Do you know your London Dry gins from your Old Toms? Here's a brief guide on the most popular styles of gin.
Although originally made in London, London Dry Gin can be made anywhere in the world. It first appeared around 1831 and superior distillation techniques meant the spirit was pure enough to be sold unsweetened (dry).
However, there are strict EU laws regulating which gins can legitimately be called London Dry. All botanicals must be present at the time of distillation, i.e. you cannot distill a gin, then add flavouring.
OLD TOM GIN
At one time this sweet (sometimes called cordial) gin was most popular in the 18th and 19th Century. This was largely due to the poor purification of the base spirit leading to rough tasting gin that needed sweetening to make it palatable. Liquorice was originally used and later sugar was the sweetener of choice.
NAVY STRENGTH GIN
Navy Strength Gin has to have an ABV of over 57% to appear in this category. Note the average ABV of gin is between 40-43% so Navy Strength gins are very strong and need to be consume in moderation!
Navy Strength gets its name from a nautical tale. The story goes that if you spill gin of 57% or over, on gunpowder, there will still be an explosion, so this was the strength that Naval Officers demanded. If the gunpowder didn't light during testing, they knew their gin had been watered down.
The historical practice of ageing gin is coming back into fashion. Gin doesn't need long ageing like whisky or brandy, with three months considered adequate time. Well-seasoned casks are used to help the ageing process.
The juniper notes round out in barrel-aged gins with honey and cinnamon notes more noticeable.
Technically speaking, sloe gin is a liqueur and is made by mascerating sloe berries in gin before adding sugar. It has a lower ABV and is a bit like a fortified wine or port.
Example: McHenry Distillery Sloe gin