Hello, Friends of Cocktails! Today I'll explain how mixing baking soda with acidic ingredients - like citrus or vinegar - can change the pH level of your drinks, making for better cocktails! In fact, we’ll make two: a Gin Old Fashioned with balsamic syrup, and a Baking Whiskey Sour with an improved orange shrub. Who said the simple baking soda and vinegar experiment could be the secret to taking your cocktails to the next level?
We’ll also get into the chemistry behind this interesting technique when we reach the Bottom of The Glass, but first let’s where this idea came from. This technique is called Reverse Acidity by its creator, Liberty Adams. He’s a bar manager at Takibi, a Japanese bar and restaurant in Portland, Oregon, and it was named one of Esquire’s Top 25 Bars in the US in 2022.
Takibi is currently closed for repairs following a small fire, but Liberty reached out to share a technique he was working on when trying to clarify coffee, of all things. He didn’t want to add citrus to his coffee, so he used vinegar and milk to clarify it like that. But that of course resulted in an acidic cocktail, which he wasn’t happy with - and yes, he also tried the powdered milk technique that we covered recently, but he found it a bit finicky, so he experimented on.
Finally he added sodium bicarbonate, or baking soda, into the coffee-vinegar-milk mixture. That brought down the acidity level in the liquid, but still separated the buttery whey. He called the resulting drink the Butter Bean Coffee, but something else caught my attention - how this technique can be used to incorporate vinegar flavors into cocktails without the strong bite of acetic acid that can overpower a cocktail.
Liberty Adams was thinking the same thing as he already created a Gin cocktail with Balsamic Syrup, but we’ll also make an Improved Orange Shrub for a wonderful Orange Whiskey Sour. Let’s start with Balsamic Syrup that we’ll use to make the cocktail Liberty Adams calls the Reverse Engineer. It’s Cocktail Time!
Balsamic Syrup
● 120mL · 4oz Balsamic Vinegar
● 8g Baking Soda
● 62.4g Sugar
I’ll start by adding the balsamic vinegar into a large measuring beaker to have plenty of room for the chemical reaction later. For the vinegar, find the highest quality you can to make the best syrup for your cocktail, and look for one with a 6% acidity. I’ll also be using a magnetic stirrer, a pH meter and a refractometer, which are optional but linked if you want to geek out!
This vinegar has a pH level of 2.45, which is slightly above lemon juice and below apple juice, which we’ll increase by adding the baking soda. I’m doing this in two parts,but if you have a smaller cup start with less. The reaction will be instant, with foamy bubbles rising from our mixture, but we’ll end up with a diluted acetic acid solution, meaning it will have a higher pH overall. Once the bubbles and the foam die down I’ll check the pH level, just to see where we’re at, which for me was 5.28, which is similar to black coffee or bananas, meaning the acetic acid will be much less pronounced.
More importantly though, we need to know how much sugar we’ll need to make this into a 1:1 syrup. For that we need to know the weight and the BRIX level - for us that was 130g at 26 BRIX. I’ll add these values into the Flavored Syrup calculator, which will tell us how much sugar is needed to get to 50 BRIX, which is the sweetness level of a simple syrup.
I got 62.4 grams, and if you followed along with the recipe you can do the same. Now stir until dissolved and you’ve got yourself a Balsamic Syrup that you can pour it into a bottle, label it and keep it in the fridge. Before I show you how to make the Improved Orange Shrub, let’s first make and try the Reverse Engineer with our Balsamic Syrup.
Reverse Engineer
● 60mL · 2oz Ki No Bi Gin
● 7.5mL · 0.25oz Balsamic Syrup
● 3 dashes Aromatic Bitters
● 2 dashes Orange Bitters
Start with a well chilled tumbler glass and a large ice cube that’s already been tempered, then pour your ingredients over it. It’s not often you see gin being used in an Old Fashioned-styled cocktail, but according to Liberty Adams, the balsamic vinegar adds caramel and woody notes, but also no, no saline solution this time since there’s salt in the vinegar. Then stir to chill and dilute, and for garnish take a small circle of orange peel, express the essential oils and place the peel on the ice. Cheers!
The appearance is dark, but the cocktail’s aroma reveals sweet balsamic and orange notes. When I tested this at home and my wife tried it she said it's more like a Negroni than an Old Fashioned, which I completely agree with. Gin and the grape-based balsamic vinegar give it botanical and even subtly aged, sherry-like oxidized notes, alongside the bitter-sweet balance. So it ticks all the boxes for a Negroni, which is a compliment for any cocktail, if you ask me. So great job, Liberty, and cheers!
With the syrup done, let’s take a look at how we can make an improved shrub, one that uses the vinegar’s acid to pull flavors from an ingredient like an orange. The only difference to traditional shrubs is that we’re then able to minimize the harshness of the acetic acid, and even replace it with another acid, like citric, malic, lactic - whatever fits your shrub’s flavor profile.
Improved Orange Shrub
● 36g Orange Peels
● 200g Sugar
● 200g Orange Juice
● 3.44g Baking Soda
● 7.14g Malic Acid
● 14.32g Citric Acid
● 150mL · 5oz White Balsamic Vinegar
We’ll need ro cover the orange peels with sugar, give the mixture a muddle and leave it to sit for 1-2 hours for the sugar to start pulling the essential oils from the peels and soften them in the process. As always when using the peels of a citrus, make sure the peels are safe to consume, as highlighted in our Dangerous Ingredients episode.
After two hours juice enough oranges to get the 200g of orange juice and measure out the white balsamic vinegar, a milder, less caramelized version of traditional balsamic vinegar. Then add the orange peels and the sugar and blend on high speed for at least 30 seconds for everything to blend and mix. Now strain through a cloth filter to remove the solids and we’ll measure the pH of our liquid to know where we’re at.
This time it sits at a pH of 3, which is already up from the 2.5 we started with from the white balsamic vinegar. So just as before, make sure you’re using a tall beaker to contain the reaction in and add in the baking soda. This way we’re aiming for a pH level of 4, since we still want a little of that acetic acidity - it’s a shrub after all. I added everything at once, but you can do it in smaller sections if you don't have a large enough glass.
Same as before, once everything settles down I’m checking the pH levels and we’re right at 4, but as far as shrubs go you want them to balance the sweetness as well, so let’s add citric and malic acid. Once that’s completely mixed I’ll check the pH level one last time, and we’re on 2.2 which is comparable to a lemon and lime, so we’re done. Bottle, label, and let’s make the Baking Whiskey Sour.
Baking Whiskey Sour
● 60mL · 2oz Bourbon
● 15mL · 0.5oz Improved Orange Shrub
● 15mL · 0.5oz Super Foam
● 7.5mL · 0.25oz Lemon Super Juice
● 7.5mL · 0.25oz Gum Syrup
As I always do, ice in the big tin, ingredients in the small shaker tin. We’ll do a reverse dry shake, so once you shake it once, drain the ice, then add the cocktail and shake vigorously again to really enhance the frothiness and silkiness of our Baking Whiskey Sour. Strain through a fine mesh strainer into a low tumbler glass filled with ice cubes. Garnish with a cocktail cherry this time and enjoy, cheers!
It’s sweet, silky, citrusy and rich, with orange flavor coming to the front, but without that extra sweetness of orange juice. Shrub adds richness and nicely brings the flavors together, so I’m definitely calling this a successful experiment. I’m honored Liberty Adams reached out so I could be one of the first to try this interesting technique, and it’ll be fun to see where it goes - milk punches without acidity or unique sodas, the sky's the limit.
With that you’ve reached the Bottom of The Glass and we’re taking a chemistry lesson. So, what exactly happens when you mix vinegar and baking soda? Well the equation is NaHCO3 + HC2H3O2→ NaC2H3O2 + H2O + CO2. So sodium bicarbonate plus acetic acid produce carbonic acid and sodium acetate, which then begin to decompose and form carbon dioxide gas and water, causing foamy bubbles as the CO2 is heavier than the air around it.
What results from the reaction is a diluted acetic acid solution, which is what we used for our cocktails. Interestingly, in baking, this works as a leavening agent to help your baked goods rise, so once again the gastronomy and mixology worlds collide. To see me collaborate with an excellent chef, check out this post and see you next week. Cheers!