Whether it’s ice cream, chocolate, candy,
cookies or cake, we like our sweet stuff.
But have you ever thought about
why you have that sweet tooth?
Turns out, it’s all about evolution.
Let’s hear more from this gentleman...
In a tie.
“The Reason is that in nature, foods
that are sweet are incredibly rare,
but they’re a great source of energy.
Sucrose is a carbohydrate. As is glucose,
fructose, etc. Carbohydrates are molecules
that contain an awful lot of energy.
So mammals, whenever they found a source of
carbohydrates, ate as much of it as they could.”
Now we’re not running away from sabretooth
tigers and walking miles for food anymore.
But what makes these foods taste,
you know, sweet?
To be sweet, a molecule has to have three
very specific chemical features that
form a triangle of just the right size.
Here is how sucrose, or table sugar,
fits into the delightfully name 'sweetness triangle.'
Scientists have different ways of
describing this interaction, but
one way is like a hand in a glove.
If the molecule in your food or drink
and the receptor on your tongue
fit together, your brain gets
an electrical impulse that says
“sweeeeet.”
“But what about artificial sweeteners?
“our diet-sipping soda viewers ask.
The granddaddy is saccharin, which was
widely used during world war one when
sugar was strictly rationed.
It’s still around today as “sweet –n– low”.
And it’s in tab. Remember tab?
By the 80s artificial sweeteners went big time
with aspartame, you’ve seen it marketed as
“nutrasweet” or “equal”, and it is almost
certainly in your favorite diet soda.
But here’s the funny thing. Aspartame doesn’t
look anything like table sugar, or sucrose.
“Now, aspartame, as a molecule,
isn’t even close to a sugar.
It’s in fact a tiny little protein.
It’s the addition of aspartic acid and
phenylalanine, known as amino acids,
this means that aspartame is chemically
more similar to meat than it is to sugar.”
So artificial sweeteners taste sweet because
they fit into the sweetness triangle.
But only part of the aspartame molecule fits.
Chemists have since created or discovered
other molecules like sucralose, and stevia,
both of which are sweeter than aspartame,
and hundreds of times sweeter than table sugar.
So that’s why things taste sweet.
Hey, you know what else would be sweet?
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