20 Mar 2015 Getting to the chemical ‘mystery’ of powdered alcohol drinks
Here’s how NPR.com describes Palacohol:
“The idea behind Palcohol is simple: dehydrated vodka or rum inside a little air-tight package. Tear open the package, sprinkle the powder into tonic water and voila! You’ve got a vodka tonic with an alcohol concentration about the same as a regular cocktail (about 20 proof but the exact alcohol concentration will depend on how much liquid you add).
“In other words, it’s like an adult version of Kool Aid or Country Time Lemonade.”
Anyone with any recollection of middle school chemistry might suspect this explanation is too simple. If you take all the water from vodka you would be left with mostly ethanol, which is a liquid. At least, it’s liquid until you get down below about -114 degrees C.
The key point here is that ethanol is not water with stuff dissolved in it. It’s a compound in its own right – with its own chemical composition. CH3CH2OH.
Now you may notice there are enough hydrogen and oxygen atoms in ethanol to add up to a molecule of water, so in theory there might be a reaction that removes a molecule of water from each molecule of ethanol. Not that this would be easy, since we’re talking about chemical bonds being broken. Indeed, ethanol can be “dehydrated” by heating it with concentrated sulphuric acid. You end up with ethene, which is also known as ethylene.
There are multiple problems with this. Even if you go to all that trouble (don’t try it at home) ethyene is not a solid substance that can be turned into a powder: It’s apparently a hydrocarbon, which comes in the form of a colourless, flammable gas. You’re not going to be sneaking a tank of that into a club and turning it into an instant daiquiri.
This raises the question: How is Palcohol really made?
The majority of the reporting on powdered alcohol seemed to report it as alchemy. That is there was some magic that could be performed on alcohol that would transform it into ‘powdered alcohol’ rather than what was actually going on here, which is basically absorbing alcohol on a powdered matrix, as investigated bt the esteemed US publication Chemical and Engineering News.
The patented process isn’t so mysterious, it turns out. Chemists have known for decades that alcohol can be absorbed by short chains of glucose called dextrins, or even better, by cyclodextrins. One chemist even patented the idea in the 1970s. Popular Science editor Paul Adams recently posted his own recipe online for making powdered alcohol from maltodextrin.
So the alcohol isn’t dehydrated. It’s encapsulated. The downside as, if you’re stuck with the cylclodextrins or whatever else you used to absorb the alcohol, it’s likely to be very sweet.
Being science minded, the C&EN people did their own experiments with the help of food chemist Matt Hartings, who used “the maltodextrin food product N-Zorbit M”.
They found they could make powdered alcohol out of Everclear (95% alcohol) but ran into some trouble with vodka. While other reporters glibly declared that this stuff could be turned into a nice gin and tonic, the C&EN team’s investigation revealed that the results were more akin to “a reasonable facsimile of a sorority house cocktail.”
Hartings mused about Palcohol’s commercial potential. The sheer volume of powder needed for one drink makes it impractical for smuggling into nightclubs, he noted. “But this stuff would be awesome for making alcoholic ice cream,” he said. “If that’s the case, then these guys are really onto something.”
Watch C&EN’s creation of powdered alcohol here…
Related reading:
Sprinkle alcohol on your cereal? US regulators okay powdered alcohol
Powdered alcohol concept stirs up the internet