Gin is one of our favourite spirits, which explains why we have dedicated a club to it. With so many possibilities, and so many fabulous producers, what is not to love?! But what is gin exactly?
The words you will always hear around gin (and vodka) is that it is a ‘neutral spirit’. An accurate name but not one sparks the imagination. It sounds more like an indie band we would listen to in school while doodling love hearts all over our notebooks.
Neutral spirits offer neutral flavour, and a jumping off point for gin distillers. For the most part you will hear that gin is created from a neutral spirit derived from neutral grains (barley, wheat, corn, rye etc.). These days though we are seeing more gins that are deriving from other agricultural sources such as grapes and molasses.
Now to derive alcohol from the sugar source fermentation (the source of much of our happiness) must occur. Fermentation is the conversion of sugars to CO2 and alcohol (ethanol). When using grains, they must undergo an enzymatic conversion of their starches to sugars, when using strict sugar sources, this enzymatic conversion is not necessary. The yeasts finish up their work on those sugars, the solids are separated from the, now, alcoholic liquid called the ‘wash’.
The wash comes in at a surprisingly ‘low’ 7-15% ABV and so must be distilled to get it up to the necessary 95% ABV? In these circumstances distilling is the act of separating the water from the ethanol via their differing boiling temperatures. Ethanol boils at 78.37°C, a lower temperature than water at 100°C. The ethanol vapor is captured and cooled and converted back to liquid form. The distillation takes place in 4 stages; The first is the ‘foreshot’ and is not collected, the second is the ‘head’, the third is the ‘heart’ (often the prime part of the distillation), and lastly comes the ‘tail’. The vapours are captured at these various stages and cooled back to liquid form. Interesting tid bit: For neutral spirits the head and tails are often used to create cleaning products. Some water will vapourize along with the ethanol, so in order to keep reducing the water content, distillation is repeated until that 95% ABV is achieved.
This process is often done by an outside company and purchased by gin distilleries, as the additional costs and infrastructure make it difficult to do on site.
So now your favourite gin distillery has its neutral spirit and its time to turn it into your favourite gin! That high ABV must be diluted to appropriate gin consumer levels of roughly 30% - 60%. Depending on the distillery’s process, they may dilute before or after re-distillation.
And what you may ask is re-distilleration, well its where the fun comes in! What makes gin, gin, are the botanicals! Traditionally Juniper heavy, to this day it is the key botanical that contributes that gin-like flavour, but distillers worldwide are expanding the options of what makes up their gin’s profile. The main two methods of botanical infusion, often used in tandem, are the ‘steep & boil’; Within a pot still, botanicals are steeped in the neutral spirit for up to 48 hours, then the liquid is distilled in the same fashion as above, and ‘vapour infusion’; the botanicals are placed in a basket above the neutral spirit in the still and the vapours infuse with the botanicals as they pass through them during distillation. Vapour infusion often results in subtler botanical characteristics.
This is a small overview of what goes into gin distillation, and a good starting point for plenty more Schmooze Letters to go into the gin-making process further and flush out the great wide world of these botanical beauties.