol concentration. Methanol separation is possible but not really the goal.

      Thats why you have to remove the foreshot

      I don’t think the foreshots have a particularly higher concentration of methanol, other nasty stuff sure, but I think methanol is in pretty similar concentration to the ethanol.

      An incompetent distiller can still cost you your eyesight or even life.

      My understanding is that it’s people cutting the ethanol with industrial intoxicants that gets people injured/ killed. Ie people recklessly adulturing the alcohol.

      The only problem I’ve heard of that’s from distilling itself and not intentional contamination is people doing freeze distillation of ciders (skin on).

      That said, most of my reading has been with respect to pot stills and grain beers, maybe fermenting fruits create more methanol than grains, I still think intentional contamination with who knows what is higher on the risk list than accidentally high methanol concentrations. But if you know of specific cases I’d be happy to read them.

      • DerGottesknecht@feddit.org
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        19 hours ago

        Methanol separation is possible but not really the goal.

        If you’re producing spirits it should be your goal. Especially if there is wood in the mash.

        I don’t think the foreshots have a particularly higher concentration of methanol, other nasty stuff sure, but I think methanol is in pretty similar concentration to the ethanol.

        Thats wrong, methanol has a lower evaporation temperature than ethanol, thats why it’s in the foreshot.

        And yes, most of the time it’s greedy business men mixing industrial methanol in their drinks, but there have been some cases of poisoning with self destilled alcohol in the Balkans, i.e

        https://deutsch.radio.cz/methanolvergiftungen-der-slowakei-ursache-ist-tschechischer-schnaps-8337380

        Sorry link is in german.

        • m0darn
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          9 hours ago

          Ah my bias: I was only interested in grain mashes. My immediate reaction was, “why on earth would there be wood in your mash?” The answer is fruit stems. Methanol will be differentially in the foreshot but if you’re not expecting much because you’re not fermenting any wood, it’s going to be low in the foreshots and very low in the hearts, but not much anywhere. BUT if you’re fermenting something with woody stems, I can see that methanol removal is going to be worthy of consideration.

          • DerGottesknecht@feddit.org
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            2 hours ago

            Not only stems, but if you just rake up your fruits and put them in a mash you get all kinds of sticks and leaves also in there. If you ever make a schnaps take care with the foreshot :)