What is gin? A rookies guide to the juniper stuff

Juniper berries.

What is gin? There’s never been more gin available in Australia than there is today, and it is very much in vogue with punters. Below, we’ve got a quickstart guide just what is gin all about.

Gin is the descendant of the Dutch spirit genever, however whereas gin is made with highly refined neutral spirit, genever is made from a distillate comprised of corn, rye, malted barley and distilled to a much lower ABV percentage, resulting in more congeners (we’ll get to genever another time).

We’ll talk chiefly about the London dry style of gin here.

Gin is made by flavouring high proof neutral spirit (around 96 per cent ABV) with a range of botanicals, chief among them being juniper.

There are a couple of ways of extracting the flavours and aromas of the botanicals.

  • Maceration: by steeping the botanicals in the spirit before distilling, some of the aroma compounds and essential oils are extracted (longer maceration produces a more full-flavoured spirit). This is best for hard botanicals (like orris root and Angelica).
  • Vapour infusion: this involves placing botanicals in a basket at the top of the still so that that as the vapours boil off the spirit they pass through the botanicals releasing their oils and aromas, before being condensed later in the process. This is suitable for more delicate botanicals like lavender.
  • Botanicals
    As noted the chief botanical in gin is juniper. This is traditionally supplemented by coriander seed, orris root, angelica and citrus peel. In many new western style gins, the cast of botanicals has grown widely.

    Juniper berries are not true berries; they are cones (like the cones of its distant relative, pine) that are slightly modified to be fleshier, resembling a berry. Juniperus is a plant native to the northern hemisphere and grows year round. Picking juniper berries can be difficult – the bushes (sometimes tall trees) have sharp needle-like leaves to protect the berries. The berries have their optimum flavour after three years, when their colour has turned from green to blue to a dark purple. They have a piney, woody and fresh aroma and this is what we associate with traditional gin.

    But gin is not just about the junipers: gin is a carefully crafted landscape of botanicals, with some brands blending ten or more botanicals. Genever uses a range of botanicals too, but its base spirit’s aroma is more apparent; its juniper more subtle. Whereas genever’s aroma is raw and unrefined – it gets you by the collar and smacks you across the face – gin is like the work of an accomplished perfumier. Genever is like clay earthenware; gin is like fine china. And there is a reason why the botanicals used in gin get along so well, though it would not have been understood so well by early distillers: they all share similar or complimentary aroma compound molecules.

    The smell of juniper – that is of most fruits, herbs, and spices – isn’t just one note, but instead is made up of a combination of aroma compounds. This means that the characteristic smell of juniper isn’t just piney, but woody and fresh-citrusy as well, all combined into a smell we identify with juniper berries. What you are smelling is actually pinene (pine), myrcene (woody), and sabinene (woody) amongst other things.

    The botanicals commonly distilled with juniper to make gin often have aroma compounds that compliment these. Thus the lemony, floral smell of coriander seed is in part thanks to pinene, citral (lemony) and linalool (flowery) but the pinene note no doubt compliments the piney notes of juniper. The lemony note in coriander seed is reinforced by a piney, citrusy note in fennel seeds (thanks again to pinene, and limonene molecules), which is also present in angelica root.

    London dry gin: only 0.1g of sugar per litre is allowed, no artificial colourings or flavours are permitted and it must be distilled to greater than 70 per cent ABV.

    Old Tom gin: sweeter than London dry gin, though there are no legal rules on what can and can’t be labelled as an Old Tom gin. This sweeter style was popular before Prohibition and would have been found in the Martinez back in Jerry Thomas’ day.

    New Western gin: Anything goes, really. Often the cast of botanicals leads to a more citrusy or floral gin, with juniper less in the foreground.

    Plymouth gin: essentially the same as London dry gin (Plymouth Gin is the only example currently being produced) except that it can only be distilled in Plymouth, England.

    How to serve it
    The classic serve is in a Gin and Tonic. Use plenty of gin, and don’t drown it in tonic. You want to taste the juniper: a good rule of thumb is 1 part gin to 3-4 parts tonic.

    Gin forms the basis for a number of classic cocktails — take a look at some winning gin recipes here.