Juniper! is the obvious pub quiz response. And of course, that’s correct. Juniper is definitely the main thing, but there’s plenty more you need to know about the gin making process before you can really say you know about gin. How is gin made? How long does the gin making process take? How are the different varieties affected by the locality in which it’s made? Where does gin come from? What makes top-quality gin, and is price a factor in which is the best?
There are several traditional methods for making gin. In each case, you start with a neutral ethanol spirit, to which different flavourings are added. Most commonly, the spirit goes into a pot still together with the juniper berries and a few other botanicals. A day or two of steeping creates a distinctive flavour. And then, to get the gin back down to a milder strength ready for bottling, water is added. This is the method used in, for example, Silent Pool’s English Rose Finest Dry Gin. Another, more subtle approach is to suspend the botanicals in a basket over the spirit, and heat it. The vapours mix with the botanicals and condense back into the gin for a gentler taste. Gins such as Bombay Sapphire are made this way. In the case of, say, Hendrick’s Gin, both distilling methods are used, with some botanicals placed in the spirit for steeping, while others are hung above in the basket.
While those tried and tested methods are the gin making norms, more recently gin production has diversified with ingenious new forms of flavour extraction and experimental ingredients. In this category is the vacuum distillation, which you’ll taste in Cabin Pressure or Victory Gin. The boiling point of the ethanol is lower in a vacuum, which produces a different taste from the same ingredients. In fact, if you make the vacuum even stronger, the spirit boils at an even lower temperature. It’s technical stuff, made all the trickier when you consider this often has to be made in industrial quantities.
One-shot gin making process, which is mostly used for craft gins and smaller distilleries such as Sipsmith gin, use a given amount of base alcohol which is then distilled with botanicals according to the recipe. Two shot gins are redistilled twice, with the concentrated liquid added back into the original recipe. This process doubles the volume of gin, which increases production capacity. Multi-shot production methods have the added benefit of evening out any discrepancies in flavour, so this is the most popular method for large scale gin-making internationally.
All gins are not made the same - every single brand of gin uses a particular recipe to create their unique taste, and it’s down to the distiller to ensure uniformity in the brand, even though different crops year after year will have a slightly different flavour. Even juniper berries. As you can imagine this is a skilled job that involves regular tasting and a knowledge of how different processes affect the flavour and ingredients.
Using a seasoned cask, you can age gin by storing it for a few months to mature. Or you can just open a bottle of tonic and drink it now.