Has anyone ordered and used the Joulies? http://www.kickstarter.com/projects/705...just-right

Here's my problem...whenever I put a fresh brewed drip in my nice insulated mug as I run out of the store, I always:

A) Burn my tongue because I have no patience when I try to drink it right away.
and

B) Have to wait forever for the damn thing to cool down. I'm talking an 45 minutes or longer sometimes.
and

C) I notice the same problem for my customers while they're at the shop. They have to wait a while for it to cool down, then if they take to long to sip on it (especially a 20oz), it gets cold and they end up not finishing the drink. I hate to see coffee get wasted, especially since they paid for a large but only drank half the amount. Plus, I get asked to "reheat" their coffee and you all know what they mean by that.

So, I'm very curious to know if these work well in (key point here) an insulated mug. There are complaints about the Joulies not being effective at all. http://boingboing.net/2011/10/26/coffee...eable.html However, after further reading down the posts, I discovered the effectiveness depends significantly whether your cup/mug is insulated or not.

Given the absolute necessity of a well insulated mug, instead of these bean shaped metal objects juggling around in your cup, why not just make a insulated mug lined with this "endo-exothermic phase changing material" instead and remove the problem altogether?

I know many of you have serious engineering and science degrees here so I'd love to here your thoughts.

I'm currently taking a chemistry class so I see the concept and it does sound interesting. if you look at a phase change graph (for example this one for water: http://www.atmos.washington.edu/2003Q3/...hanges.gif), you notice the temperature changes constantly but when it hits a phase transition it takes a significant amount of energy change to get it to change temperature and cross into that phase. So the key here is the 140 degree fahrenheit melting point. The Julie will heat in the coffee up to 140 degrees and continue to take heat from the coffee before it melts and continues rising again. I think it would be much more significant in effect if the material was changing from liquid to gas though. I suppose the mass would allow for more heat retention but honestly, when double walled mugs already keep my coffee hot for hours, that is the least of my concerns especially because it starts tasting nasty after a couple of hours. The cooling down is a cool trick though, but like you said, why not just make the mug more massive or fill the walls with this material?

EDIT: I hope I don't give away their secret, but it is probably just filled with wax. If you are a DIY, science fair kind of person, try drilling a hole in the exterior wall of a double insulated mug, fill it with wax, plug the hole, take a second identical but unmodified mug, stick thermocouples in each, fill both with hot coffee, and graph the temperature change in the coffee could be interesting!

EDIT 2: I just thought of something else that may be even more significant in reducing the temperature. What if you filled the walls with water and pulled the pressure down to 3psi or so. Then the boiling point of water would be at about 140 degrees fahrenheit. Vaporization takes a lot more energy than melting.

About these, I read on Sprudge that the inventors visited the White House yesterday. A quick look at their website tells me that they're starting to fulfill their original Kickstarter preorders at last and are now officially accepting new orders to be shipped ~12/1. In other words, you won't have to wait long to get your curiosity satisfied re: Joulies.

Oh man, I just read last week that the change in the temperature is just no significant. I will try and find that link.

EDIT: Here, see graphs

http://www.marco.org/2011/08/10/coffee-joulies-review

I use a single-wall ceramic travel mug with a silicone lid I picked up on clearance. It cools down the coffee fairly quickly, some would probably say too quickly. I'll usually pre-heat the cup with the extra water I prepare for my morning Chemex, but as I enjoy tasting the changes in coffee as it cools I don't sweat it and I enjoy the spectrum. I had tried a more expensive double-walled ceramic travel mug first, but the lid would pop off too often and the coffee didn't cool fast enough for my liking.

I used to use on of those stainless steel Contigo spill-proof travel mugs but they kept the coffee hot too long and I started to notice a metal taste (reminded me of a metal spring) when drinking delicate washed coffees so I switched.

I haven't tried the Joulies and can't comment on their effectiveness.

Randy G. wrote:I just posted my review of Joulies on my website (URL below). I finally got a set from Dave.. or maybe it was Dave, in Portland at the show. Tested them this morning using two identical mugs and duel channel data logging meter and found Joulies do exactly what they say- drops the temperature of a beverage to a drinkable temperature quicker and keeps it there longer. They work best in a well-insulated container, and would be most effective in a thermos bottle.

Nice article, Randy.

But they give you 54 minutes instead of 42 minutes in the "drinkable/ideal range"? Is that such a big deal practically speaking??

It would also work well for siphon or coffee from the Alpha Dominche Steampunk brewer that comes out rather hot. (but tasty)

I actually went to a poorly insulated mug to enjoy my coffee as it cools.