On camping holidays, at music festivals or when the fridge is broken, you need to keep your beer cold.

How? Let’s ask the experts: Dr Karl Kruszelnicki, who’s just released his latest book, Dr Karl’s Short Back & Science, and Melbourne band Mighty Duke And The Lords, which is playing Meredith Music Festival (to which you can bring your own booze).

First up, hard-wall eskies or soft-wall eskies? For Kruszelnicki, this is a no-brainer. “The hard-wall eskies are better insulated than the softer ones,” he says. “The thicker the wall of the esky, the better.”

Moving along to the ratio of beer to ice, the good doctor says the tip is to keep your esky well stocked. “You want to have as many cans in there as possible, right from the beginning,” he says. “Restocking the esky with more beer that isn’t cold will drive your Esky temperature right up.” Buy your beer already chilled, or put it in the fridge the night before.

Do you ever see people tipping out the melted sloshy esky water to go and get more ice? Kruszelnicki says this is a rookie error. “Never throw out the water while it’s colder than the outside world. As long as you’ve got any amount of cool, hang on to it.”

If you’re keen to be hailed a frozen-ale legend, Kruszelnicki has a rather extreme beer-cooling idea that will cool your beer for days on end and has been tried and tested by the man himself. It involves two eskies and dry ice, and is potentially dangerous while camping, so let’s leave this one for another time.

A radical beer-cooling idea you can put to the test comes courtesy of the guys of Mighty Duke And The Lords. The band’s sound is described as a “tropical cyclone of mad calypso rhythm and rum-soaked tomfoolery”, so it’s a safe bet they know what they’re talking about.

“If you’ve got your car, once you get where you’re going, take the spare tyre out of the boot and line the space with plastic,” says Wally Maloney, aka Duke. “Then fill it with beer and ice and shut the lid, placing a decoy Esky on top. You can keep two slabs cold for a whole festival and nobody’s going to find your stash and steal ’em.”

The band’s members also share a word of warning: you should always question the cleanliness of a tinnie you find in a blow-up wading pool functioning as an esky.