A wise man once suggested that if you truly want to make an apple pie from scratch, you had to start at the beginning—the very beginning. Back when Carl Sagan uttered that famous line, all the while butchering that poor pie*, he was speaking of taking elementary particles and constructing atoms in which to bind into chemicals. This is sort of difficult. But what if we met Carl halfway?
Take this pie. If I told you that this was an apple pie, I would be lying. It looks like an apple pie, it smells like an apple pie, and it even tastes like an apple pie. But the truth is that it contains no apples. So what gives?
Some of you have already guessed that this is a Mock Apple Pie, made out of crackers, sugar, and cream of tartar**. When this recipe crossed my inbox (Thanks Rebecca!) I knew I had to try it. See, ever since I began co-habitating with my girlfriend in July, I began to turn our kitchen into a makeshift chemistry lab—staying up late into the night chasing after some household-accessible, scientific oddity. It’s like that early scene in Das Boot (or any submarine movie, really) where the daring captain takes the sub as deep as it can go to test its limits. This is what I am doing to my poor girlfriend. Nonetheless, the project was perfect: Chemistry with an edible conclusion. From the recipe, I discerned the basics immediately: Here was a pie that worked off of the distilled elements of an apple (see where I’m going with this?) rather than using apples themselves. As I prepared the ingredients, I began to research the history of this “chemistry pie.”
I was surprised that I had never heard of it before now, especially since the internet abounds with recipes and anecdotes from the various trying times that spawned their creation. History has it, that at some point in the 1800’s, somebody figured out that you could fake an apple pie without having any apples (which used to be hard to come by, and would spoil too quickly on a wagon train). As such you can read stories about this pie in context to the western expansion, the great depression, and the World Wars. Anytime you wanted that “American Apple Pie,” but circumstances prevented you from getting real apples, this recipe would do the trick. You’ll see later how “close enough” fits into this equation. So how does it work?
My initial hunch was that various chemicals in the ingredients—such as the cream of tartar, which is key—interacted to form an ester. Esters are everywhere, and used in countless applications, but for our purposes (Taste) an ester can be thought of as a basic building block of flavor and aroma. Simple esters, such as banana oil, can be made in a lab from scratch. No need to pull the banana flavor out, its simple enough that you can produce it. Many flavors are the combination of several esters, essential oils, and acids. At any rate, the more I read about esterfication of molecules, that is the production of an ester using alcohol and sulfuric acid, the more I began to realize that the chemistry happening in the pot was probably not that advanced. Turns out I was right.
I’m getting ahead of myself. How do you make this stuff? The recipe I followed was found here, on The Awl. I deviated by adding a dash of lemon and some lemon zest to the syrup. What you do is boil water, a ton of sugar, and cream of tartar until dissolved. Then you add butter crackers (Ritz in this case) and let them cook. At first, it looks like crap, but after three minutes you are greeted to a frighteningly accurate facsimile of a gooey apple pie filling. Now, what you’re doing in this step is basically building apple pie filling. You take water, sugar, and “pulp” in the form of gluten to create a golden, syrupy mess. The flavor comes from the cream of tartar. At this point, the whole universe is asking, “What the hell is cream of tartar?”
Potassium bitartrate is the salt of three different acids. It is used to thicken egg whites when making meringues and in my childhood, was put into homemade playdough for some reason. That’s just how my mom rolled. It is a natural byproduct of winemaking (in the form of the sediment that collects in the casks and bottles) and comes from the tartric acid that gives grapes their flavor. Here’s the kicker, you know where else you find tartric acid? Apples. Specifically, it provides the tartness found in both apples and grapes. Just add malic acid (found in many unripe fruits) to the mix, and you have a Granny Smith. So it all comes full circle. Carl Sagan would be proud. You have managed to engineer an approximation of an apple, using some of it’s key ingredients. Entropy prevents you from ever cooking them until you find yourself with a whole apple in the pot, but we can meet entropy halfway as well.
But it gets even weirder. So you’re not eating an apple, but researchers have found that what you are eating is merely “close enough” and your brain fills in the rest. It smells like apple pie, it looks like apple pie—what happens next is all in your head. On top of that, I added cinnamon, butter, and a dash of lemon to further seal the illusion. Most of what makes an apple pie “smell” is the crust and the spices, after all. Once the filling is done, all that is left to do is bake it as you would a normal pie. Thirty minutes later, and voilà! You are the proud owner of a fake apple pie.
In closing, I have some bad news: As a foodstuff, this pie is complete crap. It has more than twice the calories as a regular apple pie, and it probably has no nutritional value whatsoever. This is a “Cracker Pie” filled with syrup. I do not recommend making this a regular thing. That said, tomorrow, I’m bringing some of the pie to work for testing. Perfectly ethical right? From my research I found that people tend pick out the various ingredients. Some thinking it tastes like a lemon pie, others just tasting the sugar. In the interest of further research, I’d love to try omitting the cream of tartar—or any of the other ingredients—and seeing how blind tasters react. Will they still think its apple? How much approximation is needed?
If any of you at home want to give this a go, I recommend the recipe below.
Pie crusts (either out of a box or premade)
2 cups of water
1 1/2 half cups of white sugar
1 1/2 teaspoons of cream of tartar (potassium bitartrate)
25 “buttery round crackers” (Ritz)
1/2 teaspoon cinnamon. (I used more)
2 tablespoons butter.
1 tsp Lemon
Lemon zest for zing
Preheat oven to 450 degrees.
Mix water, surgar, lemon, and cream of tartar into a pot and boil.
Add Ritz crackers one by one. Ignore any clumping, this will keep your pie looking like chunky pie and not like syrup. Cook for 3 minutes.
Pour into the pie crust. Add liberal amounts of cinnamon and lumps of butter. Then cover the pie with more crust. Bake for 30 minutes.
The pie really works best once it’s cooled fully. When it’s hot, it tends to be a little oozy to be convincing.
Addendum: The pie was a great success at work. Even those who I had earlier clued in to the trickery found it hard to believe that there was no apple in the pie. I owe everybody a real pie now.
*He could weave the stars into beautiful poetry, but man, don’t let him serve at your next birthday party.
**Readers of Sci-ence.org may recognize this ingredient from my piezoelectric crystal experiments. Suffice to say, I had tons of the stuff around.