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Food Science


Composing apple pi and an ode to pi

by Tien Nguyen
March 10, 2019 | A version of this story appeared in Volume 97, Issue 10


Image of pies with pi symbol on crust.
Credit: Shutterstock
Slice of pi: A classic way to ring in Pi Day

Homemade apple pi

Pi, that powerful constant describing the ratio of a circle’s circumference to its diameter, has captured people’s imagination for more than 2,000 years.

Yet the celebrated number has only recently been the focus of celebrations, with the introduction of an international holiday known as Pi Day on March 14, 1988. Originated by physicist Larry Shaw at the San Francisco Exploratorium, the first pi party was no pie-in-the-sky affair. It featured participants marching in a conga circle and eating, naturally, pie.

Pie is the unofficial food of Pi Day; its symbol, π, is often carved into pie crusts. Newscripts reader and lifelong pi and pie lover Rick Gilmour has taken the tribute one step further: baking pi into the recipe.

“I’ve always been fascinated with pi,” says Gilmour, who worked at CAS, a division of the American Chemical Society, for more than 30 years and is now retired. As a schoolboy, he “couldn’t bear to throw away digits” and memorized pi to about 15 significant figures. Later, in college glee club, Gilmour and his friends would wonder whether music could be written in π/4 time instead of 3/4 time. “We figured it would be a test of the conductors to get that decimal approximation just right with their baton.”

Now he has come up with a recipe for “apple pi.” Loosely based on a traditional recipe, his version uses the first 23 digits of pi’s decimal approximation in their correct order in the ingredients. “To do so requires the use of some unusual, and even improper, fractions,” he says.

The most challenging part, Gilmour says, was realizing that he would need to mix up the ingredients instead of listing them in the order they are used. Though he hasn’t tried the recipe himself, he says the recipe proportions should be valid. “I’m still looking for a tablespoon measure graduated in 38ths.”

3 c sliced apples
1/4 tsp salt
1/5 tsp nutmeg
9/26 c ice water
5/3 c all-purpose flour
5/8 c solid shortening
.9 tsp salt
7/9 c sugar
32/38 tb butter
4/6 tb flour
2/6 tsp cinnamon


Pi poetry

If baking isn’t a strength, consider a poetic approach to round out your celebrations by composing a poem in pilish, writing in which the number of letters in each word is equal to the corresponding digit in pi.

Inspired by Gilmour’s example of taking pi tributes up a notch, the Newscripts gang developed a pi poem–haiku mash-up: a piku. While others have offered various piku constructions, our version follows pi poetry rules as well as the structure of haiku of three lines with five, seven, and five syllables.

As an example, here’s one Newscripts writer’s ode to apple pie using the first 13 digits of pi (3.141592653589):


How I love a slice
Smothered by creams, light and white
Honoring childhood


We’d love to read your piku as well.

Tien Nguyen wrote this week’s column. Please send comments, suggestions, and piku to



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