In movies, generally when the “mad scientist” appears, inside his laboratory it is possible to observe various organs and creatures in a jar, with a liquid substance that is probably alcohol, something that is also often seen in some museums where they are kept for example animals or small insects. But why is this use? Why is alcohol used to preserve things?
Why is alcohol used to preserve things?
The use of alcohol as a “preservative” is not trivial. The liquid, in fact, has been used since ancient times to preserve all kinds of samples. A technique known as “fluid preservation” which, if applied correctly, allows tissues to be preserved for centuries.
To explain how the technique works or how alcohol is able to preserve things, Bill Carroll, a chemistry professor at Indiana University in Bloomington, recently explained to Live Science that “alcohol is toxic to guys. of microorganisms that would cause decomposition.
To understand it better, we can take the wine itself as an example. To make the drink, a yeast eats the sugar from the grape which, in turn, transforms it into alcohol. The yeast excretes so much alcohol that the concentration becomes toxic and dies by its own process. The alcohol content of the wine, around 14%, helps to preserve the drink even for years. In fact, we all know that the longer a wine is stored, the better it tastes.
However, the storage of other types of organic materials, such as DNA , tissues or even whole animals, requires a higher concentration of alcohol, according to the same website Katherine Maslenikov, head of fish collections at the Burke Museum in Seattle. For example, formalin (a solution of formaldehyde gas dissolved in water) is often used to stop internal biological processes.
Alcohol in even higher concentrations, for example 95% ethanol, acts as a desiccant . Which means that it removes and replaces water from the cell, tissue or sample of the entire body. This technique is a common way to preserve DNA, according to a 2013 study that was published in the journal PLOS One.
So what amount of alcohol is just and necessary depending on each sample? according to Carroll ” A concentration such that it inhibits microorganisms, but does not destroy the cellular structure of what you are looking at.”