The historic gin in question is the Hiram Walker 5 O’Clock bottled in the 1940’s (so 70+ years old). This was the Tanqueray Ten of its day and was produced by Herman Willkie and Paul Kolachov who were two of the most significant distillers ever. Arroyo even thanks Kolachov in Studies on Rum. A few years prior to this bottle in 1937, Willkie and Kolachov write Controlling Gin Flavor in Industrial and Engineering Chemistry. I also have, but have not shared, all their lost protocols for analyzing botanicals to scale botanical charges.
The last gin I wrote up as a birectifer case study was the gold standard, Tanqueray. The biggest value proposition of the birectifier may actually be gin.
Sadly, I botched this one to a small degree (and I’m actually going to do it over). My error was that I did not measure the alcohol correctly, over estimating it, and not scaling my charge to 100 ml of absolute alcohol. The result is that some of what should be fraction 5 spills over into fraction 4. This error reveals part of what is so special about the birectifier and its techniques. The birectifier distills at very near the azeotrope in the first four fractions then drops off like a rock. With 100 of absolute alcohol, the drop off gets pushed over until it is firmly in fraction 5 which is where a ton of important aroma compounds fall, be they gin, rum or whatever. Collected correctly, the fractions are well delineated and rapidly inform actionable decisions. I recently explained more of the concept here.
[What I think needs done in such situations, where the ABV cannot definitely be known is err on the side of too much and possible shoot for 105 ml of alleged absolute alcohol (instead of only 100). The idea here is to create a better chance of delineation between fraction 4 and 5. There is a much clearer strategy in aromatized spirits where you can expect no fusel oil. If your overcompensation puts you at a true 100ml, perfect, if is accurately 105, then you’re still delineated which is important because this is a zone for high impact aromas.]
Taking a queue from my Tanqueray analysis, I did not collect fraction 7 and 8, believing there was no useful information.
Fraction 1: Slice of freshest juniper aroma (but not complete!). Perfectly clear and no evidence of louching.
Fraction 2: More juniper aroma, but of a different weight, but not exactly a different intensity. Another incomplete juniper fragment.
Fraction 3: Juniper transitions into beginning of coriander spiciness. Emerging roundness.
Fraction 4: Absolutely massive aroma and my best guess is that cardamom dominates. The question is of what possible character spilled over from fraction 5. The penetrating intensity is really amazing. This was too concentrated to drink.
Fraction 5: Orange-y notes and terpene aromas I would call persistent, but nowhere near as penetrating as fraction 4. There could be chamomile evident. Palatable.
Fraction 6: Very light in aroma relative to the other fractions. No distinct character. I feel validated to have not collected 7 or 8.
It is hard to say how well preserved the sample is. Did any aromas decompose over the years? Who knows! (I guess a way to know may be to learn what botanicals were originally present and what we could pick out today.) There was no appreciable evaporation to the original bottle. There was also no inharmonious character to any fraction. If we consider the product a perfect time capsule, I’d say it doesn’t hold a candle artistically to present day Tanqueray which is far more complex.
What I’d like to know is the magnitude of my error and how badly I pushed important aroma across fraction 5 into 4. I suspect the intensity of the cardamom overshadowed other nuance.
The better we can analyze role model gins and get the lay of the land, the more our gins will become only limited by our relationship with beauty.