Have you ever eaten a banana Laffy Taffy and thought, wow, that really tastes like an actual
banana?
Me neither.
I guess I've always kind of considered the banana Laffy Taffy to be the gold standard
for banana flavor, which is kind of weird now that I think of it...
Today, I want to figure out what is responsible for that super distinct artificial banana
flavor, if actual bananas even have it, and which bananas might have the most of it.
In other words, I wanna figure out which banana is the most bananay.
It turns out a single molecule is responsible for that artificial banana flavor, isoamyl
acetate.
And yeah, there is isoamyl acetate in actual bananas.
So why don't actual bananas smell and taste like banana Laffy Taffy?
The main reason is that bananas have many more smelly compounds than just isoamyl acetate,
but there is one banana variety called the Gros Michel that some people seem to think
tastes and smells a lot like a banana Laffy Taffy.
Today, at least in the United States, the standard grocery store banana is the cavendish.
I ran out of bananas.
I ate all of them.
But back in the day, it was the Gros Michel, which was really popular, but then got all
but wiped out because of a fungal plague in the early 1900s.
I came across a story that artificial banana flavor, that ISO animal acetate was based
on the Gros Michell.
So I asked a food historian, if that was true.
Banana flavor, artificial banana flavor, actually I found came before Gros Michel or even before
bananas were common in American marketplaces.
So it's quite possible that a lot of Americans tasted a banana flavored thing, a synthetic
chemical version of banana before they tasted Gros Michel.
There are over a thousand banana varieties out there.
And it turns out that banana flavor wasn't originally derived from any of them.
Isoamyl acetate came from scientists in the 1800s playing around with carbon based molecules
in the lab.
And if you've ever taken an organic chemistry class, maybe you've made it too.
It's an ester, which is any molecule with a carbon, two oxygen and another carbon arranged
like this.
You make isoamyl acetate by mixing isoamyl alcohol with acetic acid, adding a catalyst,
heating it up and voila!
You've got something that smells like a banana Laffy Taffy.
So back to those scientists in the 1800s.
They're smelling and tasting these fruity esters that they've created in a lab because
it was the 1800s and chemical safety was not yet a thing.
And also the life expectancy was like 23.
So who really gives a...
And one of those esters just happened to match the smell and taste of what they considered
“banana.”
We were psyched to get our hands on some Gros Michel bananas to taste test to see if we
thought they tasted more like a banana Laffy Taffy than the bananas we're used to eating.
If I'd immediately commented on what it tasted like, I would have said, this is identical
to a cavendish.
But the aftertaste is very different.
It's really sweet.
Let's try this.
Very similar after taste.
With this, you're just getting the aftertaste of this.
I'm very curious to see what the rest of the team thought.
Speaker 3 (03:40): It tastes like a banana.
It's pretty similar to a cavendish.
It kind of tastes exactly the same.
It looks just like a regular grocery store banana.
This tastes identical to a grocery store banana.
There's no difference.
We also sent some Gros Michele bananas to our animators, but like everything else with
them...
I guess I'm the only person on our team with a sophisticated enough palate to notice that
the Gros Michel tastes a bit different from the standard cavendish.
If isoamyl acetate is the dominant compound in theGros Michel, that could be why some
people think it tastes a lot more like a banana Laffy Taffy.
So I want to figure out if the Gros Michel has more iso amyl acetate compared to other
banana varieties.
The first step is getting those smelly banana compounds out of the banana to figure out
how to do that.
I called up Dr. Pam Dalton at Monell Chemical Senses Center.
You could make essentially sort of a banana essence by crushing a banana in some pure
alcohol and letting it steep for a while and then draining the solid parts out.
So I took Dr. Dalton's advice and I did that for a bunch of banana varieties, including
the Gros Michel and the cavendish.
Once they were ripe, I weighed out varying amounts of each of them starting with 10 grams.
And then I let them soak in 60 mils of 95% ethanol.
And then just kind of hang out for a couple of weeks, which in theory would pull the isoamyl
acetate and other compounds out of the banana.
This kind of smells good.
Uh, but it does not smell identical to a banana Laffy Taffy.
Maybe like a banana Laffy Taffy spiked with vodka.
So the next step is to send all of these banana essence samples off to a chemist who has the
right equipment to analyze what compounds are in them.
Dr. Curtis Pulliam is a chemistry professor at Utica college in New York.
And thankfully, he's going to help us out.
I'm going to number the samples so that Dr. Pulliam is blind to what sample corresponds
with what banana variety.
He's going to be using gas0 chromatography, mass spectrometry, or GCMS to figure out what's
in our sample.
Gas chromatography separates different molecules.
Then mass spectrometry or mass spec, shoots electrons at the molecules, turning them into
ions.
Those molecules can be separated by mass.
And in the end, hopefully you get a visible signal telling you the mass of those molecules,
which then can be compared to the signals for other molecules.
So you can identify isoamyl acetate by comparing it to the known signal for isoamyl acetate.
We got the results!
And first I just have to say Dr. Pulliam, thank you so much for all the work you did
for us.
These were challenging samples.
There were a lot of compounds that Dr. Pulliam had to weed through, but he's a pro.
So he was able to zero in on this area of signal or peaks where isoamyl acetate might
be.
And it does pop up a compound, which has the chemical name of isopentyl alcohol acetate.
That is, in fact, the ester, which we've been calling isoamyl acetate.
That is the banana flavored ester.
Dr. Pulliam analyzed about 30 samples for us.
And he compared the isoamyl acetate peak in all of the samples that tells you roughly
how much isoamyl acetate was in each.
So what did he find?
The two types of bananas that had the most isoamyl acetate were the Gros Michel and the
cavendish.
So the Gros Michel does not seem to have more isoamyl acetate than the cavendish.
To me, that's surprising because when I tasted the Gros Michel, I felt like it had more of
a banana Laffy Taffy aftertaste, but most of the team thought that the Gros Michel tasted
identical to the cavendish banana.
And I have to admit that these results, at least in the case of isoamyl acetate would
back them up.
Whatever.
But this raises another question.
If isoamyl acetate is in both the Gros Michel and the cavendish, then why did most of the
team think neither of them tasted like a Laffy Taffy?
I guess I'm the only person I'm actually with a sophisticated enough palate to notice that
the Gros Michel tastes a bit different from the standard cavendish.
All of the samples had a bunch of compounds, some or all of which may have masked the smell
and taste of isoamyl acetate.
What I also found interesting was that most of the bananas tested had no isoamyl acetate
at all.
So my gold standard for banana flavor, isn't actually detectable in a bunch of banana varieties.
Unexpected?
Maybe.
A little bit confusing?
Yes.
And yes, but really that's just science.
It's often unexpected and confusing when you're first trying to answer a question, especially
when you're working with samples as chemically complex, as extracts from living cells.
So if you're a chemist and you are dying to know if there's actually a difference between
the Gros Michel and the cavendish, not just in terms of isoamyl acetate, but maybe some
of those other compounds, definitely feel free to pick up where we left off and let
us know how it goes.
If you want to dig deeper into Dr. Pulliam's preliminary results, we've included a link
to them in the video description.
There's some cool stuff in there, like data showing that one of our Gros Michel samples
had something called for furfuryl alcohol, which apparently can have a bit of a burning
odor, which can mask or change the banana fragrance.
Check it out.
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