Dry ice is a cool way to chill

Imagine. Icy cold popsicles at the beach.

Or rock-solid ice cream.

Or sushi at sunset.

It's all possible with dry ice, the frozen form of carbon dioxide. Sure, it's the same stuff that fills witches' cauldrons with eerie fog at Halloween. Dry ice is also handy for removing dents from cars, branding cattle and eradicating gophers.

But placing a solid block of minus-109-degree dry ice inside your beach or boat cooler can keep food frozen for 18 hours or more and the rest of your foodstuff cool and dry.

In addition, dry ice doesn't melt like ice. It sublimates, skipping the messy liquid stage and turning directly from solid to gas. That means a very cool, bone-dry cooler.

Dry ice "is a little more expensive, but you can keep things colder a lot longer," said Ellen

Ackerman, who has been in the dry ice business for decades and is president of the California-based dryiceInfo.com.

Locally, dry ice is available in some grocery stores, including most Krogers, where it is 99 cents a pound. It runs five times the price of regular ice or more, but we found it well worth the expense.

Using dry ice requires caution. Direct contact can cause your skin to freeze, a painful injury similar to a burn. It can be handled only with gloves or towels, or while it's wrapped in a barrier like newspapers or paper bags. It should be kept out of children's reach.

Dry ice can't be stored in an airtight container because the CO2 gas needs room to expand. When transporting dry ice in a car, for example, a window must be kept cracked. Breathing air heavy with CO2 can restrict oxygen intake.

To even buy dry ice at Kroger, you have to be 21.

Undeterred by the dangers, we bought a bag from a Virginia Beach Kroger on a recent beach day. The 9-pound block came in a loose plastic bag with a few slits for ventilation and extra plastic at the top that made it easy to lift out of the cooler without getting, er, burned.

Ackerman suggested having the bagger wrap the dry ice in a paper grocery sack. That acts as an insulator, she said. The more dry ice is insulated, the longer it lasts.

There are different schools of thought on how best to pack a cooler with dry ice. Should the ice go on the top? On the bottom? In the middle?

We opted for the bottom of the cooler, where we'd have less reason to move it around. We set the lid of an old Styrofoam cooler on top of the ice block. Then in went a dozen popsicles - frozen food should be as close to the dry ice as possible but not directly touching. In went a few sodas, sandwiches wrapped in waxed paper, some apples, Gatorade and crackers still in the cardboard box. Then we stuffed the rest of the space with pretty pink beach towels.

For ventilation, we pulled the drain plug, although Ackerman said that was not necessary because the seal on most recreational coolers allows enough air exchange.

A few hours later at the beach, we wanted a popsicle. They were frozen solid, and the sodas were icy cold. Nothing was soggy.

Back from the beach, we left the cooler in the un-air-conditioned garage with the popsicles and a few sodas. It wasn't until the third morning that the ice was gone and the popsicles were melted. The cooler was still dry, and simple to clean.

We'd always considered dry ice a bit dangerous; now we wouldn't pack for a day in the sun without it.

Lorraine Eaton, (757) 446-2697, lorraine.eaton@pilotonline.com