Halloween Chocolate Melting Experiments

Ever wonder why chocolate turns white? It's not getting moldy. In fact, the white stuff is just another form of chocolate crystals, called Chocolate Bloom.

Cocoa butter molecules stack themselves into many different forms of crystals, and some are more stable than others. (Think of the difference of strength between a single Lego tower and an interlocked Lego wall.) When you melt the chocolate, the cocoa butter cools into crystalline forms that are less stable. Cocoa butter gets pushed out of the chocolate structure and reforms into white crystals.

Chocolate bar at the end of The Great Melting Race

Chocolate Bloom

Broken chocolate: notice the fissures where the chocolate has separated

Cocoa Butter Crystals

Imagine Children's Museum Signing

I had a great time at the Imagine Children's Museum in Everett, WA last Saturday, where I got to meet lots of kids, parents, grandparents, and fellow authors! Thanks to

If you ever have to set up your own candy experiment table, these experiments are crowd pleasers:

Author Beth Bacon joined us at the museum when she read her new picture book, The Book No One Wants to Read.

The grownups also had fun! These staff members are using air pressure to squash marshmallows--how small can they get?

And the fun kept spreading--one experiment made it all the way to the ticket office.

The Great Candy Melt-off November 2019

The Great Candy Melt-off November 2019: Who will survive?

The contestants line up on a foil-lined baking sheet.

The oven heats to 250 degrees F, and in they go.

The powdered dextrose of the Colossal Sours starts melting into a transparent syrup.

The melting middles of the Skittles bubble out through the hard candy shell.

Tootsie Fruit Chews melt together into a gooey Spumoni colored puddle.

The Twix bars expand and split.

The M&Ms shine as the glaze melts, while the Hershey bar exudes tiny oily drops.

The Sunkist Fruit Gel pulsates as it melts.

After everything sits in a fine melty state for a long time, the final death round starts: 300 degrees.

The Skittles melt into a rainbow peacock tail.

The Toosie Fruit Chews bubble into a brown sticky puddle.

The Sunkist Fruit Gem melts into a sparkly pink puddle, but the sugar crystals in the coating stay solid. They’ll survive until the temperature hits 320 degrees.

The Colossal Sours have gone nearly completely transparent.

Meanwhile, the M&M’s have cracked open. The adjacent Hershey bar is soft to the touch, but the M&M chocolate is hard and brittle.

The Warheads Chewy Cubes look untouched--until you see the shining glaze. Though the cubes themselves look unchanged, they skate along a shining puddle of melted sour crystals

Leaving the winner: Tootsie Dots!

Aside from a slightly dry and crunchy exterior, they retained shape and texture thanks to a secret ingredient: food starch.