Imagine this for a moment: Someone hands you a glass of clear water. You lift it to take a sip, but as your nose hovers over it, you are overwhelmed by the smell of oranges, fresh roses, and thyme. Baffled, you look at the glass again. It looks like water. You take a sip—it tastes like water. How?!
Now imagine brewing with that water. Boom.
A hydrosol, or herbal distillate, is an aqueous byproduct from essential oil production. When making essential oils (the kind used in aromatherapy and massage therapy), aromatic herbs and/or fruits are distilled in a copper vessel. The oil floats to the top, and what’s left at the bottom is a hydrosol. Since the aromatic compounds within the herb or fruit are volatile and therefore able to evaporate rapidly, they are the first things to be collected in the distillate. Flavonoids and pigments, on the other hand, are slow to evaporate—if they evaporate at all—and therefore, don’t join the distillate party. In short, through distillation, you can extract and isolate the aroma of any fruit, herb, or flower, and it will condense into the form of water.
Some common examples of hydrosols used in food and beverage applications include rose water and orange blossom water:
Various scented waters are popular in Middle Eastern Cuisine
Fractional distillation is a mouthful, but don’t worry: it’s really quite a simple concept.
First of all, you may remember from Science or Cooking lessons that different things have different boiling points. Water boils at 100°C, but Alcohol (Ethanol) boils at 78.4°C. Meaning that if you boiled a mixture of alcohol and water, the first thing to evaporate would be the alcohol.
The second part of the distillation process is condensation. The evaporating vapors need to be cooled rapidly in order to be turned back into a liquid. Voilà, you have separated alcohol and water.
If you’ve ever had the opportunity to serve in the army, compete on Survivor, or live on the beach, you’ll be familiar with the concept of fractional distillation; it’s a common technique used to get drinkable, potable water from seawater.
For laboratory-precise fractional distillation, the ideal setup would look a little like this:
The perfect distillation setup. Credit: www.erowid.org
But we don’t all live in an ideal world. At Dapper Coffee, we use a significantly less glamourous-looking version that’s just as effective.
How to Create Your Hydrosol
Get a pot that’s semi-deep. Anything that will fit a collection vessel of reasonable height would work; in this case, I’m using a bowl.
Bowl: check. Collection vessel: check. Credit: Dapper Coffee
Gather your aromatics. In this case, I’m making a thyme and lemon peel hydrosol. The more herbs or fruits you use, the stronger the smell. While I don’t have an exact measurement for this, I usually recommend a “healthy handful”.
A healthy handful of thyme and lemon peel. Credit: Dapper Coffee
Fill the pot halfway with water. Cold water straight from the tap works fine.
Adding the water to the aromatics. Credit: Dapper Coffee
Place your collection vessel in the middle of the pot. Leave a reasonable amount of space for the boiling water, otherwise your herb and water mixture could spill over into the vessel.
It wouldn’t be a legit ghetto setup without a broken pot handle, obviously. Credit: Dapper Coffee
Grab a lid for the pot (preferably a convex one with a handle), and turn it upside down. You now have a sloped surface that will direct the condensed distillate into your vessel. Great!
An upside down convex lid is perfect for directing the condensed distillate into your vessel. Credit: Dapper Coffee
Remember the point I made earlier about rapid cooling? I’ve found that a bunch of ice cubes in a ziplock bag makes for a simple and clean solution.
Ice cubes on top for rapid cooling. Credit: Dapper Coffee
Now that your ghetto distillation setup is ready, it’s time to add heat to the mix. Bring the pot to a simmer, but don’t let it become a rolling boil. Boiling it speeds up the process but you might end up with an under-extracted and oddly acidic hydrosol.
Let time work its magic. Oh, and change the ice bag if it melts.
Check out the condensation action.
Credit: Dapper Coffee
Carefully remove the collection vessel from the centre of the pot (it’s very hot). Now, enjoy your magical, aromatic, homemade hydrosol.
Just like magic (or science). Credit: Dapper Coffee
In all organic products, acidic compounds are also highly volatile, meaning hydrosols will always be a little on the sour side. The benefits of the acid are that it prohibits bacterial and fungal growth, but do always remember that hydrosols aren’t sterile—they are a fresh product, like milk, and should always be refrigerated. Over time, a hydrosol can go from a little spritzy to really goddamn sour, so it’s advisable to use them within 2 days of making it.
I’ve done over 30 different flavoured hydrosols since opening Dapper Coffee, and we’ve had our fair share of hits and misses. Anything with flowers has been amazing, rosemary was very overpowering, smoked cinnamon was a little strange, cocoa-orange was intriguing, and coffee was definitely a surprise.
Brewing with a fresh hydrosol is always amazing. We did a V60 with a Kenya AA and a strawberry-chamomile hydrosol once, which was life-changing. An ice drip with anything Columbian and a dark chocolate hydrosol is also delicious.
Hydrosols can also be put into atomisers (aka: spray bottles) to create an aromatised mist. It’s a slightly pretentious presentation, but it works!
Instant scented cloud Credit: Dapper Coffee
For a special event, I once mixed dry ice with a very concentrated caramel hydrosol to create an aromatised pourable smoke. The result was our very own version of a Caramel Macchiato.
Salted caramel crisp, caramel mist, milk foam, espresso Credit: Dapper Coffee
The presentation of the drink was super awesome: you crack the top of the crisp (which also doubled as a lid) like a creme brulee, and the caramel mist comes rushing out. The crisp bits fall into the macchiato and ends up dissolving and flavouring it, so you get a drink with the strength of a macchiato but all the smells and flavours of the Starbucks version.
The flavours and applications for your own customized hydrosol are endless. Give it a go, and let us know your favourite combination!
Written by C. Seah and edited by T. Newton.
Feature Photo Credit: Joel Smedley
Perfect Daily Grind.