I’m a big fan of studying role models so it was great fun to deconstruct an exemplary fruit eau-de-vie with the birectifier. The example chosen was a vintage of St. George’s Aqua Perfecta from four or five years ago. Fraction five turned up a big surprise developing an emulsion of terpene based essential oil very much like rum oil.
1. non-culinary aroma (IMO perfect level of ethyl-acetate)
2. nothing abnormal
3. nothing abnormal
4. fusel oil mixed with pear aroma
5. cloudy, penetrating, angular if not spiced character. not too palatable. like drinking perfume!
6. fresher pear aroma, slight acidity
7. fresher pear aroma, slight acidity
8. very subtle stewed applesauce kind of character. discernible acidity on palate
To taste, I used the modified German protocol where 5 ml of the first four fractions are diluted 3x while 5 ml of the last four fractions are diluted 2x. This leaves 20 ml of each fraction to perform other tests later.
The first fraction appeared to be spot on. The aroma was very generic with no character to indicate it came from a particular spirit. The ethyl acetate level, under the protocol, was just at the level it is perceived as non-culinary (read previous post to understand that if you need to) which experience is showing to be perfect. I had just tasted the first fraction of a supposedly full bodied locally made rum the other day, that was way too light. Aqua Perfecta nails it!
The next two fractions which I often call alignment fractions showed nothing abnormal positive or negative.
The fourth, or fusel oil fraction, seemed very normal and contained a small amount of pear aroma. When considering the high quality of the fifth fraction, you wonder if St. George did anything particular to nail this fraction so well. Excesses of fusel oil that needs cut away jeopardizes the fifth fraction.
The fifth fraction was sensational. I never imagined that pear eau-de-vie would contain a rum oil-like emulsion, but it is known that Cognac does possess one. Dr. Luckow describes one existing in kirschwasser, but not in plum brandies though that does means it isn’t possible. Producers of the 1930’s may just not have had the technique yet if they were commodity orientated (I’m itching to compare a Hiram Walker’s commodity kirschwasser to a fine European example.
Aqua Perfecta fraction five was like drinking perfume, that is to say stunning but so concentrated as to be barely palatable. Countless questions are raised. And, Randall Grahm told me there was a trick to fermenting pears, but he didn’t tell me what it was… Was this quality from particular fruit cultivars or the yeast or a text book fermentation?
Fractions six, seven and eight showed nothing out of the ordinary. A fresh pear aroma lingered through six and seven. Eight exhibited a subtle stewed fruit aroma, but that seemed right where it should be. Aqua Perfecta lived up to the name.
The funny and tragic thing about this spirit is that I bought it as a deep discount close out (four cases of it!). The market did not understand how exemplary it was. An emerging question becomes, can we use the birectifier as a marketing tool to promote the visible, rare, divine in fraction five? Can rum oil and the resurgence of the legendary Jamaican producers, which the birectifier proves to really have that je ne sais quoi (glycoside and carotenoid derivatives), also elevate other spirits categories with the same characteristics? I bet yes!
An extra note to get the gears turning is that I bet the birectifier could be used on small samples of fruit brandy ferment pre-alembic distillation (scaled to 100 ml of absolute alcohol) to help identify unique properties among cultivars, optimize phenolic ripeness, and tune fermentation parameters such as yeast selection and pitching density.