Kerri WaldronOver the past year or so, we’ve truly witnessed a revival of Diet Coke — a renaissance, if you will. Fellow DC lovers (nope, not the comics) are probably familiar with the social media craze and even “recipes” for elevating everyone’s favorite afternoon pick-me-up. The peak really hit in 2023, when it became impossible to escape the videos of someone opening a can of crispy Diet Coke, dumping in a packet of crystallized lime juice, and stirring it around with a glass straw before taking that satisfying first sip.
Personally, I’ve always been a Coke Zero gal through and through (and you know what, I might still be), but the Diet Coke girlies definitely got to me. Before I knew it, cracking open a 2 p.m. Diet Coke in the office became somewhat of a ritual that I always looked forward to. Then, something tragic happened: Caffeinated sodas began disappearing from our fridge, and yes, that included my beloved Diet Coke.
Note that this is a total exaggeration and far from a tragedy. Our fridge gets stocked with plenty of sparkling water that we all love. I’m just overdramatic and under-caffeinated.
Claudia Santos
After simultaneously witnessing all the Diet Coke discourse on my feed and chatting with my coworkers about our mutual sadness over no longer having it, I realized that we all take this beverage very seriously. Specifically, people tend to have strong opinions when it comes to the different vessels Diet Coke comes in: bottles, cans, fountains, etc.
Cans tend to take over my feed, but I often hear people’s preference for McDonald’s Coke/Diet Coke in particular. So, as someone very interested in seemingly pointless data, I needed to know once and for all which one ranks supreme, and if any of us can even tell the difference between these.
So, with the incredible help of my coworker, Ross, we set out to conduct an office-wide blind taste test with four types of Diet Coke: a plastic bottle, a glass bottle, a can, and one from the McDonald’s fountain.
Each Diet Coke was assigned a number and then poured into three-ounce cups, which we labeled. Our testers were then asked to try the Diet Cokes one by one, guess which container it came in, and give a final ranking from their favorite to least favorite.
Here’s how each Diet Coke was assigned (not pictured: me trying to pour each one discretely):
1. Glass Bottle
2. Plastic Bottle
3. McDonald’s Fountain
4. Can
In total, we had 16 taste testers volunteer from the NYC office. When it came time for Ross and I to conduct the blind taste test for each other (because, of course, we wouldn’t pass up the opportunity to do this ourselves), we simply mixed up the order and noted down our personal rankings/guesses.
Ross Yoder
Before we dive into the results, we need to have a chat about McDonald’s. McDonald’s Diet Coke is usually seen as top-tier, and per their own website’s , this is because “The water and Coca-Cola syrup are pre-chilled before entering our fountain dispensers with the ratio of syrup set to allow for ice to melt.” Not going to lie; this kind of blew my mind. I always knew that McDonald’s made Coke the “traditional” way using syrups, but never knew they considered how ice would dilute the drink.
They also use filtered water and, of course, there’s the straw, which is “wider than a typical straw so all that Coke taste can hit your taste buds.”
With all that Diet Coke science in mind, we came up with a McDonald’s plan. First, order two large Diet Cokes with no ice (I messed this up the first time, oops). Second, dilute the Diet Coke with about one ounce of water to replicate the dilution from melted ice. Last, pour it into SodaStream bottles to prevent it from going flat.
Despite my mistake of ordering ice, I wasn’t carrying the Diet Coke long enough for it to melt, so I still stuck to the original plan of diluting it.
Claudia Santos
While the SodaStream bottles were meant to keep in the bubbles, we definitely ran into some issues. I picked up the sodas in the morning, and they immediately looked flat as I was pouring, so I had little hope for how they’d hold up. I also realized I definitely needed more. Now, worried that 1) we wouldn’t have enough Diet Coke and 2) our taste test would be thrown off by flat soda, I went to a different McDonald’s and grabbed two more. Again, they were flat.
We knew we’d lose some bubbles with this storage method, but being handed relatively flat soda from the start made it almost impossible to keep it fizzy.
Ross Yoder
During our taste test, we came to the conclusion that we couldn’t justify serving soda that was this flat. So, again, we grabbed two more Diet Cokes from yet another McDonald’s (Times Square is definitely not short on them). This location was a little more fizzy than the first two (and served to our remaining testers almost immediately), but it still didn’t seem to change people’s opinions on the McD’s Diet Coke.
For the record, I’ve had outstanding Diet Cokes at McDonald’s locations before, and so had many of our testers. In casually chatting with them, most of them even admitted to thinking that McDonald’s fountain would be the best option ahead of time. Lo and behold, I guess not all McDonald’s soda fountains are built the same.
Ross Yoder
Whew, what an emotional rollercoaster. With our McDonald’s fiasco finally settled, here is our official Diet Coke ranking from worst to best.
4. McDonald’s Fountain
This probably comes as a shock to no one, given our McDonald’s drama. But given we went to three different locations, and each one had some seriously lackluster fizz, this feels like a fair rating.
Ross Yoder
Not only did our testers have an issue with McDonald’s Diet Coke being flat, but they also found it to be overly sweet. One noted that they “could taste the fountain syrup,” and someone else thought that it could even be mistaken for regular Coke because of how sweet it was. We even had someone describe it as “bouba” (I won’t get into the , but it was probably the most accurate description I’d heard all day).
Okay, I’ll get a little into the kiki-bouba effect. Essentially, our brains associate the word “bouba” with a soft, round shape and the word “kiki” with a sharp, jagged shape. As with most things, the study made its way to social media, where people began describing sounds, sights, tastes, people, etc., as “bouba” or “kiki.”
Claudia Santos
The “syrupy” flavor was likely a dead giveaway since a majority of the testers accurately guessed that this was McDonald’s. However, the lack of fizz made many of us think this was one of the other three; no one expected McD’s to be the flattest of the bunch. If anything, we all thought it would have some of the best fizziness. Alas, we were left disappointed.
⭐️ OVERALL RATING: 1.5/5
3. Glass Bottle
This was gravely disappointing for me since Diet Coke in a glass bottle is the fun treat I get myself whenever I spot it. I personally ranked it as my favorite during my own taste test. Sadly, the numbers don’t lie, and the reviews were mixed.
Ross Yoder
A few of our testers thought it had that “classic” Diet Coke taste. Some thought the flavor was flat, and when it came to fizziness, they were split. Some found it to have a good fizz, while others thought it was flatter or even watered down. Personally, I found the fizziness to have a nice middle ground: It was fizzy without weirdly hurting your nose from being over-carbonated. But I definitely understand that it didn’t meet everyone’s bubbly Diet Coke expectations.
Funnily enough, half of our testers thought this was the plastic bottle. My guess is that plastic bottles are thought to be a little less fizzy, plus the glass bottle still had the “classic” taste most people expected. It’s also unsurprising, given that glass bottles aren’t always the easiest to find (petition to change this, please), so people are a little less familiar with the taste.
⭐️ OVERALL RATING: 3.2/5
2. Plastic Bottle
I know, I’m just as shocked as you are. Plastic bottles tend to get a lot of heat for being lower quality, but people really seemed to like it. The word “classic” was definitely thrown around with this one the most.
Ross Yoder
Most of the testers thought there was a nice level of fizziness and, again, a few recognized the classic Diet Coke flavor. One person described the flavor as “smooth and light,” and I’d have to agree. I definitely found it to have a lighter flavor than the others (especially McDonald’s…), although some people pointed out that it was a little sweet.
I was kind of surprised that only one person pointed out that this tasted plasticky! Even going into my taste test, I thought the plastic-like taste would be something I’d immediately recognize, but it wasn’t. I do think it’s likely something you’d notice more if you were drinking straight from the bottle.
Ross Yoder
Guesses were pretty split, but a majority still thought this was a glass bottle, even me. I think the “lighter” flavor combined with a decent level of fizziness fooled a lot of us into thinking it was in a higher-quality container. This, again, is pretty fascinating considering people would normally rank a plastic bottle at the bottom of their list.
⭐️ OVERALL RATING: 3.8/5
1. Can
The canned Diet Coke that’s all over our For You pages emerged victorious. Honestly, I’m not mad about it — you just can’t beat that satisfying sound of opening a crisp can. From flavor to fizziness, people loved this one.
Ross Yoder
“Main character energy,” “summery,” “crisp” — yeah, this was definitely a favorite. The fizziness from the can really smacks you in the face, and despite it having been in an open container that couldn’t be resealed between testers, it didn’t lose its fizz. Whereas McDonald’s was “bouba,” the canned Diet Coke was aptly described as “kiki.” I took one sip and immediately said, “Whoa, zig-zaggy.” And if none of those adjectives mean anything to you, think of it as the one you’d want to pour over ice with a little lime on a hot summer day.
Even though guesses were still relatively split, most people guessed this was the can. One tester literally took one sip and said, “Yup, that’s a can” — it was very impressive. This is likely what Diet Coke connoisseurs often reach for, especially since it’s what’s readily available in offices, restaurants, delis, planes, etc.
⭐️ OVERALL RATING: 4.4/5
So, yes, canned Diet Coke technically won, and was certainly tied with McDonald’s when it comes to ease of recognition. But (and this is a very big but), I’m hesitant to declare it as the supreme Diet Coke. With the exception of McDonald’s — where we clearly ran into some mishaps — there wasn’t a definitive consensus for each Diet Coke.
All in all, the main takeaway I got from this taste test was that whatever you choose to drink your Diet Coke out of is really personal preference. Case in point, I will always reach for a glass bottle over a can because I like a medium-level fizz plus crisp flavor.
And will I ever pass up a McDonald’s Diet Coke when I’m in the middle of a road trip and deserve a fun treat? Absolutely not.
Let us know which is your favorite Diet Coke in the comments! Or maybe there’s a secret fifth option we need to try next.
Source: bing.com
