Ever wonder how they make those hollow chocolate Easter eggs? It's actually quite an involved process that is patented. The patent number is United States patent 3961089. An item such as a hollow Easter egg is formed by inverting a molded chocolate shell onto another shell. The lower shell is formed with an inner coating layer, such as chocolate, while the inverted upper shell is given an inner coating layer that is in a fluid state when the shells are superimposed, so that some of the material of the inner layer flows onto and is welded to the surface of the previously formed inner layer of the lower shell. This forms an internal seam without any discoloration and is virtually unnoticeable. Sound confusing? That's probably why it's patented.
And if that explanation seems complicated enough, in reality it isn't even that simple. The process actually involves pouring the contents into the molds at certain temperatures at certain stages of the process. Also, the molds have to be of certain sizes in order to work correctly with each other. To give an example, and keep it as simple as possible, when making the popular hollow Easter egg, two molds of size 10 each are hinged together like a book and then are moved into a closed position. The molds are then formed with cavities, size 14. These molds are used to form the shell of the Easter egg.
These eggs will have a diameter of anywhere from five to seven centimeters. As for the temperature, the size 10 molds are formed at lower temperatures than the size 14 molds. The size 10 mold temperature is about 25 degrees where the size 14 shells are formed at about 28 to 30 degrees.
Generally speaking, the larger the shell the higher the temperature. In the above process there is going to be some excess material that needs to be poured off. The amount of material that is actually poured off is based upon the size of the mold itself. Unfortunately this is a wasteful process the smaller the mold. For small hollow chocolate items there is more excess than with the larger hollow chocolate items. This is why you will see more larger hollow chocolates made than smaller hollow chocolates.
To complete the process the molds need to be cooled in order to solidify the chocolate. While this process is going on the excess is drained off and in order to facilitate this, the mold needs to be slightly vibrated. The larger the mold, the more vibration that is needed.
The actual cooling temperature again varies depending on the size of the mold. In most cases the cooling temperature is about zero to minus five degrees in order to complete the egg from the mold. If you're interested, the actual inventors of this method were Amilcare and Dogliotti. The patent was filed for on July 24, 1974. So if you're wondering why you didn't get those hollow Easter eggs before that time, that's why. .
By: Michael Russell