Did you know that tonic water glows? Because I sure didn’t!
The quinine content in tonic water glows when exposed to ultraviolet light. You may even be able to see the molecules glow in direct sunlight when placed against a dark background.
How cool is that? I didn’t need another reason to love tonic water, but lo and behold!
For fans of cocktails, tonic water is probably a staple in your kitchen. But, in case you’re new to the game, welcome to the world of tonic water!
Read on for our in-depth take on my beverage of choice, its expiration date, how to best store it, plus some fun recipes for the road.
Cocktails await!
What We Discovered

Tonic water can’t really go bad, since it’s mostly water.
So, even if it’s flat and lifeless and sad tasting, it’s still usually safe to drink, though it could be rather unenjoyable in this state.
That being said, contaminants can sneak into that bottle, thereby rendering it unsafe to drink.
So, as a general rule of thumb, it’s best to toss any flat tonic water you may have and crack open a new bottle.
What Exactly is Tonic Water?

Tonic water was initially created to treat and prevent malaria.
Wild, huh?
Way back when, the indigenous peoples of Western South America used the bark of the cinchona trees to prevent disease. When the colonizers came along and learned of this medicinal bark, they immediately started harvesting it for their own use.
Quinine, the main flavor in tonic water, is the derivative of the cinchona bark.
However, the bitter taste of quinine was off-putting, so they combined it with soda and sugar to make it more palatable.
The beloved gin and tonic came to be in British colonial India, where they were also searching for ways to make quinine easier to sip on.

Nowadays, the quinine content in tonic water is far less, so the bitter taste is less prevalent.
Most tonic waters are a combination of quinine, sugar (or high fructose corn syrup), carbonated water, citric acid, and occasionally preservatives like sodium benzoate or potassium sorbate.
Some of the fancier brands out there will add botanicals to elevate the flavor profile, such as juniper berries, kaffir, or bitter orange.
Of course, tonic water does more than create beautiful cocktails or treat malaria. It can also be used to aid digestion, as a stain remover, or to remove rust.
As for all the other carbonated beverages out there, here’s a quick guide for you.
Quick Guide to Carbonated Water

Seltzer water is artificially carbonated, like tonic water, but without quinine or added flavoring.
Carbonated water has naturally-occurring carbon dioxide with lots of minerals.
Club soda is essentially seltzer water with salt!
How to Store Tonic Water

Tonic water is very easy to store!
When unopened, store it in a dry and dark spot. Sunshine and heat aren’t its friends, so avoid those if possible.
If you’ve got a pantry or a liquor cabinet, that’s the perfect spot for it.
If opened, it will only last 1-2 days out at room temperature. However, if it’s still sealed and unopened, those bottles can last for months, sometimes even a year or more!
Storing it in the fridge once opened is necessary as it helps the flavor stick around, as well as the carbonation! But don’t stick an open bottle back in the fridge.
Resealing it keeps the carbonation trapped inside. If it’s in an open can, pour it into a different sealable bottle and store it in that instead.
How to Tell if Your Tonic Water Has Expired
When checking to see if your tonic water is still safe to drink, it’s best to use your senses and trust your gut. Here are some signs to watch out for:
Odor
Discoloration
Flatness
Dented Bottle or Can
Most tonic water has a very light aroma, so when it’s very strong, you know it’s on its way out of town.
As for discoloration, look for a slight yellowish tint. That’s a sure sign that your tonic water is best poured down the sink.
If you open a bottle of tonic water to find it flat, please don’t drink it. Left-out tonic water will go flat, but could still be safe to drink, so please proceed with caution!
Finally, dented or misshapen containers could be an indicator of botulism, which we’d all like to avoid.
And, if you’re still not sure, check that expiration date. If it expired over a year ago, let it go.
How to Use Tonic Water

I love using tonic water in cocktails (or mocktails, depending on the night)!
It always adds a slightly sweet, slightly bitter flavor to whatever I’m drinking.
The most classic use of tonic water is in the ever-delicious gin and tonic.
The ingredients are simple: tonic water, gin, lime, and a nice hunk of ice. For the holiday season, consider adding in some cranberry juice for a refreshing twist! You could also swap the gin out for vodka, if you prefer.
If you’re feeling funky, you could always try an espresso and tonic! This drink is particularly popular in Europe, though it's gaining traction in the States as well.
After brewing two shots of espresso, leave it to cool. Then, fill a cup with ice and squeeze some lime juice on top. Pour in your tonic water and finally the espresso. Afternoon perk-me-up for the win!
Some people love sipping on tonic water as you would with any other carbonated beverage. It’s just as refreshing as seltzer, but far more interesting for the tastebuds.
FAQs
Can you freeze tonic water?
You can, but you probably don’t want to.
Freezing tonic water eliminates all the carbonation, making it extremely flat and dull once thawed.
Besides, tonic water has such a long shelf life that there’s really no point in freezing it in the first place. As long as you put it in the fridge once it’s opened, you should be just fine.
Is it okay to drink expired tonic water?
It’s okay to drink flat tonic water, but if it’s discolored or has an unpleasant odor, it’s best to stay away.
Drinking or consuming anything that’s spoiled or expired often comes with painful and unpleasant consequences, so why risk it?
My general rule of thumb for tonic water is as follows: if it expired over a year ago, it’s time to let it go.
Does canned tonic water expire faster than bottled tonic water?
Not necessarily. Since canned tonic water is not resealable, there’s a chance it will go bad faster, unless you transfer it to a sealable container.
However, if it’s still sealed and unopened, both canned and bottled tonic water should last about the same amount of time.
Conclusion
There’s nothing better than a refreshing gin and tonic after a hot summer’s day.
So, before you whip up your next drink, check your tonic water’s expiration date and look for signs of spoilage.
But remember: tonic water doesn’t go bad quickly. If it expired over a year ago, it’s time to let it go, but a couple of months should be fine.
Happy drinking!
Dolly