WHISKY gets a lot of publicity and appreciation in Scotland, but very few people appreciate the science behind their dram, and the stellar biology, chemistry and physics involved.

Just three ingredients – water, barley and yeast – go through a process of malting, mashing and fermenting, before ending up in a copper still.

All whisky stills look more or less the same, with a rounded bowl-shaped bottom and a long neck at the top. As the spirit is heated in these stills the lighter alcohol vapours rise up the neck, before cooling, condensing and running out as a clear liquid.

Once distilled, the spirit must be aged in oak barrels for at least three years and a day before it can be called Scotch whisky. During this process, flavours from the spirit combine with flavours from the wood, and chemistry gets to work.

Two of the major flavour compounds imparted through the ageing process are lactones and aldehydes. One of the most obvious flavours in whisky comes from the aldehyde called vanillin, which is what gives bourbon an especially vanilla-y flavour.

As well as chemistry, whisky involves physics. When you swirl your whisky around your glass, some places have a slightly lower concentration of whisky than others. These places have a higher surface tension and pull liquid from the surrounding areas into these straight “legs”.

Having sampled the whisky and appreciated the chemistry and physics behind the spirit, you may become intoxicated: you are literally ingesting a toxin. Your liver attempts to clean this toxin out of your body, but sometimes it can’t keep up, and you start to get drunk.

Your brain will release a hormone called dopamine, the brain’s reward molecule. You will feel euphoric, and your inhibitions will lower. Given time, the alcohol will enhance the effects of a neurotransmitter called Gamma-Aminobutyric Acid (GABA), which will make your movements sluggish and your speech slurred.

And finally, we’ll return to the beginning, before glasses and even before distillation. To make whisky, you have to start with the Big Bang. (To be fair, that’s true of anything, but for now we’ll keep the focus on our dram.) The Big Bang happened 13.8 billion years ago, and made all of space, time and the stuff that fills it. This is, of course, a very abbreviated summary. Once the universe had expanded and cooled a little, the elements hydrogen and helium formed.

Over millions of years, clouds of hydrogen and helium collapsed under their own gravity and became dense, hot and bright, forming stars. These stars fused hydrogen together to make more helium, and then fused helium together to make heavier elements such as carbon and oxygen, and so on into heavier elements, until the stars exploded, scattering this matter out into the void.

Over time, new stars – and planets – formed out of this stellar debris. Everything around you – the silicon in your whisky glass, the elements that make the flavour compounds in your whisky, the oxygen in the air – came from inside an ancient star.

Everything that is, except the hydrogen in the H2O, which came from the Big Bang itself.

The entire 13.8 billion years of history have all led to the whisky in your glass. Slainte!

Glasgow Science Centre’s The Science Of Whisky is on January 31, and tickets are available online at www.glasgowsciencecentre.org