How-To & Diy

How to Blanch Herbs for Syrups + a Mojito

All week long, Jeffrey Morgenthaler of Portland's Clyde Common and Pepe Le Moko will be sharing recipes and techniques from his new book, The Bar Book: Elements of Cocktail Technique. Follow along to win one of five copies we’re giving away -- and to perfect your at-home cocktails.

Today: A trick for herb-infused syrups that won't turn brown, and a mojito recipe that you can make for a group, without spending the whole night muddling. 

 Mint on Food52

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I desperately wanted to put a Mojito on the cocktail menu at my first restaurant job back in 2001. It was a big, busy place and after a couple of hectic weekends, I realized we needed a faster way to prepare this labor-intensive drink. And thus the mint simple syrup was born. The only problem was that steeping fresh mint leaves in hot simple syrup, as we did, resulted in a syrup that turned brown after only a few hours and left us with a rather unappetizing-looking cocktail.

More: Learn how to make symple syrup without any heat. 

Hilariously, our solution back in those days was to add Midori for a little green coloring and name the drink an “Asian Mojito.” Had I known better, we could have saved more than a few palates from that sickly sweet concoction we were serving. 

Herb syrups prepared in this fashion turn dark because of a process called enzymatic browning: Substances in plants called polyphenols allow enzymes to cause browning when they come in contact with oxygen. Your herb syrup may look clear or a lovely shade of light green when you first make it, but once you’ve exposed it to oxygen, it can darken to an unappealing shade.

The way to stop those enzymes from doing their thing is by subjecting them to a little heat. For that, we use a cooking technique called blanching. Blanching simply entails boiling something for a few seconds (or up to a few minutes for vegetables) to deactivate the enzymes, and then stopping the cooking process by plunging the ingredients into ice water to maintain their fresh flavor.

Mint Simple Syrup on Food52  Mint Simple Syrup on Food52

To blanch your herbs, bring a large pot of water to a boil. While you wait, put some cold water and ice into a medium bowl, and arrange a double layer of paper towels on the counter. 

Once the water is boiling, gather your herbs. Don’t pick the leaves; simply leave them on the stalk for now. Holding them by the ends, plunge the stalks into the boiling water. I blanch softer, more delicate herbs (such as mint, tarragon, and basil) for 15 seconds, and hardier herbs (like thyme and rosemary) for 30 seconds. 

More: Read up on everythink you need to know about mint, basil, and thyme.

Once the time is up, remove the herbs from the boiling water and plunge them immediately into the ice bath. Let them stay there for a full minute, remove them from the water, and pat them dry with the paper towels. 

How to Make Simple Syrup  Mint Simple Syrup on Food52

The next step is easy: Remove the leaves, throw them in a blender with premade simple syrup, and blend on high speed for about 1 minute. All that’s left to do is strain out the solids using a fine-mesh sieve, and bottle the syrup.

This little trick is a great way to make mojitos for a big group (say, while hosting a summertime Cuban cookout) and avoid spending the entire evening in the kitchen making drinks. Simply omit the muddled mint from a traditional mojito and substitute this mint syrup for the plain simple syrup. 


Makes 1 drink, easily scaled up

For the mint syrup:

12 ounces water
12 ounces sugar
5 large sprigs (or 7 medium sprigs) fresh mint

For the mojito:

1 1/2 ounces mint syrup
2 ounces (60 milliliters) white rum
1 ounce (30 milliliters) fresh lime juice, plus the spent lime half
Crushed ice
2 ounces (60 milliliters) chilled soda water
Ice cubes
1 bunch fresh spearmint, for garnish

See the full recipe (and save it and print it) here.

We're giving away a copy of The Bar Book every day this week! To enter to win today's copy, tell us in the comments: What's your favorite summer drink? We'll pick five winners at random next Monday, July 21!

Photos by Alanna Hale. Excerpted from the book The Bar Book: Elements of Cocktail Technique by Jeffrey Morgenthaler. Reprinted with permission from Chronicle Books. All rights reserved.

See what other Food52 readers are saying.

  • Kathy
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  • Elina Chernousova
    Elina Chernousova


Kathy April 25, 2016
I know I'm supposed to "add" my favorite summer drink, but I'm still trying to find it. Maybe this book would do the trick!!! I can hope!
Erin July 20, 2014
hobbit2nd July 20, 2014
NicolePDX July 18, 2014
Quick question: any suggestions for the best product to make crushed ice? I just have a regular auto ice maker, and my vitamix turned the ice to powder. Thanks!
Kristina's C. July 18, 2014
It may seem like the hard way out, but I just put regular ice cubes in a strong cloth, wrap it up, and pound it on the pavement until it is crushed! works!
davidpdx July 18, 2014
Online you can find an old-fashioned device called a "Lewis Bag." Basically just a sturdy canvas bag about 10x7 inches. Fill it with three or four scoops of ice cubes, place it on your kitchen counter, and wack it gently with your rolling pin. Perfect crushed ice as course or fine as you want it. I suspect you could make your own if you have access to reasonably heavy undyed canvas and a sewing machine.
NicolePDX July 18, 2014
Aria Portland dry gin & Fever-tree "naturally light" tonic, with a squeeze of lime. Crisp, refreshing and not too sweet. Perfect for a hot summer day in Oregon!
Elina C. July 17, 2014
Sorry, but why do you blanch herbs and don't mix fresh mint and simple syrup in a blender directly? Will mint become brown in it?
Do you use water you have blanched mint in? I mean, perhaps you make simple syrup on it.
Sorry if you have answers in the text. English is not native for me, perhaps I missed something.
sarabclever July 17, 2014
Fave summer drink--probably any sort of sparkling wine-based drink.
AntoniaJames July 17, 2014
So helpful! Excellent post. ;o) P.S. My favorite summer drink? Gin and tonic, preferably on a balcony overlooking the dunes on the Outer Banks. Or my father's retro but fun pina colada, served in the same place.
JasonB July 17, 2014
lorinarlock's Sunset Punch has been a great find this summer:
Kristina's C. July 16, 2014
Great tips, thanks for sharing!
I recently made a spicy grapefruit margarita that was delicious and perfect for a summer afternoon by the pool (jalapeños soaked in tequila for a couple hours and grapefruit juice). I also like juicing fresh fruits and veggies and adding rum, vodka, or tequila to them over lots of ice. Also some great classic drinks that I enjoy on a hot day are Mai Tai's and Pina Colada's! Now... to the kitchen to make me a drink - its 5 o'clock somewhere right!?!
erinbdm July 16, 2014
There are so many good classic ones! Gin and tonic, margarita, mojito. I'm not sure I can choose one favorite!
nedjed July 16, 2014
I love mojito's and whiskey sours
Mallory July 16, 2014
Gin, lime juice, jalapeno, and basil on ice