In our Gin Master classes, there are always plenty of questions about Gin distillation parameters. My Microbiology Prof from Heriot Watt University and one of her pH.D. candidates just released a paper that confirms a lot of my practical hands-on observations across the 100+ Gin creations I have done either myself or in a Gin Master class.

I will skip the heavy academic content and summarize the findings in a simple way:

The more Juniper you add to your recipe formulation, the more intense the Juniper notes will be in the final Gin. This was confirmed in their study using sensory panels of 20 persons. For my small scale 3-Liter recipes I usually add 60 grams per liter of 96% ethanol. I have in past added more and yes, I get a more intense Gin.

Doing the distillation run low and slow will extract more Juniper notes into the final Gin. This seems intuitive, but now there is scientific data to support the matter. Making Gin is not a race. Take it easy, and slow down. A slower run will give the ethanol more time to extract the oils from the Juniper.

Diluting the ethanol charge in your still to 45% will give more Juniper note extraction ( versus a 60% abv dilution). I have always viewed this as intuitive. A more dilute charge in the still takes longer to heat up. Remember q=(m)(Cp)(deltaT). All that extra water in the still takes energy and time to heat to the point where the ethanol vaporizes. But, now this study proves out this notion. In the Gin Master classes I typically dilute the ethanol to 50%, but I may start using 45% to see what happens. For a home connoisseur in possession of a small copper A’Lambic still, store-bought Vodka at 40% would even suffice just fine in the still.

This is the kind of academic research that I really appreciate because it ties so forcefully to the practical realities of distilling. I look forward to hopefully seeing more content of this nature from Heriot Watt…