Wolfgang Puck self-heating can hacking…

Wolfgang Puck self-heating can hacking…

Awhile back I wrote about the new Wolfgang Puck self-heating coffee containers that took 10 years and $24 mil to develop. Well, I managed to find them in a local store and bought them to take apart to see how they work. Once activated, they reach 145 degrees in about 6 minutes. This isn’t a review of the beverage, it’s all about the stuff that makes the liquid hot, how it works, pictures and links to patents….The self-heating cans are made by a company called OnTech. Their technology section talks a it about how their heating works.

The OnTech self-heating container is built from two main parts: the container and the actuating “puck.” The container is composed of an inner cone that holds the mineral (Calcium Oxide), and the outer container body, which holds the beverage product. The puck holds water and is sealed by a foil membrane. All components are made from FDA-approved materials.

On to the dissection…
The container looks like there’s a lot of liquid in it, but I later found out that it’s actually a lot of heating material.

Simple instructions, pop the bottom, press it in. Watch for the pink spot to turn white.

It worked fine, it was warm, took about 6 minutes and heated to about 140 degrees. I then used a can opener to pry to the top off.

Here’s the container without the fancy outside, I like this design better.

Here’s the pressed in bottom. Once pressed the foil inside breaks and water drips down to the calcium oxide and starts the reaction.

Here’s the inner heating element, I sawed off the outside to reveal the inner chamber.

This thing is constructed of extremely heavy duty plastic, and it’s quite dense. Which makes sense; it’s filled with minerals.

I chopped the top off and poured some of the powder / mineral in to a glass.

Then poured more out.

It fills about 8 ounces, it’s white and powdery, but contains little multi-colored rocks.

Here’s the water release system.

The inner ring presses through the foil.

The calcium oxide, dry.

The calcium oxide wet.

So there it is, an exothermic reaction (gives heat off) with water and calcium oxide. You can easily remove the liquid and use it for something else. I’m not sure what, but I think there are some uses for this. It’s constructed like a tank, so I bet military and outdoors people might be using these.

One of the best uses might be to remove all the materials (before they’re heated/water added) and show how chemical reactions can be used for something tangible for students. You could also likely do some neat things with the materials for experiments that require a small amount of heat.

The patents
On the bottom of the can there are two patent numbers, here’s what the patents are for.

United States Patent 5,461,867
Scudder , et al. October 31, 1995
Container with integral module for heating or cooling the contents

An outer container for holding a material, such as a food, beverage or medicine with a sealed thermic module inside the container. The thermic module contains chemical reactants that mix upon actuation of the container by a user. Mixing of the reactants produces an exothermic or endothermic chemical reaction, depending upon the reactants selected. The contents of the outer container surround a portion of the outside surface of the thermic module, thereby facilitating conduction of heat. The thermic module has a hollow module body that is closed at one end and a module cap that seals the other end of the module body. The module body contains the solid reactant, and the module cap contains the liquid reactant. The module cap has a tubular section with a flexible member closing one end and a breakable barrier closing the other end. With the exception of the barrier, the cap is of unitary construction. The cap has one or more integrally formed prongs extending from the inner surface of the disc toward the barrier. The prongs move in an axial direction toward the barrier and may also spread apart radially when the outer surface of the flexible member or an actuator connected to it is depressed by the user’s finger. The dual motion of the prongs in both axial and radial directions promotes complete puncturing of the barrier and thus fast mixing of the reactants.


Scudder , et al. May 6, 1997
Container with integral module for heating or cooling the contents

An container for holding a material, such as a food, beverage or medicine, includes a cap and a container body. The container body has a material cavity unitarily formed with a reactant cavity. The reactant cavity contains a solid reactant, and the cap contains a liquid reactant that, when mixed, produce an endothermic or exothermic reaction, depending upon the reactants selected. The cap has a tubular body section with an actuator disc closing one end and a breakable barrier closing the other end. With the exception of the barrier, the cap is of unitary construction. The cap has one or more prongs extending from the inner surface of the disc toward the barrier. When a user depresses the actuator disc, it flexes inwardly and moves the prongs toward the barrier. The reactants mix when the prongs puncture the barrier. Heat transferred between the two cavities heats or cools the material. The wall of the container that defines the reactant cavity may be pleated or corrugated to promote heat transfer.

Click the link(s) to read more and to see the images. I’m somewhat fascinated by self-heating and cooling technologies and how they’re going to be entering our food distributing and consumption in the next few years. I think these types of containers might change the vending machines with the types of beverages and foods they distribute, and of course there are also some recycling strategies for these new cans? Anyway, if you come up with any cool projects let me know. I have a couple I’ll be posting up soon.

20 thoughts on “Wolfgang Puck self-heating can hacking…

  1. sej@aol.com says:

    When my parents’ neighborhood was flooded, and the power cut for a few days, they recieved from FEMA a stack of self-heating TV-dinner type meals. (The only ones they had left when I last visted were lasagna, but apparently there was a wider variety.)

    As I recall, you added your own water to the heater pack, tucked everything inside the box, and waited.

    My folks reported it worked quite nicely.

  2. sej@aol.com says:

    Oh, here we go. Heater Meals’ website:


  3. StevePoling says:

    The last MRE that I bought at an army surplus store included a self-heating pad with instructions for use in the field. It appears to be the same exothermic reaction as described here. And the materials seem to be packaged in a more hackable form.

  4. BRodda says:

    Just to let you know that Calcium Oxide is better known as Quicklime (Wikipedia link is http://en.wikipedia.org/wiki/Quicklime). This stuff will eat through your hands fast and you need to be really careful when playing with it.

  5. gg2 says:

    Wonderful idea for emergencies. Terrible amount of waste for casual convenience. Might be interesting for use in conjunction with some kind of thermocouple for creating a small electric current for powering a transistor radio or flashlight, though we do have windup generators for that purpose e.g. Baygen.

    And I sure hope the hell Homeland Security is reading this. These things should be banned from air travel because they could probably be used as components in or concealments for terrorist devices of various kinds, which I won’t describe in public places.

    It’s not often I get negative about a new technology, but this one really does open up a new dimension in concealed terrorist devices, and really should be banned from air travel.

  6. Jetlag says:

    MRE heaters (and HeaterMeals heaters) use less and probably different “minerals.” There are two versions with different “minerals” and amounts of water. They are not self-contained though because they release large amounts of hydrogen gas (and something that stinks). I have a pretty good supply of them if anyone has any ideas. I think I’ll have to buy one of those coffee things just so I can have a trashcan cup. Now, to go read that quicklime link…

  7. LdyCoffee says:

    Wow, thanks for taking apart the Puck Coffee containers! I was dying to do that myself as I’m one of those who likes to know how things “tick.” Its a fascinating product, don’t you think?

    I buy the Puck coffees for astronomy “parties” and like them. The coffee heats up very well and doesn’t cool down quickly. I only wish that they had unsweetened flavors.

    These are great to take on late night adventures and will keep us away from places like Starbucks for now! Thanks again for taking it all apart. Keep up the good work!

  8. irmavep says:

    Regarding your Wolfgang Puck self heating cofee page, I just bought the self heating can of coffee and had the worst experience. That button on the bottom would not press in, I had to bash it in. Then the green water barely dripped down. It heated up a bit but not that much. When I tried to turn the black top to open the darn thing i needed a darn vice. The WORST part was when I took a sip. It tasted like chemicals and not like coffee. I was literaly scared that I was poisened. I will not purchase again.

  9. TiminCO says:

    I brought one along on a mountain ascent in January.
    Didn’t heat up very well at 12000′. If altitude is a factor, I doubt then that it’ll work at most of my favorite camping sites.

  10. oceaniaNS says:

    one of these things blew up about 2 weeks ago. heard it on the local news. local grocer pulled it from shelf……………

  11. Scott Wedge says:

    I loved these things for hunting never had a problem with them plus it tasted good I was nice to have a hot drink in the cold deer or small game hunting

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