Cotswolds started making gin on a small 50 litre Holstein still they named Lorelai before progressing to Dolly, a larger version of the same still. Lorelai is now only used for small and experiment runs.
Cotswolds use a traditional one-shot steep-and-boil distillation with all the botanicals placed in the kettle. The core three botanicals (juniper, coriander and angelica root) are also the hardest, so these are steeped overnight in wheat neutral spirit diluted with water to 60% alc./vol. to allow them to soak, soften and start releasing compounds.
In the morning the lighter botanicals, lavender, bay leaf, cardamom, black pepper, grapefruit and lime, are added. Fresh peel from the two citrus fruits is hand-peeled at the distillery. The valve which allows steam to start heating the still is opened about 45 minutes after the last of the botanicals are added.
Only a small head cut (about 3.5 litres) is taken to retain the citrus and juniper notes that emerge early in the run. The still is run slowly, yielding about 55 litres an hour over the seven-and-a-half-hour distillation. Nick Franchino, Cotswolds' head distiller, says "it's a gentle meander down and at 80%, which is quite high for gin, we cut to heads. It's clean crisp flavours we want, and this early cut captures the essence of what we're after."
Two batches of gin distillate are held together in one IBC (intermediate bulk container) for five to seven days just to allow them to mellow prior to bottling on site.
The gin has a high botanical load and so also a high flavoursome oil content. Nick told us, "we certainly wouldn't want to chill-filter because, certainly to my mind, the whole point of gin is taking what's essentially a flavourless liquid and flavouring it with botanicals. Why would you take them out again? By not chill-filtering, we retain a lot of the oils." Hence, Cotswolds Gin is bottled at 46% alc./vol., high enough to ensure those oils stay in suspension and the spirit in the bottle is clear. However, when you dilute and/or chill the gin, when making a G&T for example, those flavoursome oils drop out of solution and reveal themselves, creating a pearlescent effect. Both attractive to look at and very flavoursome.
Commenting on their tradition one-shot gin distillation process, Nick says, "We prefer distilling with all the botanicals in the kettle at the same time. Primarily because they're going to come together as they distil in a way that they wouldn't if you distilled the botanicals separately and then blend together. That approach could aid consistency if you have troubles with supply and so on, but you're not going to get a harmonious gin in the way that you would by putting them all in together. I liken it to soup. You don't make a soup from blending different elements, you make a soup by putting it all in the pot and they could come together in a delicious dish.