Experiment: Water Mineral Profile and Gin

[Warthaug]

Several years ago I posted a thread asking whether anyone had experimented with water mineral profiles in their spirits. My rational was based on my experience as a beer brewer, where high-sulfate water is used to emphasize the dryness and hop character of a beer, and where high-chloride water is used to generate mouthfeel and emphasize malt character.

I finally got around to testing this myself, using gin, because a) I love gin, and b) many of the herbal characters in gin are similar to the hop characters sulfates are used to emphasize in beers such as IPAs (e.g. citrus, pine, and resin notes).

My approach was simple, I made my standard gin using an airstill:

• 1L of 50% ABV grain spirit
• 35 g juniper berries, half lightly crushed, half whole
• 8 g mixed fresh citrus zest
• 7 g coriander, lightly crushed
• 0.7 g Angelica root

Steep at room temperature overnight, then at 50C for 1 hour before diluting to 40% ABV and distilling.

Once the raw distillate was collected, I diluted it to 42% with grocery store distilled water, split the distillate into thirds, and added:

• Nothing
• 0.35 g/L gypsum (~80 PPM calcium & ~200 PPM sulfate)
• 0.4 g/L calcium chloride (~110 PPM calcium & ~200 PPM chloride)

My wife and I then did some triangle tests, where we served each other 2 servings of one of the gins, and 1 serving of a different gin, to see if we identify the odd gin out. Each time we paired the water-diluted spirit with one of the spirits with the mineral additions.

As straight gin, all the high-gypsum was night-and-day different (we both identified the high-sulfate gin 3 in 3 tries), while the water and calcium samples were different, but not hugely so (we could tell these apart 2 of 3 (me), and 3 of 3 (wife) tries).

Chloride did not do much; the spirit felt a little "rounder" in the mouth, and some of the "sharper" edges on the pine notes were softened, relative to the pure water control. Subtle, but noticeable if you knew to look for the differences. I'm not convinced that someone would notice the differences if they weren't aware of what they were supposed to look for.

The gypsum samples were very different. The gypsum amplified the citrus notes of the coriander and zest, and brought out more of the "berry" note of the juniper. The bitterness was also more apparent, but not in an unpleasant way. In my opinion (I like intense gins), the addition of gypsum greatly improved the flavour of the gin - more intense, and more citrus. My wife was the opposite, and thought things were too intense for her tastes.

A few days (and a hangover) later we did triangle tests, using these gins in gin and tonics...and couldn't tell the difference between any of them. The dilution of the minerals into the tonic, plus the flavour of the tonic, completely removed any detectable differences between the gins.

Anyways, it was a fun little experiment that I thought people here would find interesting.

[Ridgeback816]

Very nice write up I am about to dip my toe into gin so I will definitely keep this in mind

[Yummyrum]

Nice experiment warthaug .
Sometimes you have to try things .
Thanks for sharing

[Turbo6ta]

I am down here in southern Florida and our tap water tastes really bad. Because of this I only use bottled water to make coffee (much better taste).

As far as distilling homemade gin, I wonder if this nasty tap water would effect the taste of the finished gin after distilling ... Or would the distilling process remove all the the bad taste of the tap water used ?

I am really reluctant on using our tap water to make gin at home.