SuChin Pak is very passionate about bubbles. In particular, she likes a drink with bubbles that are tiny and tight, going so far as to create her own sparkling beverage mixtures to ensure the highest bubble density possible. Her favorite? Guayakí Yerba Mate Sparkling Grapefruit Ginger cut with a plain seltzer water to infuse more fizz or Gerolsteiner if she’s opting for something flavorless.
“I don’t want a loose bubble,” she said on an episode of her podcast, Add to Cart, back in November 2020. “I want it tight. I want to when you open it up, and you get that first sip, it just tickles your tongue. Like little tiny elves dancing on the tip of your tongue.”
A tight bubble. I haven’t been able to shake the idea ever since. As a longtime sparkling water drinker, I often tried to parse out why I preferred certain brands over others. And now, I finally have a metric. Bubble tightness.
Over the last year every time I would try a new sparkling water, I’d carefully examine the sip, turning it over on my tongue like some kind of carbonation sommelier. With more consideration, more questions arose, and in an existential fit I found myself screaming into a void, “Why do we even like sparkling water at all?!” When the void didn’t respond, I sought answers elsewhere, specifically with a certified food scientist and the queen of bubbles herself, SuChin Pak.
The chemistry of sparkling water is very simple. It’s essentially two compounds, good ole fashioned H2O, which even in bubbly form keeps us hydrated, and carbon dioxide, which is of course the bubbly element. It turns out that the reason we enjoy carbonation is similar to the reason we enjoy hot sauce: we love pain. Dr. Helene Hopfer, an assistant professor of food science at Penn State with a focus in sensory analysis, describes it to me very technically.
“CO2 is an activator of TRPV1, the trigeminal receptors; it’s a pain receptor that gets activated by the carbonic acid,” she says. “If you have a very young child or if you give sparkling water to a young child, they might have a very adverse reaction to it—they might not like it because it hurts. They haven’t learned to like the pain yet.”
Pak has seen firsthand the reaction from a less experienced palate with her own kids, who call her sparkling drinks “spicy water.” Alcohol provides a similar effect, so when you’re downing a carbonated White Claw or a sparkling wine you’re actually just stimulating the pain sensors in your tongue even further.
Pak, who doesn’t indulge in alcohol or coffee, drinks sparkling water just to feel something. “I’m always trying to find a way to consume a beverage that gives me a little bit of a lift, and the carbonation just does that right away,” Pak says. “That pain kind of wakes you up.”
Carbonation isn’t just lighting up our taste buds, it floats up our nose (where we also have those pain receptors), it whispers into our ears, it looks like tiny dancing gems, and a particularly bubbly concoction might even result in a mini ocean spray on your skin. In short: sparkling water offers a full sensory experience.
So what factors are at play to make one sparkling water better than another? Dr. Hopfer says that packaging is extremely important. “[Carbonation] needs a nucleation site, so you need to have some imperfection in the glass you pour it in or the can that you have that allows those bubbles to form,” she says. “In a lab you might be able to create a complete smooth surface, and in that case you wouldn’t get any bubble formation.”
This perhaps is why in the great bubble density wars, Topo Chico comes out on top, both because of tiny crevices etched into the glass bottle design and the changing shape at the bottle’s neck allowing the bubbles to really rev up right before they hit your lips.
Those who appreciate a more bubble-forward drink are also likely to go with something more plain. This doesn’t necessarily have to do with the actual chemistry of the beverage, but what our brain perceives, says Dr. Hopfer. For example, in a heavily flavored water like a Spindrift, the introduction of additional elements, including strong, often sweet tastes, distracts the brain from focusing on just the fizz, making us think that the bubble density has decreased even if it physically is exactly the same as a Topo Chico’s bubbles.
But not all things can be explained. My new favorite seltzer somehow has peak bubble sharpness and flavor, all in an aluminum can: PurAqua Belle Vie Cherry Lime. Even with all the science in the world, sometimes it just comes down to a personal taste test.
As a child in the ’90s, when I saw someone drinking sparkling water I assumed they were the fanciest person alive. And that sociological appeal still rings true. When I asked Dr. Hopfer about the connection, she said that while there’s no explicit research on this, seltzer’s association with “high-end” drinks like champagne (though we all know there are some perfectly fine cheap champagne options out there) may also have an impact on the rising popularity of these now extremely common and mostly very affordable beverages.
“There is also this idea that you have to learn to like it, so it is perceived as a more adult thing,” Dr. Hopfer says. “Historically the presence of bubbles might have been associated with something that is more rare and less available and more unique and more exclusive.”
These days, it does seem that everyone drinks some kind of carbonated water as the market continues to expand. But according to Pak, there is still a specific profile of those who are more passionate about their bubbly drinks than others.
“I think a sparkling beverage consumer is someone who likes to have fun but is very clear about boundaries,” Pak says. “A little goes a long way, and if you want more, fine. They’re not on cleanses and restrictive diets, they can still hang and party with you, but they’re the designated driver, they’re watching your purse in the club so you can dance.”
If that’s not a reason to join #TeamTightBubble, I don’t know what is.