Making spirits at home is not only interesting, but also a great learning experience. However, preparing any alcoholic beverage yourself requires proper care and precision.
How is Methanol Produced?
Methanol, also known as methyl alcohol or wood spirit, is the simplest of alcohols. It consists of one part carbon, one part oxygen, and four parts hydrogen.
Methanol is commonly produced commercially from coal, natural gas, and other renewable sources such as recycled carbon dioxide, biomass, and municipal waste. Previously, it was produced by distilling wood, but today it is produced from synthesis gas through catalytic reaction between hydrogen and carbon monoxide.
In addition to commercial production, methanol is also produced in small amounts during the alcohol distillation process. It is generated in the initial stages and discarded by distillers. This biodegradable form of alcohol is an organic, water-soluble chemical.
ACE copper distillery equipment
How to Minimize Methanol in Fermentation?
During the fermentation stage of alcohol production, methanol is produced.
The amount of methanol produced varies depending on factors such as temperature, the type of yeast and bacteria present, the type of food provided, and the minerals used.
Fermentation of starch-derived sugars from crops like corn, wheat, and barley generally results in very low amounts of methanol formation.
A couple of general rules to minimize methanol during distillation:
Be more cautious about methanol when distilling fruits compared to sugar or grain washes, or whiskeys.
Brandy made from distilled fermented grapes contains less methanol than schnapps (fruit brandy) made from fermented apples or citrus fruits.
Remove pectin from the food sources used or select items that do not contain pectin to prevent microorganisms from producing methanol.
Use high-quality and reliable yeast.
Control the temperature during fermentation and avoid excessive heat.
Sterilize all equipment before fermentation to eliminate harmful bacteria.
Can you Test for Methanol in Alcohol?
Yes! You can test for the presence of methanol in an alcoholic beverage through some quick tests.
The Smell Test
Smelling the beverage is the easiest way to test for methanol, although it requires practice to develop your senses. If you detect an unpleasant chemical odor, the drink is not safe to consume.
Methanol has a sharp, stinging scent that is distinct and easily recognizable as “the smell of alcohol.”
In contrast, ethanol has a milder smell. It is softer, less pungent, and has an almost “creamy” aroma. Ethanol does not have the same potency as methanol at the same concentration.
Ethanol will generally have a pleasant smell, but it is difficult to distinguish without comparing it directly to methanol.
The Flame Test
To perform the flame test, take a small sample of the alcohol solution and ignite it. If the flame appears yellow instead of blue, it indicates the presence of methanol.
Keep in mind that in practice, you rarely encounter solutions that are purely methanol or ethanol. They are usually blends with varying proportions.
Exercise extreme caution when working with fire, as distillation can be a potentially explosive process. Keep any open flames far away from the equipment.
The Chemical Test
A more effective test for methanol in alcohol involves using sodium dichromate on a small sample of the solution.
Mix 8 mL of sodium dichromate with 4 mL of sulfuric acid. Swirl the mixture and add 10 drops to a small container or test tube containing the alcohol to be tested.
Gently swirl the test tube and fan the air from the opening towards your nose while holding the tube approximately 10-12 inches away. Observe the smell – if it is unpleasant and pungent, the alcohol contains methanol. If the smell is fruity, the beverage only contains ethanol and is safe for consumption.