News Review: Pumpkin Spice

"Retail sales of pumpkin offerings have experienced double-digit growth for the past several years, reaching nearly $350 million in 2013, according to market research firm Nielsen. And that figure doesn't count Starbucks pumpkin spice lattes…." 

Carmen Drahl, C&EN 

I admit to hoarding Chemical and Engineering News (C&EN) articles that mention flavors or fragrances. Or food additives. Or food regulations. Pretty much anything that mentions chemicals and things consumers consume. In addition, I recently discovered - to my joy - a section of their website called "What's That Stuff" (which is also the header of certain articles in the magazine).

I'm far from the first and surely far from the last to bring this topic up, but the most recently featured stuff was the (in)famous "pumpkin spice flavor" in the October 27 issue. According to this article the complexities of natural flavorings don't necessarily need to be present for the human brain to understand what a flavor is meant to be. "Pumpkin spice" is considered to be a mixture of spices containing around 340 flavor-relevant compounds. However, given just a fraction of those compounds and concentrating on the inclusion of key aroma and flavor molecules - about 15-30 components of the spice mixture's complete profile - the overall taste is interpreted as true-to-nature by the consumer.

I wrote a blog post on another website on Natural and Artificial Flavors where I basically concluded that both have their pros and cons but that artificial flavors aren't any "scarier" their "natural" counterparts. That said, there's a lot more that goes into making the perfect product that isn't flavor related. Take, for example, that famous Starbucks Pumpkin Spice Latte.

Is Your Coffee Toxic?

Sugar, preservatives, coloring. There's probably even some sensation-generation molecules in the mix. Things to make warm and cozy feelings all over your mouth. The above info-graphic might be exaggerating a bit about the side effects but then again….

But I digress.

I wanted to tell you about the main chemicals involved in pumpkin pie spice according to this article in C&EN. Zingiberene (ginger), (E)-cinnamaldehyde (cinnamon), sabinene (nutmeg), eugenol (clove) and possibly cyclotene (maple or brown sugar flavor) and - everyone's favorite -  vanillin. Other, smaller contributors to the wildly popular pumpkin spice flavor include allspice, anise, and mace. Find their mug shots below….(thanks to Wikimedia Commons for having awesome drawings of chemicals and pictures of foodstuffs). In addition to the images, definitely check out this resource from NBC to learn more about the molecules in these spices.

Zingiberene

(E)-cinnamaldehyde

Sabinene

Eugenol

Cyclotene

Vanillin

Just as the pictures I've paired with the chemical names show very different things than what the chemicals themselves are, key flavor compounds are representations of the full flavors found in nature. Like the images these critical components of a flavor are enough to give the brain context and therefore understanding for something that is as poor a representation of the true thing as still, flat drawings of an-ever-moving molecule. Pretty tricky on the food industry's part, don't you think?

All of this begs the question: what aroma compounds are actually in a pumpkin? As it turns out real pumpkins, like, the kind from a vine in a patch contain a very different set of aroma compounds. If you've ever taken a bite out of a pumpkin at Halloween (anyone?) you'll recognize that they aren't sweet and have a subdued not-all-that-appealing flavor.

According to this article in Scientific American, pumpkins smell like vegetables or squash (not surprisingly) because of "leaf alcohol" or cis-3-hexenol. Other major flavor and fragrance compounds include 2-hexenal, diacetyl, 2-meythlbutanal, furfural and pyridine.

Credit: "Pumpkin, Hold the Spice" Scientific American
Clockwise, from top left: cis-3-hexenol, diacetyl, 2-methylbutanal, furfural, pyridine

This is a good chance to look at some of these totally natural molecules and get some perspective. Things created in labs aren't necessarily more harmful than things created by plants. I mean, take water hemlock, for example (my go-to for putting nature on the spot).

This isn't to say that all chemicals made in labs are fine and dandy. In fact, there are loads of problems with chemical formulation and manufacturing due to waste, toxic materials usage, and more. But both sides of the natural/artificial arguments have their pros and cons. Take diacetyl, one of the chemicals found in pumpkins. It's responsible for the buttery aroma of pumpkins when it occurs naturally and is harmless. However, in its pure form - or in large quantities on microwave popcorn - it poses a risk of severe lung disease.  Pyridine is another chemical mentioned above and it's commonly used as a solvent in the lab which is certainly not something you'd want to ingest.

So, in conclusion, while pumpkin spice flavors might not contain any real pumpkin they do contain some of the key aroma compounds from the spices they're supposed to represent. And while this might be an unsatisfying answer for consumers the chemicals used are simply mimics of things found in nature. In short, I'll continue to eat my pumpkin spice oatmeal, thanks very much.

Ashley