[If you’re reading this to make hand sanitizer during a shortage, keep in mind the big lesson is that you can dehydrate a commercial sample (and weigh the dry matter) to learn how much gelling agent they used. Back then I was only aware of polyacrylic acid, but another option may be CMC E466 which is found in gelified baking rum.]
[this is written to probably reappear as the last exercise]
Non-potable Pure Pot Still Purell; Wormwood Aromatized Hand Sanitizer
By now most readers probably want to wash their hands of all this distillation talk, but there is one more fun idea that should be considered. Distillation can produce more than just drinkable beverage alcohol, it can also churn out non-potable, antiseptic, sanitary ethanol of which hand sanitizer is a popular and useful form. Making your own aromatized hand sanitizer is a simple process that borrows from the skill set of the beverage distiller. This exercise can also illustrate little understood concepts in aroma perception.
Hand sanitizers are typically just blends of ethanol and other non-potable alcohols such as isopropyl held in a loose gel with a soup of strange alcohol tolerant gelling compounds. One likely gelling compound is polyacrylic acid which is used in baby’s diapers for its water absorbing capacity. The gel helps keep the hand sanitizer clinging to the skin long enough to disinfect. The soup of gelling compounds is very hard to assemble from scratch, but luckily you would never have to. The gelling compounds can easily be isolated on the nano-scale by de-hydrating a commercial hand sanitizer in a kitchen dehydrator such as an Excalibur brand whose removable shelves turn it into a big dehydration box. The dehydrated gelling compounds can be reconstituted at any time.
These gelling compounds are also heat tolerant enough that they can be separated from the volatile, but non-potable blend of alcohols in a commercial hand sanitizer by simple distillation. What is left at the bottom of the pot are the gelling agents and water which can then be transferred to the dehydrator. The recovered non-potable blend of alcohols can be re-distilled with an added aroma source and concentrated further to the necessary proof before being reunited with the gelling compounds.
For hand sanitizer to kill bacteria within a reasonable contact time, the final alcohol content needs to be above 60%. Most hand sanitizers are above 62% to compensate for potential evaporation and a few products on the market are as high as 70%.
An aroma source that has long taunted bartenders has been perfume. The aroma of perfumes and their cousins the aftershaves can often be fantastically complex and definitely extraordinary. Many a bartender has thought of applying a drop of fragrance like one would a dash of bitters. Unfortunately, many fragrances are constructed with non-potable alcohols as well as synthetic fixatives to reduce volatility and should not be consumed.
The stylishly retro aftershaves by Pinaud are a great way to explore the distillation of fragrances. A hydrometer implies that Pinaud’s after-shaves are nearly 70% non-potable alcohol and they also have just enough aroma that they do not become obnoxious if you apply more than just a drop. When re-distilled so the non-volatile fixatives are separated, they also fade fast so the experience doesn’t begin to haunt the user. Re-distillation of alcohol based aftershaves separates unwanted non-volatile additives and concentrates the non-potable alcohols so that they will be sufficiently antiseptic once they are diluted with the gelling compounds.
These exercises are definitely always beverage focused so to explore these retro aftershave based hand sanitizers in more of a beautiful, but admittedly very high concept context, imbibers can apply the sanitizer to their hands then proceed to enjoy a drink. Due to proximity when they take a sip, the imbiber smells their own hands but they almost seem as though they are not their own. It is almost like rubbing elbows with someone else; or somewhere else; or even somewhen else. In trials, it was found that aroma sets like those of the Pinaud fragrances, which seem to neatly connotate a place in time (the 19th century), to be an interesting garnish.
Mono aroma hand sanitizers can be useful teaching tools. Many people in the culinary arts require the antiseptic function of a sanitizer, but could also benefit from repeatable exposure to unique scents as a means of cementing their memory. It even turns out that aromas are best learned passively rather than actively so exposure as a byproduct to another routine task might be the best way to learn. The opportunity to explore the volatility of botanicals in unique distillates can also be very valuable. Even failures can teach lessons. If distillates are no fun to experience by drinking, the lessons might be best learned by application to the hands. It is easy to envision common aroma flaws in distillates as well as unique aroma markers, such as where to make a tales cut, being captured in hand sanitizers as an avenue for teaching.
Repeated use of the hand sanitizers can illustrate a little understood idea in aroma perception that can have profound implications for the distiller. Repeat exposure to an aroma under certain circumstances can change its threshold of perception leaving an expert with a unique reality. The mechanics of sustained contrast detection change is best explained in Gordon Shepherd’s primer on the neuroscience of olfaction, Neurogastronomy. In certain instances an expert in a particular aroma can smell it when others cannot. Repeated use of the wormwood hand sanitizer was shown to change contrast detection in certain wines, but strangely the effect did not last. It needs to be remembered that distillates are produced to be drunk by non distillers who have no unique training with the specific aromas. Distillers eventually hit the limitations of highly subjective organoleptic analysis and need to turn to sophisticated, objective, quantitative analysis. Sufficiently exploring this exercise can demonstrate these ideas.
RECIPE:
To separate gelling compounds from non-potable alcohol via distillation:
1000 mL commercial hand sanitizer
200 mL distilled water
Combine the ingredients and re-distill on high reflux until the thermometer on the still reads 93.3° C. Water is added to prevent the gelling compounds from getting too thick and potentially scorching on the bottom of the pot. Distilled water in particular is recommended to minimize any impurities getting introduced into the product and discoloring it. The thick gel can be removed from the pot with a standard kitchen spatula.
The salvaged non-potable blend of alcohols can then be re-distilled with an aroma source such as wormwood. To obtain suitable aroma intensity, add 50 grams of wormwood to the volume of non-potable alcohols recovered from 1000 mL of hand sanitizer.
Mix and re-distill on high reflux with the goal of concentrating the distillate as much as possible.
The gelling compounds need to be dehydrated such that when they dilute the non-potable alcohol, the alcohol content will be above 62%. At this point the gel is in a pan in the dehydrator and it is difficult to gauge its volume. Luckily the gel is mostly water so each gram of gel will displace close enough to one mL. If the weight of the pan is known it is easy to find the volume of the gel by identifying its weight.
With an alcohol content such as 80% and a known volume, a weight for the partially dehydrated gelling compounds can easily be calculated with simple algebra.
A sealed canning jar in a hot water bath can be used to integrate the gelling compounds with the non-potable aromatized alcohol blend.
Once the project is complete make sure your equipment is thoroughly cleaned before returning to any beverage production. Few people enjoy isopropyl alcohol in their gin.
RECIPE
Aftershave based hand sanitizer
12 oz. Pinaud aftershave (our favorites were their Bay Rum and Lilac Vegetal)
100 mL water
Combine the ingredients and re-distill on high reflux until the thermometer on the still reads 93.3° C. Water is added to prevent the non-volatile compounds from getting too thick and potentially scorching on the bottom of the pot.
A 12 oz. bottle of aftershave yields enough non-potable alcohol for 8 oz. of hand sanitizer therefore to obtain the necessary gelling compounds, 8 oz. of commercial hand sanitizer needs to be sufficiently dehydrated.
The gelling compounds need to be dehydrated such that when they dilute the non-potable alcohol, the alcohol content will be above 62%. At this point the gel is in a pan in the dehydrator and it is difficult to gauge its volume. Luckily the gel is mostly water so each gram of gel will displace close enough to one mL. If the weight of the pan is known it is easy to find the volume of the gel by identifying its weight.
With an alcohol content such as 80% and a known volume, a weight for the partially dehydrated gelling compounds can easily be calculated with simple algebra.
A sealed canning jar in a hot water bath can be used to integrate the gelling compounds with the non-potable aromatized alcohol blend.
Once the project is complete make sure your equipment is thoroughly cleaned before returning to any beverage production. Few people enjoy isopropyl alcohol in their gin.
COCKTAILS
Absinthe & Water
2 oz. absinthe
x oz. water (8 oz. on good days and 4 oz. on bad days)
before serving, have the imbiber apply eau-de-wormwood hand sanitizer
Hanky Panky
2 oz. gin
1 oz. sweet vermouth
barspoonful Fernet Branca
before serving, have the imbiber apply Bay Rum hand sanitizer
Garden Variety
.75 oz. green chartreuse
.75 oz. creme de cassis
.75 oz. lime juice
top with 3 oz. sparkling wine
before serving have the imbiber apply Lilac Vegetal hand sanitizer
This article is a good example of how the distillers or even distilleries can help out with sanitizer shortages during this pandemic!