Demisting & The Spirits Safe

http://www.glenlochy.com/SS_how_it_works.html

http://homedistiller.org/forum/viewtopic.php?f=1&t=19169&start=12

There are many ways to establish the heads cut of a distillate but they never seem to be compared and contrasted under one roof. Some of the techniques have developed and been promoted due to excise restrictions. For example, before self policing, distillers in the UK had to use a locked spirit safe to control the distillate. They were never free to take samples and nose the distillate like the rural mezcal distillers of Oaxaca. Tight excise restrictions, as commented on by S.H. Hastie in the early 20th century, meant you could not pull samples and perform congener analysis which could ultimately lead to time & volume best bets like the sophisticated distillers of Cognac. A hydrometer reading alone is not enough to guide a heads cut, so under the reign of the spirit safe was the time honored tradition of demisting.

Demisting involves taking a sample of the spirits run as it is collected and diluting it with water to see if it louches. The spirits run would continue to be collected in the foreshots receiver until the sample failed to louche. The spirits safe has a compartment with a water supply where this visual test can be conducted while locked (left compartment of the above photo).

At the chemical level, the demisting test is slightly counter intuitive. What is louching is not even from the heads of the new distillate, it is rather residue left in the condenser from the tales of the previous distillate. These congeners from the previous distillate are not so soluble in water therefore as the proof is lowered, they start to come out of solution and louche. If the still is too clean and you essentially have no previous distillate, you cannot perform a demisting test.

The demisting test is therefore like a timer. The heads contain congeners you do not want and you use the ability to visually test for removal of the long chain fatty acid residue from the previous distillation (which you also do not want) to time the whole process. Luckily they coincide fairly well, but often these days the heads cut is pushed beyond the point of demisting clarity to make a relatively lighter spirit.

Failure to make the cut properly (and abandon all cuts) can result in what is called a blank run which is when no cuts are made. The run has to be re-executed but the results will not be the same as normal because the distillate has been effected by time under heat. In the Distiller’s workbook, new distillers are encouraged to not be afraid of making mistakes under the confidence they can toss everything back in the still and start over again. This advice of essentially accepting a blank run is mostly correct in regards to those practicing the handling of the still on the small scale, but on a chemical level, distillers must be aware reactions have happened and the distillate and its various equilibriums are no longer the same.

Obsolete to the biggest commercial distillers, the demisting test may continue to be relevant to low involvement distillers and as a starting point for new projects.

There is a spectacular website devoted to the spirit safe that catalogs all the known safes and has brilliant photographs. I think the owner of the site was the purchaser of this spirit safe when it came up for auction.

A Still Operation Phenomenon Explained

A dynamite book I just got my hands on is Whisky: Technology, Production, and Marketing from the Handbook of Alcoholic Beverages Series. I avoided the book for a while because it was so expensive but it is worth every penny and contains explanations I had been chasing after for years. Believe it or not, I somehow ended up with a few extra copies and if anyone is interested, I would be happy to gift a few to some worthy readers. Send an email.

An issue that had been perplexing me for a while was Germain-Robin’s use of unbleached toilet paper to cover his spirits receiver described in his text: Traditional Distillation Art & Passion. I did not enjoy this book and found it mystified distillation rather than opening it up to new distillers with articulate explanations. I could not find a reference to covering the spirits receiver to catch a copper salt anywhere else and I’ve read quite a bit so I was really skeptical but the guy must know what he is doing. In the text, the copper corrosion in question was attributed in unspecified fatty acids, but in Whisky: Technology, Production, and Marketing (p. 163), it is touched upon and explained differently. Variables I would have never considered are the culprit.

Sulphur compounds present in the distillate vapour are (as with wash stills) highly volatile and odorous substances that take their toll on the copper, forming sulphides; the carbon dioxide in the wash encourages the formation of copper carbonate, which manifests itself as verdigris. It has been customary to suspend a muslin gauze over the spirit bowl to collect any such offending solids that might otherwise find their way into the new spirit.

 

Attack by carbon dioxide and sulphur also thins the copper so that eventually areas subject to this attack (above the boiling line, the shoulder, the swan neck, lyne arm, and condenser tubes exposed to vapour or the start of the worm) wear away, needing constant patching and eventually complete replacement. A still affected by erosion emulates the breathing of a dog, with the shoulders rising and falling in a rhythmic pattern; such a condition is known as panting, and indicates the need for replacement of the pot.

The sulphides (insoluble in water?) & copper carbonate (insoluble in water?) in question here might ultimately be soluble in the alcoholic distillate but they are likely being blown out of the still dry before any vapor comes across, the mechanism being escaping CO2 dissolved in the wine or beer. The spirits receiver being setup in advance so no distillate drips on the floor. The busy distiller possibly hopes to catch the flakes of verdigris ending up on the toilet paper or muslin gauze but if opportunity is missed, distillate just pours right through. In theory, the distillate at this point is collected in the foreshots receiver and re-distilled anyhow.

The solubility of these particular copper salts is dubious so possibly you only catch them because you can. Otherwise they sink to the bottom of the collection vessel. The lack of necessity of catching these forms of exfoliating verdigris may be why it isn’t commonly practiced or better explained in the literature. The practice may just be the hallmark of a distiller, relying more on art than science, who put in his time and soaked up all his habits via good old oral tradition and diligent & studious observation.

Matt Rowley wrote an excellent blog post about replacing worn out sections of stills, which was my introduction to the worn out copper topic, but missed the amazing panting phenomenon described above in the text which must be quite the unnerving spectacle.

Nature vs. Nurture vs. Cocktail: Holistic vs. Salient Creative Linkage

“Westerners also prefer uniqueness in the environment and in their possessions. Social psychologists Heejung Kim and Hazel Markus asked Koreans and Americans to choose which objects in a picture array of objects they preferred. Americans chose the rarest object, whereas Koreans chose the most common object. Asked to choose a pen as a gift, Americans chose the least common color offered and East Asians the most common”. – Richard Nisbett, Geography of Thought

I got into an argument with a brilliant woman I adore and she recommended I read Richard E. Nisbett’s Geography of Thought: How Asians and Westerners think differently… and Why? so naturally I took her advice. The book is interesting on so many levels and does the best job I’ve ever come across of contrasting the two cultures. Nisbett provides excellent background on concepts I only vaguely knew about such as the behavioral significance of coming from an individualist versus a collectivist society. Behavior in this regard, has been linked in countless studies to nitty-gritty perceptual differences such as the ability to detect contrast and remember salient items in photographs. As usual, I wondered if differences of the type Nisbett describes affect any of our flavor preferences and the answer I think is yes which may reveal a lot about a very prestigious flavor mystery.

My position has always been that we have innate drives to seek out the extraordinary as exemplified by Nobel laureate Niko Timbergen‘s super normal stimulus concept, but that may not be the case when you factor in culture as illustrated in the above quote. For decades we have been seduced by the explain-all ideas of genetics & DNA, also that we may be inescapably hardwired for certain behaviors, but this might have denied & downplayed the staggeringly significant power of cultural override.

Nisbett claims that Eastern and Western cultures at times are so different that it has shaped the programming of their attentional spot lights on even the relatively micro level and thus the rest of their thinking. I had previously been influenced by ideas in Slights of Mind: What the Neuroscience of Magic Reveals about Our Everyday Deceptions by Stephen Macknik and Susana Martinez-Conde which led to my teasing out the order of operations of the multi sensory perception of flavor, as confirmed by Spence & Auvray, and ultimately developing the simplified gustation model which explains a lot of the patterns that exist in cocktails. Simplified gustation posits how the path to perceiving olfaction can be flattened when the motive is to compete for attention with the other senses in a flavor experience and win. The idea makes assumptions that things about attention are hardwired. Macknik & Martinez-Conde explain how attention can work so consistently that a magician can manipulate an entire room full of people (with the sometimes exception of the autistic).

But if Nisbett claims Eastern attention can differ markedly from Western attention, can magicians just as easily manipulate rooms of Eastern observers with tricks designed for the West? Westerners often get hung up on foreground salient features while Easterners are more capable of noticing background, relationships, and context which is at the heart of collective thought. Believe it or not, food experiences have all the same attentional features used by the psychologists in studies that Nisbett examines so can any of it apply to flavor?

Westerners focus on objects while slighting the field and they literally see fewer objects and relationships in the environment than do Asians. – Geography of Thought
(p. 109)

Previously the journal, Nature, had published a study, Flavor network and the principles of food pairing, which was exciting and well discussed but came up sort of dry in its conclusions. Inspired by the work of poets, I had been naming the two creative linkage strategies the study described alliteration & collage and I had even singled out a few drinks that typify them which I was recently able to present to some illustrious food scientists after their lecture at Harvard (these chemistry focused guys loved the drinks but seemed to have zero curiosity about categorizing creative linkage). I consider these creative linkage strategies as a means of creating a super normal stimuli and I’ve tried to explain what these experiences do to us and why we return & gravitate towards them (the argument which led to the book concerned those ideas).

Remember, where there is a response tendency, we are creating a delicious exaggerated response tendency through flavor pairing. In Western food, the study found aroma compounds repeated which creates extraordinary, individualistic, salient, foreground objects to pay attention to (hang a set of breast implants on it) while in Eastern food, aroma compounds are typically not repeated but rather linked as a collective collage of relationships. To apply the ideas of Nisbett, the collective collage of aromas appeals to the Eastern mind. Besides the super normal stimulus idea, this new idea of why each creative linkage strategy developed within each culture explains a gigantic piece of the puzzle, which was not seized upon by the study in Nature. We end up with different creative linkage strategies for minds of different attentional proclivities.

But where do we go from here and what is nature and what is nurture? Our nature might only be to pay attention and nurture, or rather culture, might be what to pay attention to. It must be pointed out that we are capable of enjoying and finding powerful repose in each creative linkage strategy. The forces of culture make it hard to create but not to enjoy and this raises some interesting other ideas.

In food, the often utilitarian realm of merely decorated sustenance, some short sighted famous person(s) claim there is no art, and within this criteria being discussed, they might be somewhat correct because according to the paper in Nature, East & West really stick to their patterns. Yet somehow the cocktail came about and things truly got creative, as evidenced by analyzing drinks in the Savoy cocktail book. Something happened to flavor which might reveal a property of artists and that is a unique structure of their attention, and thus ability to construct the world in a way which they can break away from their culture and its sweeping inertia. (Wassily Kandinsky explained this in a very grasping mystical way but it might be useful to psychologists to examine the concept in terms of attention and perceptual differences relative to the surrounding culture.)

Cocktails in the West, even early on, had both alliteration, which I hypothesize is a product of individualism, and collage, which I hypothesize is a product of collectivism. The layman has only the patterns of attention of their broader culture but the artist has their own patterns of attention, and thus own one-person culture (but yes, schools of art do form!). These early cocktail artists were able to see possibilities and create what Western food culture could not for nearly a century.

I hypothesized long ago that the cocktail might actually have led to modernism. Cocktails, which were able to break away from the patterns within food described by the study in Nature, may have dissolved crystallized culture thus incubating artists of other mediums and inspiring them to break away. Of course this is wildly speculative and I have no credentials, but if you look at the time line of art history, the abstract expressionism of the cocktail, a very popular medium, does precede so much other modernism. Hopefully by now I’ve painted enough of a picture that the creative linkage of the cocktail is especially anomalous relative to the rest of food culture.

Long ago I waged war on the word balanced in the culinary arts and tried my damnest to trade it in for the more expansive concept of harmony which I thought better respected acquired tastes. To apply Nisbett, I may have been shifting to an Eastern relatively more holistic mentality, accepting context and the multitude of factors that could effect an experience. As part of my theory of acquired tastes, things are harmonic only in the context that someone possessed the relevant acquired tastes. Balance considered no such context which is typical of Western mentality.

But if Eastern thought has a tendency to emphasize context, should they not have the foremost thinkers on the topic of acquired tastes and flavor theory? I would say no, because both cultures have not developed the categories for which to apply their unique points of view and according to Nisbett, Eastern thought is less concerned with categories. So, flavor, a gigantic hole is our knowledge, is caught between a culture that neglects context and another culture that neglects categories. My work is very big on categories and until you have them, you cannot detect contrast and cannot find patterns to develop theories. Embracing the advantageous qualities of East and West is what it is going to take to unravel flavor, but no need to reinvent the wheel, the harmony concept can borrow ideas from subjects like musicology (cough, cough, Arnold Schoenberg!) which have already seen plenty of intellectual investment. (Kandisnky actually borrowed heavily from Schoenberg to expand ideas about painting and the visual arts.)

Countless people in the food world tell grim tales of how we are hard wired for junk food and unhealthy eating but this meditation on the differences of the East & West show that it may just be culture. Culture comes with serious momentum but it is also quite malleable so our problems can be overcome. But is all this just academic nonsense? Sort of, but it does support and add critical mass to the underdog culture idea. Many of Nisbett’s ideas were supported by ingenious experiments and throwing food ways into the fold adds avenues of potential perceptual experimentation. Many people are also itching to throw cocktails into solid discussions of art history right alongside cubism or abstract expressionism.

What is going to hold a lot of these ideas back is the strange interdisciplinary nature and the lack of a nitty-gritty perceptual understanding of flavor to see these patterns. The culinary world barely recognizes the concept of the multi sensory perception of flavor, most scientists aren’t even aware of the super normal stimuli idea (even though it won a Nobel prize!), recognizing culturally influenced perceptual differences leading to patterns in food ways will make heads spin. These ideas are doomed to be ahead of their time for years to come.

Distiller’s Workbook exercise 15 of 15

Hopped Gin

Hops have one of the most seductive aromas known to mankind with a spectrum that is staggeringly broad so it is amazing that hops have never been widely explored in distillates. Unfortunately, a notorious louching problem is presented by hops which this exercise will explore. The recipe is less explicit than some of the previous exercises because hops vary so significantly. It is recommended to try the many proposed options and enjoy both your successes and cloudy failures in cocktails.

The inspiration for the hopped gin exercise came from the brilliant but seldom imported Japanese product Kiuchi No Shizuku which is produced by the Hitachino brewery. The famous Hitachino white ale is reportedly distilled once to a low proof, briefly mellowed in barrels, and then re-distilled with more hops, coriander, and orange peel. Other similar distillates might be the seldom imported beer schnapps of Bavaria.

Hopped spirits may not be common to the market because of how hops behave when distilled. A clear distillate is very challenging to achieve when working with hops and clarity is something consumers expect out of un-aged distillates. Unlike hopped distillates, most typical distillates become cloudy when certain compounds are included that are volatile only at high temperatures. These compounds can be avoided by making tales cuts below a certain temperature (which corresponds to a certain alcohol level). Whatever clouds hopped distillates, curiously, comes through at low temperatures and is therefore very difficult to avoid because these compounds overlap with (or even are) much of the hop defining aroma. The poorly soluble compound is likely a terpene and could possibly be separated through terpene separation instead of a heads cut where removal could separate other aroma compounds with it.

Hitachino mellows their distillate in barrels at a low proof before re-distilling which presents a clue. Wonderful research on limoncello, to which terpenes are important in defining flavor, state that if the alcohol content goes below 30%, terpenes are at risk of separating as either a louche or possibly an insoluble oil floating on the top. In the Hitachino production process, terpenes could be separated through mellowing at low proof before re-distillation. Stability tests could then be conducted to determine what percentage of terpenes could be reintroduced to the distillate while maintaining clarity at a range of proofs. A practical test for consumers would be making a chilled shot while maintaining crystal clarity.

Terpenes, which have a piney character, are often separated during the production of citrus essences and the process is described well by Joseph Merory in his text, Food Flavorings. The essential oils spend time in a conical separator where the terpenes accumulate on the surface as an insoluble oil that is easy to separate. Terpenes are also reportedly separated from commercial orange liqueurs due to concerns with either their solubility or possible concerns with their stability as an aroma. Conversely, as previously mentioned, terpenes are critically important to limoncellos where they contribute unique timbre and terroir, but also from the limoncello literature, terpenes reportedly can change detrimentally due to hydrolysis.

A concern about hopped distillates which can be explored (with self control not to drink it all!) is whether they change markedly over time which might be a reason they have never been common to the market. Hops are so magical an aroma that you would think every major gin distiller has explored them but perhaps taken a pass due to consumer notions of the stability of distillates. Certain hop distillates explored during development of this exercise have sat around longer than a year and some varietals seem to have lost aroma though age-ability trials were never set up systematically so no conclusions can be drawn for sure. There is also unexplored concerns whether the compound responsible for skunking beer is volatile and could effect a hop distillate stored in clear bottles. Supply chain management is much different than it used to be and with a more educated consumer base, there might now be room for a hopped distillate with a best by date.

The recipe tries to present an elegant starting point for hop aroma that works for nearly every varietal, but if the goal is to learn more about terpene management it may make sense to distill a concentrate, lower the proof, patiently separate the terpenes, re-distill, blend down with plain gin, then re-introduce the terpenes while doing stability tests.

RECIPE

500 mL dry gin (Seagram’s)

8 g hops (Cascade is a good place to start, but experiment with numerous types)

Mix and re-distill together on high reflux until the thermometer on the still reads 93.33°C. Going past 93.33°C may result in a cloudy distillate for other reasons.

Using your hydrometer re-cut the distillate to your desired proof (recommended 80-90).

Hops vary in the potency of their aroma. If the hop distillate is too aromatic it can always be diluted with more plain gin.

It may also be rewarding to collect the product one ounce at a time in small canning jars then dilute them one at a time from the beginning into the first half of the hearts to reduce the proof by 50%. This will illustrate how the first fractions louche. The distillate can slowly be married from the back to the front exploring the sensory contribution of each re-introduced fraction.

COCKTAILS

I.P.A. → I.P.C. (Imperial Pegu Club)

1.5 oz. Cascade hopped gin

.75 oz. triple-sec

.75 oz. lime juice

dash Angostura bitters

 

hopped Negroni

1 oz. Pacific Jade hopped gin

1 oz. sweet vermouth

1 oz. Campari

expressed oil of grapefruit peel

 

hopped Gin Fizz

1.5 oz. Chinook hopped gin

.75 oz. lemon juice

.75 oz. simple syrup (1:1)

top with soda water

Distiller’s Workbook exercise 14 of 15

[This recipe is the accumulation of many years of playing around and connecting the dots. It will likely make your head spin at first but give it a try. Please, if you have any criticism, leave a comment.]

Fernet Aromatized Maraschino Cherries

Distillers can do more than just make distillates and this exercise explores some of the possibilities. Here we are going to make a modern and very much in vogue version of the alcohol preserved maraschino cherry as well as propose some ways to deepen involvement and eventually refine the process. The exercise will have no explicit recipe because the inputs are so dynamic but rather just guidelines and formulas that never extend beyond simple algebra and can be followed to give a rewarding product.

Lots of research has been done on manipulating cherries, and believe it or not, there is even a one credit course at Oregon State University on the production of non-alcoholic maraschino cherries. The OSU course explores the tricky and certainly novel, but slightly gross process of brining the cherries which will be contrasted with the alternate process used in the exercise.

The often lamented cherries described in the OSU course are brined with preservative sulfites and have their texture enhanced by calcium chloride but that is not the only way to skin the cat. Another exemplary cherry is the Cerise au Soleil of Provence which is relatively minimal in intervention and uses alcohol as the primary preservative. Translated as cherry of the sun, they are aged in jars for the duration of the summer on a clay roof top in the countryside. Alcohol preserved cherries require a fair degree of treatment but nowhere near as much as non-alcoholic versions.

Non-alcoholic maraschino cherries get a bleaching brine primarily to prevent microbial growth but also to remove unsightly browning due to mechanical harvesting. The first bleaching brine features sodium metabisulfite, citric acid & calcium chloride and lasts three weeks while the second bleaching brine features sodium chlorite & glacial acetic acid (crystalized form) and lasts five to ten days. The cherries used in the Cerise au Soleil are thus likely hand picked to avoid bruising which would be readily apparent and preserved in alcohol as a mechanism of respecting their natural color & flavor as best possible which would otherwise be lost. For non-alcoholic cherries, despite aggressive brining, ultimately the sulphite level declines to a point where potassium sorbate and sodium benzoate have to be included in the sugar syrup to maintain stability.

Bleaching non-alcoholic maraschino cherries strips them of most all aroma which eventually has to be replaced and is typically done with benzaldehyde derived from the cherry pits which has the aroma of almonds. Dilution of aroma happens to alcohol preserved cherries when they come to equilibrium with the preserving solution they rest in but is overcome by using a spirit of the same aroma so it essentially diffuses in two directions. This means alcohol preserved cherries are best preserved in Kirschwasser which is a cherry eau-de-vie, but other aromas can also be added which will be explored in the exercise.

The calcium chloride of the first brine, in a certain pH range (which explains the citric acid), reacts with the pectin in the cherries, greatly firming the texture and facilitating mechanical pitting. Alcohol preserved cherries are not firmed with calcium chloride and typically have their pits intact to reduce opportunities for browning. No literature states that alcohol preserved cherries cannot be firmed with calcium chloride and it may be a worth while avenue for exploration. Sulfites reduce enzymatic browning and the mechanism is explained well by the OSU course literature. It may not be possible to pit cherries that have not been brined with sulfites without inducing browning. The browning that does form as a result of mechanical harvesting is not actually bleached by the sulfite brine but is rather bleached by the sodium chlorite brine. To avoid using the brining method, the cherries needs to be as carefully handled as possible.

Sugaring the cherries requires a lot of care and consideration. The cherries need to be sorted by density so they can be uniformly sugared. Not all fruit achieves the same ripeness which means that the fruit from a bushel of cherries will have a wide range of sugar contents. If the cherries were mixed randomly, some would sink in the alcoholic preserving solution while others would float. The cherries that floated above the surface would be subject to more oxidation which is what we are trying to avoid. Cherries can be sorted by first estimating the range of their sugar contents then creating a series of testing bins (sugar-water solutions) to see which cherries float and which sink. The bins can vary by 20 g/L increments. Cherries with higher sugar contents will sink while cherries with lower sugar contents will float. To see where they find equilibrium, the cherries will have to be shuffled between the bins. When there is extreme variance between the sugar content of the cherries and the preserving solution, the cherries with less sugar will lose water and shrivel while the cherries with more sugar will take on water and swell, in both cases causing tissue damage.

To get a rough estimate of a cherry’s sugar content, it is helpful to use a wine maker’s brix refractometer which is a small prism that a single drop of cherry juice can be placed upon. The refractometer has a sight glass with a scale that can measure the sugar content via the refractive index of the juice. A refractometer can measure (estimate) sugar content only in non-alcoholic solutions. The beauty of the refractometer (as opposed to the hydrometer) is that it only takes a single drop to get a reading, but the readings will need to be converted from brix to g/L to make the numbers more intuitive to use. Wine makers use refractometers out in the vineyard to estimate the ripeness of single clusters of grapes as the season progresses while bartenders use them to calibrate their various syrups.

The OSU course teaches a valuable lesson about sugar content which is if it starts at the same level of the cherry it can be walked upwards in slow increments to a desired point without tissue damage. Non-alcoholic cherries typically have a sugar content of 470 g/L which of often more than 3 times the starting sugar content. The sugar content can be increased by 30 g/L every 12 hours until the desired level is achieved which for the exercise may just be high enough that 90% of all the cherries can be brought up to a uniform level.

For alcohol preserved cherries, the sugar content is integral to determining the alcohol content because sugar displaces alcohol lowering the proof. Alcohol fortified products are often brought up to the minimum of microbiological stability by alcohol alone which is typically 18%, but that is not the only approach. An idea in dessert wine production exists which lowers the minimum necessary for alcohol as a preservative by measuring and harnessing the preservative power of the sugar content and sometimes other variables like pressure in the case of sparkling sweet wines. Great research from Maynard Amerine at UC Davis explores this stabilization concept and the lessons learned can be applied to far more than just this exercise. Preservative power is counted in Delle units, named after the Russian inventor, Professor Delle, in the early 20th century and stability is often thought to happen at 80 units. To calculate Delle units the formula A + 4.5C = DU is used where A equals the sugar content in brix and C equals the alcohol content. If a sugar content of 18 brix is achieved, an alcohol content as low as 14% can be used to achieve 80 Delle units. Eighty units is not a hard and fast rule but rather just a point to begin trials and exploration.

An alcohol content at the minimum of stability is critical due to a strange sensory phenomenon where the haptic heft of the solid fruit changes the threshold of perception of alcohol making it seem much more alcoholic than it actually is. This same effect can be seen when eating the pineapple chunks from a Stoli-Doli jar. Many people wrongly believe the fruit holds more alcohol than the liquid, but the illusion is just one of the many phenomena of perception. The same phenomenon will also enhance contrast detection of the fernet aroma we are going to add, and even though fernet will only represent 10% of the preserving solution, eating a cherry may feel as though one is taking an entire shot of fernet.

Many people have the notion that alcohol is a complete preservative, but while it does prevent bacterial growth and certain levels can even kill bacteria, it is powerless against oxidation and even enzymatic browning. If you have ever seen a pear trapped in a bottle of pear brandy, besides the alcohol, ascorbic acid (and possibly sulfites) is also keeping the pear company, otherwise it would brown detrimentally. To preserve a pear, the advice is often given of using 1 g/L of ascorbic acid in the preserving solution (as well as rinsing the fruit and bottle with a sulphuric acid solution to kill bacteria on the surface of the fruit), and with cherries we recommend following the same advice as well as vacuum sealing the canning jars to remove trapped oxygen. Ultra violet light from spending time on clay roofs in the sun may also kill bacteria in the case of the Cerise au Soleil.

Considerations need to be made for the alcohol content of the cherries. When the preserving solution rests with the cherries, the alcohol content will come into equilibrium and be reduced, therefore the displacement of the cherries needs to be known. The displacement of the cherries can be found by taking multiple small samples from each bin that differ by density and placing them in a graduated cylinder of water. The weight of the sample can divided by the observed volumetric displacement to find a ratio which can be extrapolated to find volumetric displacement with only the weight of the entire lot.

Awareness of the Delle stabilization concept can either allow a minimal alcohol content for those that deepen their involvement and experiment systematically or it can just provide a very comfortable margin of error.

Every division of the sorted cherries is going to require its own custom preserving solution and the lowest sugar content cherries need a slightly higher alcohol content if the sugar content is going to be walked upwards. Keep in mind, every 30 g/L increase in sugar content has dissolved volume of 18.9 mL which can dilute the alcohol content by nearly half a percentage point and it may take almost two rounds of increasing the sugar to reach that of your ripest cherries. If you are not making your own cherry eau-de-vie, Hiram Walker’s Kirschwasser is the most practical alcohol base. As a starting point, it may also be useful to put each batch in wide mouth canning jars that assume the cherries will displace the same volume as the preserving solution (one volumetric liter of cherries is preserved in one volumetric liter of preserving solution).

Hiram Walker Kirschwasser is only bottled at 45% alcohol which means that once it is diluted by sugar then brought to equilibrium with the cherries in a 1:1 ratio, the equilibrium alcohol content may be lower than is needed. This problem can be solved by either changing the preserving solution ratio to use more Kirschwasser per volume of cherries or by re-distilling the Kirschwasser to concentrate its alcohol content. Simple tests with water will tell if your cherries can be covered by a desired volume of preserving solution or if adjustments needs to be made.

Introducing additional aromas like the saffron-menthe of fernet can push a preserved cherry into something that is over the top and very special. Fernet cannot be re-distilled with the Kirschwasser because it contains a valuable non-volatile fraction which contributes gustatory-bitterness therefore it has to averaged in. Fernet also has a sugar content of approximately 30 g/L.

If need be, re-distill Kirschwasser on low reflux until the thermometer on the still reads 97°C (the high temperature did not seem to produce a cloudy distillate because it had already been cut previously during the production of the inputs).

Add Fernet to the Kirschwasser so that Fernet’s alcohol content represents only 10% of the blend. At 10% of the preserving solution, Fernet’s  30 g/L sugar content will be diluted to 3 g/L before further dilution. It may be safe to consider this sugar content negligible.

The resultant mixture of Kirschwasser and Fernet will have to be cut to match each specific batch it is going to fortify. First cherries displacing one liter needs to be found. At this experimental scale, a two liter graduated pitcher can be filled to one liter with water and cherries can slowly be added until the water level rises to two liters. This liter of cherries will require one liter of preserving solution. The preserving solution will be constructed to match the sugar content of the sorting bin the cherries were taken from. The displacement of the sugar will need to be found to find the corresponding alcohol content. The dissolved volume of a weight of sucrose can be revealed by dividing the weight by the density of sucrose, 1.587.

To find the corresponding alcohol content we can use the equation: (1000 mL – sugar vol. mL (X%))  = 1000 mL (desired final alc.%).

The X variable represents the alcohol content necessary before dilution by sugar to hit the target alcohol content for a single liter. The volume of alcohol necessary per liter is simply 1000 mL – the dissolved volume of sugar. Working this out per liter means it can easily be scaled for any custom batch size.

Now that the preserving solution has been cut and sugared, ascorbic acid will need to be added and completely dissolved. One gram should be added for every liter of preserving solution. The density of ascorbic acid is 1.65 g/mL thus one gram will displace 0.61 mL and probably can be considered negligible.

After the cherries are added to the preserving solution they should be de-aerated to remove all the oxygen clinging to the cherry skin if possible. Pressure de-aeration in a Cornelius keg is a viable option for large batches and vacuum de-aeration with a canning jar lid attachment is effective for very small batches.

If need be, the sugar content of the cherries should be walked upwards to hit a target and the influence of this addition on the alcohol content should always be a accounted for with simple averaging. If the alcohol and/or sugar content becomes lost, a sample of the preserving solution at equilibrium with the cherries can be re-distilled to reveal the misplaced alcohol and sugar figures.

If the cherries are left unpitted time will eventually cause the alcohol to pull the aroma of the pits into the meat of the cherry. If fernet was added to the preserving solution at the recommended scaling, the same phenomenon of perception that decreases the threshold of perception of alcohol, thereby amplifying it, will also amplify the aroma of the fernet making the indulger believe far more fernet was included than the actual.