Vacuum Distillation in a Nutshell


What is Vacuum Distillation?

To share or not to share? That is the question. We have been called crazy by some for wanting to share our method of distillation, we wouldn’t be us if we weren’t crazy. It’s going to take a lot more than that to stop us being transparent with you.

We distil using a Buchi rotary evaporator in a method called vacuum distillation. The main reason for using this method was so that is was possible to distil one of our core ingredients: yoghurt. Yoghurt cannot be distilled using the traditional copper still method, as the temperatures are just too hot – the yoghurt would curdle and no one wants that! Vacuum distillation allows us to distil at much lower temperatures, keeping the yoghurt safe and its taste intact.

To some gin drinkers, we know that this won’t be of interest, but to the curious amongst you - here’s how it works: vacuum distillation is distillation under reduced pressure. For example, sea-level atmospheric pressure is 1000 mbar. This means that our standard boiling point of water is 100°C. If you’re on Mars, atmospheric pressure is much lower at 124 mbar, and boiling point is 10°C. The pressure we distill at reaches as low as 45 mbar, meaning that substances can be distilled at very low boiling point temperatures. The result of this is a quick and gentle evaporation process, one that doesn’t damage the taste and quality of our ingredients. Our flavours remain as intense as ever and shine through in Crazy Gin.

We vacuum distill the yoghurt, black cumin, turmeric, black pepper, pomegranate, coriander and juniper using the rotary evaporator. The gin is then fat washed with ghee, and you can read more about how this works here: link. Once this is complete, we blend them together to create our final product.  One of the most exciting things about the use of a rotary evaporator is that almost anything can be put through them. The 2015 winner of the ‘World’s Most Innovative Beverage”, Anty Gin, was created by vacuum distilling the essence of ants.

For us here at the Crazy Gin distillery, turning our hand to gin was a world away from anything we were used to. Neither of us came from a scientific background, and the equipment took a lot of practice to master! In March 2018, we were invited by Buchi to Cambridge, to demonstrate how we use the equipment to make our gin to a bunch of chemists. This was alien to them, as they had been using the same equipment in a completely different way.  However, after explaining the process and providing some delicious gin cocktails they had a better understanding of what we do.It was a great pleasure to share our story with them all!

Learning labNaomi Spence