Sacrificing fruitcake for science

by Ulysses Torassa
Dec. 13, 1998
©1999 San Francisco Examiner


Exploratorium staffers use the dessert as basis for experiments

Pity the poor fruitcake - the butt of jokes, left uneaten, to harden andgather dust. Used as a doorstop, a paperweight, rarely finding its rightful place on the holiday dessert plate.

The picked-upon pastry was subjected to even more indignities Saturday, as Exploratorium staffers burned, rolled, measured, dropped, sat on and even excreted the dense dessert. All in the name of science, allegedly.

Since summer, Exploratorium employees and visiting teachers have been demonstrating fun science experiments that can be done with commonly found, cheap objects - such as balloons, film canisters, soda bottles. With the holiday coming up, they decided to take advantage of all the surplus fruitcake that would undoubtedly be available when school starts up again in January.

"I thought a great science experiment would be just to taste it, because has that ever happened?" asked Lori Lambertson, adding insult to injury.

A staff member with the museum's Teacher Institute, Lambertson was easier on the downtrodden treat than her colleagues were.

She simply measured a round fruitcake and compared its circumference with its diameter to come up with the famous geometrical number "pi.' She called her experiment "Turning Fruitcake Into Pi.'

Others weren't so kind. Karen Kalamuck, who specializes in biology, pulverized fruitcake in a blender with water and then stuffed it through two plastic tubes that looked like sausage casings. Her experiment's title: Festive Feces.

"This is your colon on fruitcake," she said.

One tube held just the fruitcake and water mixture. In the other, she added the laxative Metamucil, to demonstrate why fiber is so important in our diets.

The unadulterated tube was emptied in a yech-inducing splat.

But Kalamuck had to strain mightily to squeeze out the contents of the fiber-enriched tube, as the audience groaned in sympathy and revulsion. It was a you-had-to-be-there moment.

"It's gross and disgusting - exactly the kind of thing sixth-graders love," said Kalamuck.

The event is patterned after the "Iron Chef," a Japanese competitive cooking show in which two cooks are presented with a single ingredient and told to construct an entire meal in which it is part of every dish. The audience watches their frantic efforts, and then judges taste the outcomes and proclaim a winner. It has a cult following in the United States.

Called "Iron Science Teacher," the Exploratorium version has used balloons, straws, aluminum cans and soda bottles. When empty film canisters were chosen, one teacher made Alka-Seltzer-powered rockets, and another cut it open to reveal a sine curve from trigonometry.

"Our philosophy at the Teacher Institute is to show that science is everywhere and it can be done anywhere. You don't need fancy equipment," said Linda Shore, co-director of the institute and mistress of ceremonies for the show. It was also carried as a live broadcast on the museum's Web site.

The staffers knew a few weeks ahead that fruitcake would be the common ingredient. Besides math and biology, the demonstrations also illuminated the chemical energy of fruitcake as it burned fiercely in a test tube, how it obeys the laws of motion when it is dropped from a great height and even its density.

Don Rathjen, a retired physics teacher who also works at the institute, pointed out that fruitcake appeared to have about the same weight-to-volume ratio as water. So would it float?

It did. Rathjen then sat on the fruitcake to increase its density, although he forgot to dunk it back into the water to prove his hypothesis - that the more compact object would sink.

For his efforts, Rathjen won the loudest cheers from the audience and walked away with the first-place prize - a fruitcake.

©1999 San Francisco Examiner