Insulating cold drinks

June 15, 2006 4:29 PM

Coffee cup sleeves: is there any reason to use one on a cold drink? The java industry is pushing the idea that it's not just for hot drinks. They claim that cold drinks stay cold longer thanks to the insulation (from your warm hands and the environment.) But is this scientifically valid? Isn't the insulation kinda negligible?
posted by Kirklander to Food & Drink (19 answers total)

It's valid. But it's probably not very significant, though I don't think I'd refer to it as "negligible".
posted by Steven C. Den Beste at 4:32 PM on June 15, 2006

The rate of heat transfer is all to do with the temperature differential, everything else remaining equal. The differential between a hot drink and ambient temperature on a cold day is much bigger than the difference between a cold drink and ambient temperature on a hot day, so the insulation is more useful. However it is still useful on a cold drink.
posted by unSane at 4:44 PM on June 15, 2006

If this is something like a stubby holder, then yes, it's entirely valid.
posted by pompomtom at 4:46 PM on June 15, 2006

I've done this for years. If nothing else, it keeps my hand from getting cold and wet.

Here in Texas, when it is hot outside, condensation forms on cold drinks pretty damn quick. A little cardboard sleeve goes a long way.
posted by Cycloptichorn at 4:55 PM on June 15, 2006

I'm sure it makes some difference, but not much. I think the main point of those things with hot drinks was to allow people to hold hot drinks comfortably, I doubt it kept them warmer significantly longer.

Similarly I doubt it does much for cold drinks. Might help enough at insulating frozen drinks from your hand to be worth it, but I doubt it would be worth it with iced drinks.

Easy enough to do some experiments. You just need some beverages, a thermometer and a timer.
posted by Good Brain at 4:56 PM on June 15, 2006

Response by poster: Thanks, Cycloptichorn -- maybe my perspective is thrown off by the West Coast weather and narrow temperature gap.
posted by Kirklander at 5:12 PM on June 15, 2006

They need to put them on ice cream containers - like Dairy Queen Blizzards - to keep you from freezing your fingers off. In the meantime, I use napkins.
posted by IndigoRain at 5:24 PM on June 15, 2006

Think about it - if that little cardboard sleeve can reduce the rate of heat dissipation enough to make it comfortable to hold the cup, then it is doing a significant job in keeping the drink warmer (or colder) for longer. Granted, it does nothing for the surface of the beverage.
posted by Dipsomaniac at 6:17 PM on June 15, 2006

Dipsomaniac writes "Granted, it does nothing for the surface of the beverage."

If you're talking about the surface at the top of the fluid, that's actually the best-insulated part. There's a layer of air between that surface and the cup cover; air is a great insulator.

Of course, there is convection to consider...
posted by mr_roboto at 6:25 PM on June 15, 2006

I'll second the stubby holder argument. Every beer-drinking Aussie male cannot be wrong.
posted by UbuRoivas at 6:35 PM on June 15, 2006

I'll third the stubby holder argument. Every beer-drinking Aussie female cannot be wrong.
posted by bella.bellona at 7:04 PM on June 15, 2006

As I used to say back in my drinking days, "If you are using a koozie, then you are drinking way too slowly."

I would say the same here. If I can't finish my cold beverage before it starts warming up, I need to order a smaller size or drink faster.
posted by flarbuse at 7:09 PM on June 15, 2006

Well, I was working at a coffee shop when they phased out styrofoam cups and replaced them with paper cups with separate cardboard sleeves for that Starbucks look, and even with the sleeves on, the hot paper cups of coffee were much less comfortable to carry than the styrofoam ones had been, I didn't find that the sleeves provided much insulation at all, even against heat. I imagine they'd be fairly useless against insulating a cold drink as well.
posted by ITheCosmos at 7:20 PM on June 15, 2006

IMO, the energy used to produce and transport coffee sleeves, then to transport them to the landfill (a few extra garbage truck trips maybe), not to mention the methane and other greenhouse gases produced by the decomposition of coffee sleeves in a landfill (god forbid they incinerate them!), means that coffee sleeves make a small contribution to hastened global warming and ultimately defeat the aim of keeping cold beverages cold. ;)
posted by salvia at 7:28 PM on June 15, 2006

Except, salvia, that sleeves are often used as an alternative to double cupping, which is an even greater waste of resources. IMHO, if you're environmentally friendly, you would praise cardboard sleeves and paper cups and denounce styrofoam cups as environmental hazards. Of course, the greatest way to help the environment is to bring in your own mug, which can be washed and reused. But consumers are much too superficial and trendy to do that.
posted by SeizeTheDay at 8:16 PM on June 15, 2006

When I worked for *$, there was nothing more irritating than retarded customers asking for a sleeve for Frappuccinos and iced tea (not to mention that most of them don't know the word and end up making some obscene gesture or making up a terrible word for it. I swear to you I heard a customer call it a cup skirt once). Most customers don't ask for them for preserving the intended state of the beverage but for comfort. People who want their drinks to stay cold or hot longer will use an insulated travel mug.

All that being said, the sleeve can't help in any significant way because it doesn't cover the entire surface area of the cup. So, even if the sleeve is helping around the midsection, the uncovered edges continue to lose (or gain) temperature at the same rate.
posted by jxpx777 at 9:16 PM on June 15, 2006

I use one for iced drinks that come in plastic cups because of the condensation. It avoids a cold, wet hand trying to grip a slippery, wet plastic cup.

jxpx777 what's so irritating and retarded about asking for a sleeve for my comfort? I'm glad you didn't work at my local coffee store.
posted by Joh at 10:03 PM on June 15, 2006

The sleeve insulates because the #1 conductor of heat out of (or into) the drink is your hand, holding it. Holding the sleeve seperates your hand from direct contact with the cup with an air cushion in the cardboard.

If anything, the industry is catching on that all sorts of customers ask for sleeves on their cold drinks anyway.
posted by mek at 3:51 AM on June 16, 2006

@flarbuse: I just want to say that, theoretically, you could also use a koozie to make it appear to the park [pdf] wardens that you're drinking a Pepsi when in fact you're drinking a PBR. Hypothetically.
posted by chota at 5:33 AM on June 16, 2006