This Viral Hack To Keep 2-Liter Soda Fizzy Doesn't Really Work — Here's The Science

Buying a two-liter bottle of soda usually makes financial sense — you get more for your money than if you were purchasing a pack of canned soda. That said, it can be tough to get through a two-liter before your soda goes flat, and there's a viral social media trick that claims to keep soda fizzy longer. TikTok users are sharing videos of themselves squeezing the air out of soda bottles and recapping them in an attempt to retain carbonation. Ed McCormick, the CEO of Cape Crystal Brands, spoke exclusively with Chowhound to inform us whether this trick is worth trying.

"The bottom line is that the TikTok hack is not entirely untrue, but it is well exaggerated," McCormick said. "It is kind of helpful, but not very much of a payback based on the effort needed to implement that soda hack strategy." He explained how the supposed hack works. Pushing air out of the bottle by squeezing it before replacing the cap reduces the headspace in the bottle, which is the amount of air above the liquid.

"This is temporarily decreasing the amount of carbon dioxide that can escape from the soda and into that space," said McCormick. While the hack could make sense, opening the bottle depressurizes it in the first place. Even though it might slow the rate at which the soda loses its fizz, our expert said, "It does not reverse the process by which soda becomes flat."

If you've got a fresh two-liter in your fridge and you think carbonated drinks taste better than non-carbonated options, you want it to stay fizzy for as long as possible after opening. Usually, it takes two or three days for opened soda to go totally flat, but Ed McCormick shared a few tips with us to help you keep your soda fizzy for as long as possible. First, he recommends popping the bottle back in the fridge immediately after you pour your first glass. While pressure puts carbon dioxide into soda, it becomes more soluble in liquid at lower temperatures.

You'll also want to open the bottle sparingly — it might make sense to pour yourself a large glass rather than repeatedly refilling a small cup. Keeping the bottle as stable as you can is also key. Shaking or moving the bottle excessively can cause the fizz to dissipate (if you prefer your soda without fizz, you can use a milk frother to take soda from fizzy to flat). If you don't want to buy a pack of cans but prefer super-fizzy soda, McCormick suggests finding the happy medium — one-liter bottles can be a good fit. "Smaller containers will remain carbonated longer, simply because they are opened less often," he said.