What Makes Gum Chewy? | Ingredients With George Zaidan (Episode 5)
What's in gum that makes it so chewy? How does this chewy stuff work? And can I make it from scratch?
Inside your ingredients, chewing gum is one of the weirdest things we put in our mouths. I mean, think about your mouth for a second. Your teeth are harder than bone, iron, or steel. Your jaw muscle, the main one, is one of the strongest in your entire body, and your saliva has enzymes in it that start digesting food before it even gets to your stomach. But all that, which has no problem breaking up almost any other food, is basically useless when it comes to gum. I mean, yes, the flavor is gone in minutes, but the gum itself that stays chewy for a long time? I don’t even know how long because there's no Guinness World Record for it. I know that I've been chewing this piece in my mouth for like 20 minutes, and it's totally fine.
So what the hell is in gum that makes it so magical? Every single one of these gums has an ingredient called gum base, except it's not one ingredient; it's a catchall that the FDA allows manufacturers to put on the label to hide the ingredient or ingredients that they're actually using. Presumably, this is to prevent corporate espionage. So if you actually go to the Code of Federal Regulations and look up what's allowed to be in gum base, which I did, you'll find a slightly intimidating list of 46 different ingredients, which seems like a lot until you realize that the FDA does not limit manufacturers to just using one of those ingredients.
So let's do a little bit of math. The 46 ingredients are divided up into five categories with 20, 8, 13, 2, and 3 ingredients respectively. Now, let's assume that manufacturers will only choose one ingredient per category. That gives us 12,480 combinations. But it's actually more than that because manufacturers do not have to use every single category. So the bottom line is that those two little words on the pack of your gum, gum base, can legally refer to 31,725.
Why are there even 46 different ingredients to choose from? Well, basically it's because people have been chewing stuff for a really long time, and we get really creative about what we chew: frankincense, mastic, chickle, and spruce tree resin, to name a few. People have also chewed beeswax and paraffin wax.
So what is all that stuff chemically? Well, frankincense, mastic, spruce tree resin, and chickle (hence the name chicklet) are all tree resins. They come from different species of trees, and chemically they're mixtures of two sets of molecules called terpenoids and phenols. Terpenoids in particular are responsible for some of the most dazzlingly diverse stuff in nature, like that delicious Christmas tree scent or the carotene in a carrot or lanosterol, the granddaddy of all steroids. Now, all terpenoids are made from a five-carbon building block called isoprene, and they're classified by how many isoprene units they have. So, hemeroids have one isoprene unit (or five carbons), monoids have two isoprene units (or ten carbons), and so on. Somewhat arbitrarily, we stop carrying at about nine, so anything with nine or more is called a polyturpenoid.
The most famous polyturpenoid is CIS polyisoprene, also known as natural rubber. And yes, this is one of the ingredients that the FDA allows manufacturers to put in gum base. So does that mean that we're all just chewing sweetened rubber bands? The answer is no for two reasons. First, rubber bands and other rubbers like car tires are vulcanized, which is a process that deserves its own episode; gum rubber is not. But second and more importantly, even though manufacturers are technically allowed to use natural rubber in gum, my guess is that they probably don't or don't use very much. Instead, they use synthetic polymers like styrene-butadiene, polyethylene, or polyvinyl acetate because either they're cheaper or the supply doesn't dry out. But you know what? That is a total and utter guess because, FDA, thanks guys!
On to waxes. Beeswax is the spiritual mother of all waxes, and paraffin wax is made from petroleum. Now, chemically, waxes are different from both resins and polymers. They're mostly long-chain alkanes, alcohols, and esters similar to what you might find in a candle. Now, as you can imagine, every one of these resins, polymers, and waxes has their own specific taste and texture, which is what explains the difference between this kind of gum and bubble gum or bubble gum and this. Incidentally, genius piece of marketing: let’s put gum in the same package as medicine to make you think it’s good for you! Well done!
Anyway, all these resins, polymers, and waxes are pretty chewy, can't really dissolve in water, and aren’t broken down by amylase, the enzyme that's in your saliva. So that's why you can chew gum for such a long time.
So now that we've unraveled the mystery of gum base, I'm going to try and make my own from scratch using only natural ingredients. It's going to be trial and error, and my trial is going to be really simple. I'm going to use mastic gum, which comes from the mastic tree, and beeswax to soften up the mastic, which on its own is sort of tough and sticky. I'm going to use soy lecithin to try and keep these two guys together. So let's do this and see what happens.
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All right, let's give this a shot. Mmm... I think it tastes really good! It's chewy. Getting into it starts off quite hard, but then once your saliva starts to get in, oh my God, hey, this is working! I don’t believe this—I’m chewing gum right now!
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Guys, nice and stretchy, and it's not sticky! See, it looks just like gum! I guess I shouldn't be that surprised because people have been chewing mastic for a long time, but normally when you chew mastic, it's really sticky. This is the beeswax that really softens it up. I don’t mind the taste; could use a bit of sugar, but we'll do that in a different episode.
Anyway, so if you have ideas for a better recipe, or you want to, you know, whatever, just hit me up. I'm on Twitter. This is amazing! Incredible!
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