This backed-by-science party trick will save you from a meltdown (literally and figuratively)
One of my favorite summer activities as a kid was something called ice blocking. It was simple: Grab a giant block of ice, plop it on top of a grassy hill, cover it with a towel, then sit down and ride it like a sled until you skidded to the bottom—permanently grass-staining your shorts in the process. My buddies and I kept going until the ice melted or our shorts got too soggy. Sometimes we’d up the ante by seeing who could sit directly on the ice the longest. (I once won a free T-shirt for freezing my butt off. It was 100% worth it.)
My point: Ice is more versatile than people give it credit for. “Not all ice is created equal,” says Bryan Quoc Le, PhD, a food scientist and the author of 150 Food Science Questions Answered. “The best type of ice depends on what you are using it for. Different types of ice have different properties, especially when it comes to how fast they melt.” (He had no comment on the butt-freezing competition.)
And when it comes to barbecues, ice is mission-critical. Nothing tanks a summer cookout faster than warm soda, iffy potato salad or chicken that may have been marinating in salmonella along with the sauce. So what’s the right ice to use when the grill is hot and the cooler is working overtime? Spoiler: It’s not the bag of tiny cubes from the gas station, which, admit it, is what we’ve all been using.
Read on to find out which ice Le and Camper English, author of The Ice Book, say you should use instead—so your next barbecue stays cool in every sense of the word.
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What is the best type of ice for a barbecue?
It turns out that the best type of ice for a barbecue is also the best type of ice for sledding: block ice.
This isn’t just backyard wisdom—it’s history. “The original ice cubes were smaller blocks sawed off a huge ice block harvested from lakes,” English explains. Before refrigeration, those massive blocks were carefully packed in sawdust and tucked away in icehouses, where they could last for months … even through a sweltering summer.
So if block ice could keep 19th-century milk, meat and medicine safe without electricity, it’s more than up to the challenge of chilling your burgers and beer today.
Why is block ice the best for a barbecue?
Block ice is the gold standard for keeping things cold outdoors, English says. And it’s not just vibes; there’s science to back up this choice.
It keeps your food cold for longer
Small cubes are basically ice sprinters—fast, efficient and done in record time. They cool faster, but they also melt faster. On the other hand, block ice is a marathoner: steady, chill and still going strong on hour four.
This is due to surface area. “The larger the ice, the smaller the surface area relative to its volume,” Le explains. “This means block ice melts much more slowly than cubes or crushed ice, so it keeps cooling for longer.”
It keeps your food from getting soggy
Small ice cubes mean well, but they make a mess—melting quickly, turning buns into sponges and leaving your cooler looking like a kiddie pool for grapes. “The smaller the cube, the more surface area is exposed, and the faster it melts,” Le says. “That’s why restaurants use crushed ice in fountain drinks—it chills liquid quickly.”
That same physics works against you when you’re trying to keep your cooler extra chill. But block ice, which stays intact longer, produces less puddle as the day goes on, English says. The end result—meltwater—is inevitable no matter the shape, but block ice delays the flood, giving you hours of extra chill. So your hot dog stays a hot dog, not a dunk-tank casualty.
It gives your food an (n)ice foundation
One of our experts’ top tips for the best way to pack a cooler is to put a layer of ice underneath the food and on top, creating an ice sandwich. A flat block of ice creates a nice bottom layer. It may take up a little more room (as it can’t fill in the gaps between food like small cubes can), but it’s worth it for the extra chill power.
It’s reusable (sort of)
OK, not forever—but block ice holds up so well that you can sometimes refreeze what’s left to put in your cooler the next day. Or repurpose it by letting the kids ride it down the nearest hill! (Don’t knock it till you’ve tried it!)
Is there a way to get it to last even longer?
Yes. Here’s your nerdy-but-cool party trick: Sprinkle rock salt on your block ice right after placing it in the cooler. “Adding salt lowers the freezing point of water,” says Le. That means it can get the cooler down below 32 degrees Fahrenheit, which keeps foods colder and safer for longer.
This may seem counterintuitive since we use salt to melt ice in the winter, but it turns out that sprinkling salt on ice makes the sidewalks less slippery by actually making the ice colder. It’s due to a process called freezing point depression. The salt lowers the freezing point of water, so the ice has to melt a little to dissolve it. That melting process sucks up heat from the surroundings, which drops the temperature even further. It’s the same trick used in old-fashioned ice cream makers, and it can get your cooler chilly enough to keep dairy, meat and drinks frosty for hours.
Bonus: You can use this little science factoid to wow the kids (and slightly tipsy adults) at the barbecue.
Where can you buy block ice?
Good news: You don’t have to time-travel and steal it from a 1920s meat locker. Lots of grocery stores, liquor stores and gas stations carry block ice—you just have to ask. (It’s often hiding behind the bags of cubes.)
Or DIY it: Fill a rectangular plastic container or a mixing bowl with water, and freeze it. Voila! Homemade block ice. You get bragging rights and an excuse to use the word voila.
What are good alternatives to block ice?
Try freezing bottled water or drinks. They serve a dual purpose: They’re a large block of ice that melts slowly, and once the liquid thaws, you’ve got a perfectly cold drink.
Another good alternative is to put a smaller ice pack on the bottom of the cooler and layer crushed ice over the top. The ice pack will act as a foundational cooling element, helping to extend the life of the cubes. This way, you get the best of both worlds—long-lasting cold, plus easy scooping for drinks. (Although if you’re using this trick for a drink cooler, make sure you’re not making this common gross mistake at the barbecue.)
If you can’t find a block of ice, what’s the next best thing?
Any ice—or honestly, any frozen item—will do the job in a pinch, English says. Ice pops, bags of peas, even a rock-hard tub of ice cream can double as cooler fuel. (Just be warned: Nobody wants to reach in for a soda and come out with your back-of-the-freezer mystery Tupperware.)
And if you don’t have anything frozen? Chill drinks and food in the fridge overnight, then pack them tightly together in the cooler. Cold items help keep one another cold, kind of like penguins huddling for warmth—except, you know, the opposite.
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Sources:
- Bryan Quoc Le, PhD, food scientist, author of 150 Food Science Questions Answered and founder and principal food consultant at Mendocino Food Consulting; phone interview, Aug. 20, 2025
- Camper English, author of The Ice Book, founder of Alcademics and expert mixologist; email interview, Aug. 20, 2025
