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I believe we've done the work to call this the ultimate Gin and Tonic recipe.
After several attempts to make an exceptional homemade tonic syrup - including this famous recipe from Jeffrey Morgenthaler, and this one from Lottie + Doof, via Tony Cecchini and the NYTimes - Keith and I were unsatisfied. In all cases, we liked the tonic, but we didn't love it. Our biggest complaint - we couldn't taste the gin.
Gin is divisive, isn't it. Do you know anyone who's on the fence about it? People seem to either shrivel in horror or swoon with delight at the mention of it. Those who swoon like the flavor of gin, and why? Because it's loaded with botanicals - primarily juniper, but look at this list of other essences you might experience.
After each attempt at a homemade version, we would end up back with our favorite store-bought tonic, Fever Tree Naturally Light. It's light, not in a phony sugar way, but in a less-sugar way - a plus as most store-bought tonics are ridiculously sweet. It's only slightly bitter, and has a fresh citrus flavor. But it's also understated, too much so once you've tried a homemade version. So it was our muse, but we hoped for something even better.
How to Make Tonic Water
We started the experiment to create our own recipe with 3 criteria:
- The syrup had to be delicious, but subtle enough to accentuate, not overpower the gin flavor.
- It had to be cold extracted because cooked citrus zest tastes, well, cooked.
- It needed to be just barely sweet and pleasantly bitter.
We decided to try 2 versions - both had the basics: cinchona bark (the natural source of quinine), and citric acid (necessary for extraction and helpful for preserving).
The first version had just citrus zest and lemongrass. The second had zest, lemongrass, and other botanicals: cardamom, lavender, allspice.
We filled our jars with filtered water, shook them daily, and allowed them to steep for 72 hours. I firmly believed that the version without the additional botanicals would prevail.
I was wrong, sort of.
Think of vanilla extract. Take in that incredible aroma and you're tempted to take a swig. Or you were tempted before you tried it straight the first time. On it's own, the extract is bitter and pungent. But in the proper proportion, added to a sugary or savory recipe, is matchless. Tonic syrup is like that.
You can't try a couple of syrups straight and determine which is superior. You have to make a proper drink and try them side by side. Work, work, work!
We did our careful taste-testing and were surprised by the result. Both were excellent. Both were missing something. So we took a chance and combined the two. And, Success! Really, the BEST gin and tonic either of us had ever tasted.
What began as rivalry ended in alliance.
More Classic Cocktails
And if you're interested in trying other delicious classic cocktails, I recommend the very herbaceous Last Word Cocktail, this Boulevardier Cocktail recipe, this Peach Bellini recipe, and this French 75 Cocktail!
Recipe Update: Several people asked about ingredient weights and I finally got around to weighing as I went - because really, there can be a huge difference in size from one citrus fruit to another or between stalks of lemongrass.
I've also increased the amount of rich simple syrup based on recommendations (looking at you, Ken Smith 🙂 ), from several people who commented on the original post - it still only comes out to be 1 ½ teaspoons of sugar per drink and really does make for a smoother, more balanced flavor. However, if you prefer your tonic more tart / bitter, stick with the original amount of syrup: 2 cups sugar and 1 cup water.
Homemade Tonic Water Recipe Video
Homemade Tonic Water for the Ultimate Gin and Tonic
- 3 cups water (675 ml)
- ¼ cup chopped cinchona bark (1 ounce / 28 grams)
- ¼ cup citric acid (2.2 ounces / 62 grams)
- 3 limes peeled zests only (0.4 ounce / 11 grams)
- 3 lemons peeled zests only (0.5 ounce / 14 grams)
- 2 oranges peeled zests only (0.5 ounce / 14 grams)
- 3 stalks lemongrass tops and bottoms trimmed and outer leaves removed then sliced into ⅛" to ¼" rounds (2.5 ounces / 71 grams)
- 4 whole allspice berries
- 3 whole green cardamom pods
- 1 tablespoon lavender
- ¼ teaspoon kosher salt
Rich Simple Syrup
- 3 cups natural cane sugar (21 ounces / 600 grams)
- 1 ½ cups water (355 ml)
You'll also need:
- Lime wedges
- Sparkling water
- Combine all ingredients except rich simple syrup in a sterilized, one-quart lidded glass jar. Shake to combine. Refrigerate 72 hours, shaking occasionally, at least once per day.
- Make rich simple syrup: dissolve 3 cups sugar in 1 ½ cups water over medium heat until sugar is completely dissolved. Allow to cool. Transfer to a container and refrigerate.
- After 72 hours, strain tonic mixture into a large glass pitcher. Strain tonic a second time, using a coffee filter or very fine cheesecloth.
- Whisk simple syrup into tonic until thoroughly combined.
- Pour tonic syrup through a funnel into storage bottles and store in the refrigerator.
For the Ultimate Gin & Tonic
- Fill a highball glass with ice. Add 1 tablespoon tonic syrup, 2 ounces gin, and 2 ounces sparkling water. Stir to combine. Serve with a lime wedge (about ⅙ of a fresh lime). To drink: squeeze the lime wedge into the drink, then drop it in. Enjoy!
Ken Smith says
This is an excellent recipe for tonic. I have made it over a dozen times now. I have made some minor tweaks and one major one... I'm afraid the general public, myself included, don't have the same refined palate as you! Most of the commentary about too sour and too acid is because it needs about half again as much simple syrup. I have been using Domino Demerara sugar at your concentration to make just shy of a liter of finished syrup. This makes a nice color and brings out all the spices to the more plebeian palate. I have recently finished a fairly accurate weight oriented recipe as opposed to volume. I was noting taste inconsistencies - particularly with the lemongrass and the zests. My results in weight lead me to guess you are looking for the same amount of zest from all three fruits, right around half an ounce. Lemongrass comes in around 1.75 ounces. Stalk count versus weight is all over the board, I'm afraid, and it really adjusts the acid and lemon flavors. I also use about double the cardamom and allspice. (about .04 and .07 oz, resp.) Someone mentioned Junipero, which is great gin, as well as Hendricks. Recently I've been making my own gin with the Homemade Gin Kit and refills. I make the gin with about half again as much vodka as recommended (See aforementioned plebeian effect.) What brought all this on is Sodastream abruptly canceling their tonic syrup. Now Schweppes tastes like chemicals to me. If I start a craft tonic business I suppose I will feel obligated to split any profits. Thanks so much, Ken PS: Using an orange slice instead of lime really brings out the spiciness.
Ken Smith says
Also I want to add the best final ratio is 1:7.
Ken Smith says
I realized I wasn't too clear on the simple syrup - notably I left out the word "simple" - I use three cups of Demerara sugar and one and a half cups of water. Conveniently the Domino 24 oz. (weight) package is also about three cups of volume. Last thing I swear: I use a sieve, then a linen cloth, then a coffee filter. Crystal clarity and requires no shaking before diluting.
Well this is one knock-out comment Ken! Thank you so much for sharing all of your findings. I really appreciate the note on weights - it's a great point that stalks of lemongrass are like saying one medium potato. With baking, I love recipes with weights and mixology should be the same. I'm going to try your way in my next batch and eventually will update this recipe with weights to help people (including myself) have a more consistent outcome.
I noticed yours comes out crystal clear. I too used sieve, cheesecloth and then about 15 coffee filters. Mine looks like orange juice! I wonder what I did wrong.
The final tonic water should be an amber color (like the last couple of photos in this post). Do you mean that your tonic water is cloudy?
Amanda Saurin says
Hi Ken and Marissa,
just a quick question, being European I'm a little confused by the cups and so have been trying to make a conversion to grammes or ounces. Ken thank you for your help in this but can you clarify the weight of water? that's the last bit of the puzzle...
A cup of water is 8 ounces or about 237 grams. Honestly, you don't need to be precise with the amount of water - you can just add all of the aromatics to your jar and then fill it up with water. Also note that many commenters have preferred a sweeter version - if something doesn't taste quite right when your tonic is ready, add more simple syrup.
Thank you so much, Ken, for doing the weight work! My heart sinks when I see cups and counts; they're so unreliable. Just a quick question - when you talk about the final ratio being 1:7 is that 1 syrup to 7 sparkling water or 1 syrup to 7 water+gin? I'm grateful too for your comments about the sweetness because I would have cut down on the simple syrup, or made a standard 50/50 syrup, thinking it would probably be too sweet for my taste (most things are!)
No-one seems to have commented on the bitterness. As this isn't something one can adjust to taste without making a new batch I'd appreciate a view on where this recipe sits in this regard, on the understanding, of course, that it's a very subjective assessment!
Now.....if I could get y'all to talk in grams...:-)
I'm the same way when I see a recipe for baking - I only like to bake by weight. I promise that it's on my short list to make a fresh batch of this and update the recipe with weight measurements.
Ken Smith says
One part finished syrup to seven parts carbonated water. I like tall g&ts so I use half a shot of gin to seven or eight ounces of the final carbonated tonic. Lots of ice.
Ken, thanks again for all of your experimenting and input. I just made a fresh batch and went with more simple syrup as you suggested - you're right! Even better... It seems like a lot of sugar, but since you use 1 tablespoon of tonic syrup for each drink and end up with about 6 cups (96 tablespoons) of tonic water between the concentrate and simple syrup, it's about 1 1/2 teaspoons of sugar per drink, not bad. 🙂
Tanya Bokat says
What is the shelf life of the syrup and does it need to be refrigerated?
Great to have stumbled across your blog in the quest for the perfect tonic syrup! Cinchona is difficult to get so I wanted to research before I actually tried making it. I dismissed several recipes off the mark, Jeffrey Morganthaler's because one stalk of lemongrass cannot possibly equal one cup, David Lebovitz (whom I love) because I was suspicious of the cooked citrus thing. Look forward to trying this and will report back - the only thing I was curious about is whether citric acid comes in different concentrations accounting for some commenters finding this recipe on the sour side. I'm going to start with a bit less and tweak as I go. Thanks for doing all the hard work to get us to this point!
Hi there! That's a great question about citric acid - if it's available in different levels of acidity, I'm not aware of it. Good plan to start with less - you can always add more if you want. I think that citrus rind can vary a lot too - in flavor and acidity. So many variables at work! Let me know how it goes... Cheers!
I've made tonic syrup before. This recipe looked intersting so I gave it a go. Way too much citric acid. Way too much! Even diluted with 6 ozs. of club soda it's instant heartburn. I won't sacrifice my gin to a tonic water that I can't even drink straight over ice.
Oh, I'm so sorry that it didn't work out for you. I agree about sacrificing good gin - never a good idea. 🙂 Cheers!
i ve made around 600 G&t at my bar with this recipe, and 99% has been very happy.But the funny thing is that i realized last week that i use 80ml of citric acid instead of 30ml..So this week i am going to try with 30ml.
Wow, you're making it at your bar? That's awesome! Where is your bar? Feel free to leave a link...& let me know how it goes with the reduced citric acid. Cheers!
It's been a compromise, we are using around 50ml.We also use some star anise & cinnamon.
I've compared this with a new tonic in the market here in Sweden.Ours.Yours..:) is way better!
Wow, thanks Marcis! Cheers!
Andy Berndt says
I've made many other tonic recipes, but this had many more tasty botanicals and I was intrigued by the steeping process versus the cooking process. Then I tried. Whoooooooooa. So good! This blew my mind. Loved it! Thank you for sharing this recipe! Took tonic to a whole other level!
aww, thanks so much, Andy! Glad you're enjoying it...cheers!
Vinay Patel says
I had a fund raiser party with 50 people and offered 5 drinks, The only drink that everyone came back or 2nd's and 3rd,s was the G&T. Thanks you very much for the awesome recipe
Even my wife who only drinks wine is now a fan of this G&T
Wow! What a lovely comment - thank you so much for letting me know!
Vinay Patel says
this is the best G&T ever. My wife who is only a wine drinker loves this G&T. I am getting ready to pour this G&T to 50 guests tomorrow. Will post their reactions
You made my day! 🙂
We really enjoyed this. I think it was VERY strong though, so we wound up diluting the syrup with a bit more sparkling water, but the end result was very tasty. We also used empty tea bags (for use with loose leaf tea) to strain the mixture, which worked out brilliantly. Thanks for sharing!
I haven't made your recipe yet, but I was wondering what brands of gin you like in G&Ts. I've been experimenting with the standard G&T recipe and then adding a small amount of St Germaine elderflower liquor and grapefruit bitters, and it's pretty fantastic. I'm excited to replace my generic store bought tonic with your recipe and see how it improves my experiment. Thanks for posting your results.
Hi Mason. That hint of elderflower / grapefruit bitters sounds delicious! Generally we drink a locally produced gin - Cascade Lakes. Or, when we're budget minded Gordon's dry. Have you tried Hendrick's? Honestly, it's a bit too floral for me, but some people LOVE it. Cheers!
Jackie Fein says
Hi Marissa. I made it and I love it but I have a question - how long does your tonic syrup last in the fridge?
Hi Jackie - that's a great questions! We tend to keep ours for a few months. I'm careful to start with a very clean container and always add a splash of vodka to help extend it. Cheers!
Brenda Weller says
Hi Marissa- Do you know how long the Tonic syrup will keep in the fridge? Just wondering about storage life. My hubby and I love Gin & Tonics. Now I want to make your homemade tonic. So excited to try!
I wish I could say an exact amount of time, but I honestly don't know. We've had ours in the fridge for a couple of months with no problem. To help it last as long as possible, be sure you start with a very clean container and splash in a little vodka at the end to extend it even longer. Cheers!
Looks like a great recipe! Trying right now. Can I ask the reasoning behind cold maceration for the water and solid ingredients? Looking forward to the results!
We tried cooking the ingredients a few times and the citrus always tasted 'cooked'. So we decided to try a cold extraction and really prefer the taste. If you give it a try, let me know what you think.
Kelly Rose says
I just made this syrup and tried it out last night. I quite like it, but several of my friends find it too sour. I will probably try it again with half the citric acid and see what happens.
You mention that the citric acid helps with the extraction and also with preservation; how did you decide on quantity? Think it'll be ok to use half? Sugar is also a preservative, so if you start with a sterile jar, I'd expect the syrup to keep quite well. I'm pretty experienced with making and keeping different beverage syrups, and they usually keep for several months so long as you keep your container clean.
Hi Kelly - the amount of citric acid comes from several attempts at the recipe and finding the one that fits our tastes. I'd be more inclined to up the amount of simple syrup than to reduce the amount of citric acid - but, play with the recipe until it fits you. 😉 Cheers!
Have you tried Anchor Distillery's Junipero? It is, to me, the definitive gin. your tonic syrup recipe is fantastic.
Hi Brandon - no, I haven't. Thanks for the tip! And so glad you like the tonic..Cheers!
Oh Marissa...this stuff is heaven! I've been making a version of this for the last six months and I must say it makes the best G&T ever! I do like the bitter flavor profile of the cinchona so I use just a bit more and steep it in hot water (not boiling) to make a "tea" to extract the full flavor of it. Then I let it cool completely before adding the citric acid and the rest of the botanicals - I totally agree with the cold extract approach for the delicate parts!
Christopher, thank you so much!! It's so great of you to come by to let me know. Cheers!!
Did anyone find that theirs was was a bit bitter from the citrus? I know I followed the recipe exactly but it really made us pucker last night.
Hi Joslyn - Honestly, I like a bit of pucker. I suggest more simple syrup to balance the flavor to your taste. Cheers!
Alyssa Janco says
Hi Marissa! Being a new food blogger, everything about your website and take on food inspires me. But especially this recipe! Do you have any idea how long it will be good for?
Hi Alyssa, and thank you! 😉 That's a great question and I'm sorry that I don't have an exact answer. The citric acid helps to preserve the tonic and adding a splash or two of Vodka should make it last even longer.
I am about to make some tonic based on your recipe but I have cinchona powder and I was wondering how much to put in? I know cinchona can be dangerous if you use too much!
That's a great question - here are a couple of online resources for buying cinchona that I'm sure could answer that more accurately than I can, http://www.milfordspice.com/ & http://www.tenzingmomo.com/
Thanks for your recipe! I just made a batch and am "testing" it even now.
The aromatics are amazing - I made a control G&T with Fever Tree and there's no comparison. For my taste, though, the syrup is too sour (I assume I'm tasting the citric acid). I added about a teaspoon of 2:1 simple syrup to my drink, and that was (to me) a big improvement.
To the folks asking about how long it keeps - I would suggest adding a splash of vodka (I added about 1/2 oz to the total quart-plus). I've been doing this with homemade grenadine (based on Jeffrey Morgenthaler's recipe) and it keeps for months. I would expect the tonic syrup, with the citric acid, to keep at least as long.
Hi Stewart. I'm so glad you enjoyed the recipe and that you've made it your own with a bit of added sweetness. Good note on the splash of vodka. Cheers!
I stumbled across your website in the search of gift ideas for my partner.
He is a Gin fanatic and has already been making his own tonic syrup but is just adding to store bought soda water. I wondered whether you make your own soda and whether you have done any comparisons/testing in relation to it??
Like for example do you know if the Soda Stream soda water is any good or any better than store bought. Or if there are other ways you would recommend making your own soda??
I had also seen the Perlini shaker but a friend who works in cocktails didn't really say it was that great.
Any advice would be appreciated. I see that Soda Stream has a version that has glass bottles which I much prefer. Don't like the PET ones they have on the cheaper machines.
This is such a great question! My short answer (for our taste anyway) is, the more bubbly the better. We've tried many kinds and have settled on Talking Rain brand. I agree with you about glass vs. PET and I think a Soda Stream would probably work great! If you go that route, will you let me know how it is?
So, I ended up purchasing a soda syphon. (http://www.kitchenwarehouse.com.au/D-Line-Mesh-Soda-Syphon) as I just wasn't happy with the soda stream idea. I love the old school look of these also.
Will keep you updated on how it goes - his birthday is not until 25th Nov, so will be sometime after then! 😉