Easter Candy Diet Coke Fountain

I spent a whole afternoon trying different kinds of candy in Diet Coke geysers to see if anything could approach Mentos. I had OK luck with Sweethearts, and Sweet Tarts, which seem to have the right kind of surface (slightly pitted) but aren't heavy enough to drop immediately to the bottom of the bottle like Mentos do. Regular jelly beans were a failure--I think they're too smooth for the soda bubbles to form quickly on their surface. But one candy made me want to try again. Guess what we were doing all evening?

Here's are two nice Coke Zero geysers done with bumpy Nerd jelly beans.

Why do the bumpy Nerds create such a good geyser? My guess is that it's because they have a lot of extra surface area, because all those bumps stick out so much. That gives the soda bubbles even more space on which to form, and so the bubbles can form quickly.


So how do the bumpy Nerds compare to Mentos, geyser-wise? I tested Mentos, using the same amount of weight as I had with bumpy Nerds (10 g). Here was the result:
I had such high hopes, but the Mentos still won. This time.

By the way, when I used this experiment today I tried out the Steve Spangler Mentos Geyser Tube. (Steve Spangler is the person who popularized the Mentos/Diet Coke experiment in this video.) The tube works quite well, sending a fountain much higher than if you drop the Mentos in from a cardboard tube, and you're also far away from the mess so you're not nearly as likely to get Coke all over your clothes. Of course, there were drawbacks as well--once I forgot to screw the top on tightly, and the exploding soda pushed the tube right off of the bottle. Another time the bottle fell over when I pulled the trigger string (though this may be because I had to replace the pin, which I lost, with a nail which worked great except when it didn't). So, if you use the Steve Spangler tube, use it right and don't lose the pieces!

XKCD and Cadbury Eggs

XKCD has its own version of Find Hidden Candy, using Cadbury Eggs. (This work is licensed under a Creative Commons Attribution-NonCommercial 2.5 License.)

Easter Chocolate Pudding Chromatography

Mixing up some boxed chocolate pudding for my daughter's birthday party, I committed the same mistake as Matthew McConaughey in The Wedding Planner talking about brown M&M's--assuming that because it was chocolate, and that it was brown, that the brown color was all chocolate. (When we make chocolate pudding from scratch, with real chocolate, it's brown!) But a glance at the box told me otherwise--just like the coating on brown M&M's, Jell-O chocolate pudding has red, yellow, and blue food dye.


Naturally, I had to go looking for the dye. I wish I'd done the experiment before I mixed the pudding--diluting the pudding with milk made the colors harder to see. But I did get some color separation.
I don't know why I didn't see any blue. Maybe because the pudding was mixed with milk by the time I thought to test it, diluting the colors? Or maybe there just wasn't very much. There isn't much blue in M&M's.

We went ahead and used the chocolate pudding for my daughter's birthday party, turning "chocolate dirt pudding pots" with gummi worms and cookie crumbs into Easter egg hunting treats.

But my kids ended up not liking the pudding. Guess they're too used to the real thing.

Swollen Gummy Geckos

More gummy fun with the gummy gecko my 7-year-old begged me to buy (at the hardware store of all places!) With all of that gelatin, our gummy gecko absorbed lots of water. Though it didn't double in length like a gummy worm, when we left it in water it sure swelled up! (One interesting thing: since this gecko floated, unlike our gummy worms, it still had a few areas on the spine that didn't actually get wet. See the knobbly back breaching the water like a prehistoric aquatic dinosaur?)

Fun Conversation Heart Experiments

Check out the website at Inspiration Laboratories for some more experiments with conversation hearts, like testing them with baking soda, dissolving them in hot/cold water (I prefer to do this with M&Ms or something brightly colored that dissolves quickly, because you can see the reaction happen faster, but this certainly works), or using vinegar and baking soda to make the hearts dance. Fun ideas!

And thanks to Tricia at twobigtwolittle.com for blogging about the Candy Experiments book and linking to the Inspiration Laboratories site!

Ingredients and the Food Industry

This well-prepared video talks about what the food industry can do to improve public health--but since they have no incentive to do so, what we can watch for on labeling and how we can make better decisions.

We've also noticed this kind of thing with our Find Hidden Candy experiment. Gummi fruit snacks are practically indistinguishable from gummi worms, except that they have more vitamins; "healthy" cereals can contain 20-30% sugar (while sugary cereals can contain more than 50% sugar); and one bottle of orange soda has as much sugar as 22 peppermint Lifesavers. Hidden candy, for sure!

Candy Experiments on Evening Magazine

Evening Magazine got a Facebook tip about candy experiments, and came out to see what it was all about.  We had a lot of fun demonstrating our experiments--especially the kids.  They didn't have room for all my explanations, but most of it's on the website (or you can buy the book!)

Watch me and my children doing experiments here!

Floating Geckos

When we saw the Sour Gummy Geckos in the hardware store, my 7-year-old demanded that we bring them home for experiments. First experiment: when we put one in water, why did it float?


Gummi gecko floating in water

Only when the gummi gecko had absorbed water and expanded could we see the reason it floated: tons of tiny air bubbles.


The bubbles are also probably the reason the candy is opaque, not transparent like most gummies.