A visit to gin lane

Yesterday had a rare departure from Beer Street and Visited Gin Lane. Sipsmith gin mind, so posh stuff, though it must be said it didn't look posh from the outside.

There's plenty of gleaming copper inside though. Copper is important in distillation as it removes sulphur character.

Gin distillers generally buy in alcohol at 96% ABV and re-distil it with botanicals give it flavour. Which has always sounded like cheating to me but it was interesting to hear that the base spirit does give some character to the gin. A Sipsmith they use a wheat based spirit which gives some vanilla flavour, grape bases ones are more fruity and molasses give spice.

The base spirit is diluted to 40-60% ABV before distillation with the botanicals. Sipsmith are at the high end starting the distillation at 60% ABV.

The rectifier for the vodka they make

They use ten botanicals. Juniper legally has to be the predominant flavour in gin and it also adds pine and resin notes. Coriander is the next most important and gives citrus, lemon/lemon grass flavour to the gin and Angelica root is the third most important giving a dry floral flavour like parma violets without the sugar. Orris root is said to act as a fixative for flavours and is high in polyphenols. Liquorice adds sweetness and cassia gives aniseed. Cinnamon comes over quite subtlety after distillation, almond adds mouthfeel and lemon peel is, well, lemon.

Almond not on display in case anyone is allergic to nuts

They boil at 80°C and the vapour passes through narrow pipes in the neck of the still into the helmet at the top where it expands which promotes reflux.

The light vapour that escapes the still goes over the swan neck and is condensed. Despite starting with a 96% pure spirit base the heads are still high in methanol and acetone so are no used. The heart is used for the gin and will come off the still over five hours. The tails have poor character and are not used either. They are high in isopropanol but most of the poor character is due to vegetable (parsnip) character and fatty acids from the botanicals. 

At Sipsmith the heads are approximately 5% of the distillation, heart 80% and tails 15%. Some distilleries will re-distil the first part of the tails but they send all the heads and tails away. The cuts can be decided on ABV (heart 80-70% ABV), volume, flavour (nose), bubble size in still (it changes during the distillation) and temperature of vapour (83-87°C). 

They cut the heart with de-mineralised water to 41.6% ABV to make their "one shot" London dry gin.  

There are also concentrated gins made with 20-30 times as much botanicals which will be cut with alcohol and water to make the gin, distilled gins where some of the botanicals are distilled separately and compounded gins where the base spirit is simply flavoured without distillation.

We had a taste to three different cuts from the heart of the distillation and they were noticeably different. Hydrophobic compounds will to some extent go over the still earlier than their boiling point would suggest, sweetness and glycerine come over more in the third hour.

If peppercorns are used as a botanical the flavour comes over really late so  they don't work well with fruit which comes over early.  

It was an interesting visit, and the first time I've drunk gin in a long while.

It still tastes better with tonic in it though.