Even better, my workshop mate Black Crane Creations is a wizard with silicone and she just bought this food safe batch to cast pumpkins. I asked her to take a few photos and sum up how she did it so we could share this awesome Halloween treat with you.
It is time for another guest entry, from Black Crane Creations this time:
To turn small fancy pumpkins into delicious edible chocolate sculptures
This is how:
Acquire a few palm sized pumpkins of your choice. Can both be bumpy and smooth. Make sure they are clean by wiping them with a damp cloth and removing any dirt that might be stuck in crevices.
Then get some FOOD SAFE silicone putty. I use Silicone Plastique from The Cake Decorating Company. A 400g kit is usually enough for 4 small pumpkins.
Sadly I didn't take any pictures of the molding process, but the pictures of the finished molds should give you an idea on how to proceed.
The silicone is easy to mix (part A and part B, equal parts by weight or volume). Knead until an even color. You have around 15min work time, a warmer environment makes it harden faster so keep that in mind and don't make more than necessary at the time. I usually use half of what's in each box for 1 pumpkin and it uses around an hour to harden completely.
Save a 1cm thick roll of putty long enough to ALMOST circumcise the pumpkin for later. I usually roll out the rest of the silicone putty and flatten it a bit before applying to the pumpkin. This will be used to make a sturdier edge where the opening of the mold will be.
Make sure to squeeze out any air bubbles that may form while covering the pumpkin. If the mold ends up too thin a few places, patch those areas with more putty. Just press the putty on and around your pumpkin.
When the pumpkin is evenly covered in silicone we now take that 1cm thick roll and apply it to the outside of the mold. Placement varies depending on the shape of the pumpkin. Long oval pumpkins like the green and light green one needs to have the seam from stem to bottom. Rounder flatter pumpkins can have it across the belly. This is very important that we do or else we won't have a proper edge to clamp the different mold areas together when casting the chocolate/candy melts. Make sure it does not go all the way around since we need an area of the mold that will not be cut when we later do the incision for removing the mold.
Front of mold
Back of mold
A different mold (green pumpkin) to show the difference
Now let the mold harden (about 1 hour).
When hardened grab a scalpel or sharp knife and start creating an incision on that edge we made. Look at the pictures to get a good idea on how to do it. Make sure that you cut in a wave-like pattern. This will make sure the mold doesn't slide around when clamped together. ONLY cut 75% of the way around. You MUST leave at least 2-3cm, preferably 5cm, of the mold intact.
Now we can start prying the mold off the pumpkin. Make sure to be careful, especially in areas where the silicone is wrapping around bumps or at the edges of the mold. The silicone can rip so be careful!
When the pumpkin is removed the mold is ready to use!
Tips for casting:
I use candy melts since I am horrible at tempering chocolate (comes in different colors). You need a rather thick layer so I usually melt up a big batch(the ones that get very liquidy are best), pour it into each mold half, close the mold and then rotate it to get an even layer on the inside.
It takes a bit of practice to get perfect cast, but the good thing is you can always just remelt the candy melts/chocolate and try again.
Yummy chocolate pumpins :D
You can contact Black Crane Creations of you have any questions about silicone :) I'll be sure to ask her to show us more silicone work in the future.