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It was a warm, sunny Sunday afternoon in Boulder, Colorado, and I wanted two things: a hammock in the shade and ice cream.
But there was a catch. Any bum can laze away a day in the backyard; I wanted those hallmarks of summer in a killer creekside spot tucked away in quiet woods.
Challenge accepted. I didn’t have a cooler small enough to transport on my bike, and surely the ice cream would melt in the 80°F weather if I scooped it into plasticware. Any connoisseur knows that melted ice cream, while delicious, is the lesser form of the stuff. I wanted freezer-quality ice cream.
I looked around my kitchen. I own enough reusable travel mugs to effectively cancel out their eco cred. They all claim to keep contents cold for hours or even days. I grabbed a Stanley insulated mug and hoped for the best.
My boyfriend, Nick, told me flatly that it wouldn’t work. But so what if I ended up with a mug full of soupy, sweet milk? I have bigger failures on my résumé.
I packed the 12-ounce bottle with mint chocolate chip, screwed the lid on tight, and tossed it into a pack. Nick and I headed off on bikes, and 40 minutes later, I hung a hammock in the shade, practically arm’s length from a shallow spot in the creek that looked perfect for wading. But the water could wait. I climbed into the hammock and opened my mug, fully expecting to drink my dessert.
But it was perfect, cold and firm just like ice cream is supposed to be. It was like it had never even left the freezer, and I only had to glance at Nick to convey an “I told you so” even sweeter than the mint chip. (I shared some with him, anyway.)
I enjoyed the victory, but was more excited by its implications. Hot days, long days, beach days . . . what kind of day isn’t improved
by ice cream?
Clearly, I needed to do more research to extend my frosty reach. My counter became a test lab for all shapes and sizes of insulated bottles. Big ones, tall ones, short ones, skinny ones. Bottles made for drinking hot coffee and insulated pint containers intended for beer. I packed them full of ice cream and set them on my kitchen counter in the morning, then checked to see how well they’d performed when I got home from work at night.
I was eating ice cream for science. I was living the life.
Around the time I purchased my fourth or fifth (but let’s say fourth) carton of science ice cream, it became clear that I was doing a lot of dessert eating and not enough hiking. I wondered: Could my portable, ultralight freezer hold out during an overnight trek?
In August, I set out for a 19-mile out-and-back to a natural hot spring near Aspen. If I could serve ice cream on a backpacking trip, I would have nothing left to prove. I stashed an 18-ounce, steel Stanley Master Vacuum Mug in the freezer the night before (pre-chilling the bottle is a key trick I’d learned). The bottle was a little heavier than I’d have liked at 1.1 pounds, but it had proven the most reliable during the summer’s experiments. In the morning, I packed the Stanley as tightly as possible—densely packed ice cream stays cold better and goes farther—with chocolate chip cookie dough and a layer of mint moosetracks on top.
After a three-hour drive to the trailhead, we trekked through aspen groves, across a river, and stopped for breaks in the shade.
The cloudless August day was hot. It took all of my willpower to not crack open the bottle to check its contents every time someone stopped to
tie a boot.
Just before dark, we snagged one of the last campsites within view of the hot spring. After dinner—a full 12 hours after we left our freezer behind—I opened the tall, narrow bottle. The mint moosetracks looked a little soupy at the top, and my spoon hit soft-serve consistency a bit deeper. I groaned. Had I found the limit? But then I dug further into the chocolate chip cookie dough, about halfway down.
So solid it nearly bent my titanium spoon.
More than 250 miles from the freezer, almost 10 miles from the trailhead, ice cream was served.
After we ate our fill—amazingly, we didn’t finish it—I sealed the bottle and stowed it with our bear canister. Later, while soaking in the hot spring, I wondered if the nighttime lows in the 40s would be cold enough to help preserve the leftovers.
In the morning, we packed up camp and headed out. We stopped
for a mid-morning snack about halfway to the trailhead. Hungry, hot,
and sweaty, we rested in the shade by the river and pulled out the ice cream. Still frozen.
Victory never tasted so good.
The Verdict: Pass
Through experimentation and, well, gluttony, I learned how to have ice cream in the backcountry—more than 24 hours after taking it from the freezer.
Put your empty, open bottle in the freezer overnight before filling it with ice cream. Some bottles may warn against this, but the brands just don’t want you to freeze liquid inside the bottle, which can cause bulging that compromises the vacuum seal.
Ice cream flavors with lower sugar and fat contents will generally freeze harder than flavors with more sugar and fat.
Lighter-weight bottles with less insulation work well for a few hours. For a short trip, I liked Stanley’s compact, 8-ounce Adventure Vacuum Mug and the 17-ounce Avex ReCharge Autoseal Travel Mug. MiiR and Hydro Flask both have wide-mouthed containers ideal for scooping. For a longer day, hotter weather, or an overnight trip, Stanley’s Master Vacuum Mug is the best choice.