Wolfing Down Food Science

Iconic Crunch and LOUDNESS (S2: E6)

October 22, 2021 Paige Season 2 Episode 6
Wolfing Down Food Science
Iconic Crunch and LOUDNESS (S2: E6)
Show Notes Transcript

Texture is iconic.  It's why we love some foods and reject others.  Texture is vitally important to make gluten free and meatless meat products acceptable to the general public.  One of the ways we get to these textures is by forming long fibers or by adding air to make puffy products.  One thing that may get missed is that texture can make foods LOUD. Humans tend love loud foods and crinkly packaging.  Find out about the iconic structures that form the foods you love.

Got questions or comments?  Email us!  wolfingdownfoodscience@gmail.com



Wolfing Down Food Science. 



Hello, everybody. Welcome back to Wolfing Down Food Science. So today we're going to continue this discussion about texture. And we're going to talk about these iconic structures in food. 

Now, why do we want to do that? It's not super interesting, in terms of just the basic science, until you think about the fact that we're making so many different products that are like traditional ones, in the sense of, for instance, meatless meat. 

We're taking many different types of plant proteins or yeast proteins, and we're converting them into some kind of meat-like product, even with texture. And things that will even-- for instance, you can make a hamburger that looks like a rare hamburger inside after it's cooked. It sizzles. It does everything a hamburger is supposed to do. And it has the right texture. 

Gluten-free products-- same idea, so in the past, gluten-free was like, eww, texture is not so great, flavor's OK. Now, texture's great, flavor's great, how in the world did we do that? How did we make gluten-free cookies that seem so similar to traditional cookies, or gluten-free bread, or whatever? 

It's getting better and better. The only way that we're able to do that is we're able to make similar structures out of really different ingredients. 

What are some of those structures? 

Well, I think the basic structures that we're dealing with would be things like glass, or crystals, or gels, or emulsions, or foams. There are about five different structures that we deal with in food. And that we're able to use all those basic food ingredients-- carbohydrates, proteins, and lipids, and water, of course-- to build those structures out of those basic ingredients. 

So it's interesting to think about how you approach that. So I think in the past, people have taken vegetable proteins and made them into a veggie burger, for instance. So they weren't really altering the structure of the proteins and how they created that texture. 

And now, with the advent of Beyond Meat, and Impossible Foods, and those things, they're really looking at the protein itself and trying to notice the texture difference, or the protein structure differences, and make them less different. 

So they're really, almost, taking it from a macro-- or micro scale level and trying to replicate it. Instead of, let's just mix some bunch of ingredients together and see if we can get some similar. So it's really cool. 

Yeah. It's like if I eat something at a barbecue or if I eat some kind of meat, I just expect, afterwards, I'm going to have to floss. 


Something-- because of those fibers, something is going to get stuck in my teeth somewhere. I better have some floss. So from my perspective-- this may sound really weird-- but from my perspective, what I would want from a meatless burger, or a meatless meat, is something where after I eat this, I have to floss. Because that is the texture I expect, that fibrous texture to be present in these type of products. 

Yeah, exactly. And tofu doesn't have that, right? And that's your classic soy plant protein that everybody started out with. And now they're starting to incorporate things like pea proteins and different things like that. But the actual structure of the protein, itself, is very different in purpose. 

In a muscle where you're trying to create structure within it to withstand all of this activity that you're doing with the muscle-- walking, and running, or whatever you're doing as a cow, and/or chicken, or a pig, or whatever-- so the structure is very fibrous, in and of itself. 

But a soybean doesn't really do a whole lot of that. So they're more functional proteins within a biological system. And so they're more globular or round shaped versus these fibrous meat proteins. So food scientists have had to take those globular round things and make them look more like the fibrous meat proteins than they were before. And they've done that with processing, which is-- it's just amazing what a good job they've done with it. 

That's a really good point, Paige. I think the idea that the basic structures of proteins, if we boil it down, really, can either be long and fibrous-like strings-- that stuff that gets stuck in my teeth every time I eat some kind of a meat product. 

Or these structures that are more like spheres or more like round materials and that will not have that structure that we expect from a meat product. They're just not going to hold together like that. 

Not unless you do some fancy processing stuff. [LAUGHS] 

It's amazing to, also, realize the difference in flavor that you get. The flavor profile could be the same of these globular versus striated proteins. But it makes all the difference in how you perceive that flavor. 

And I'm thinking about how that is, why that is. Is it because of the surface area of these proteins? There's a difference in how we break them down and therefore, how we taste them? 

Well, I think part of this relates to particle size, things like powdered proteins. So some of the things that we do with protein is to isolate it and basically, pull it out of it's natural matrix, could be soy, could be peas, could be lentils, or yeast, or what have you. 

And then we take that, and we concentrate it in this powder form. And I'm thinking about this because a few years ago I was helping to run a study where we were trying to compare the effects of whey protein and soy protein on, basically, the ability to build muscle and reduce fat. 

And what we were trying to do is, basically, feed different groups soy protein and whey protein. And then switch them up. And the issue was that even though we didn't tell our participants what they were, they could tell that there was one protein powder that was kind of gritty and just never mixed into anything. 

And then there was this other protein powder that was just free-flowing and almost like talc, like talcum powder. And so they knew there was a difference, even though we didn't say, oh, this one is the soy, and this one is the whey. 

But we knew that they could tell the difference. So it wasn't like we could completely keep them from understanding that they were getting one treatment versus another. So I think part of it is that just the particle size, the way that these proteins hold together as powders. 

Well, and once you take them to a powder, all of the processing that has to happen to make them a powder alters the flavor. So sometimes you can get a big sulfur component to that because of the heat and the reactions with the sulfur containing amino acids in the proteins. Like soy has, classically, had this kind of bean-y flavor that a lot of people object to. 


I think pea protein is kind of in it's infancy compared to whey and soy protein processing techniques. And so that whey and soy industry has done a lot to minimize those negative flavor attributes and really make-- and texture, as well. 

Because that's-- a lot of times I'll find protein powders to be gritty because they don't solubilize very well. But that pea protein is coming along with that. They've got some work to do on that. But that's a relatively new protein source on the market so-- as far as concentrated protein powder. 



Well, I did mention flossing a while back. We were talking about my expectation of a burger, or a chicken breast, or some kind of barbecued material. One of the things that I think is important to understand is how we get from those globular-- those sort of spherical shapes into fibers. And one way we do this, and kind of relating to dental health, is called extrusion. 


And extrusion is this idea of forcing materials through a very small opening to produce a shape. And hopefully, you do this at least twice a day-- and that is brushing your teeth. And specifically, the extrusion part is when you squeeze the toothpaste tube and you get this little cylinder of toothpaste. That is an extrusion event. So we do a lot of those in food systems, not with toothpaste, but with food ingredients. 

And we can take those food ingredients and sometimes heat them. And we can actually make long fibers, or strings of material, and put those together into something that then is going to resemble, say, a natural meat product with fibers. 

Just a little smaller than your toothpaste. 



Just a little. 


Yes, not quite that big-- 


--in terms of the fiber size, but yes. 

[INAUDIBLE] protein. 


So when you say that I imagine a hot dog being made-- you know how they-- it comes out of the tube all mixed up. But are you saying that that process can happen on a more molecular level and you-- what's the term called? Extrude? 



OK. And you extrude individual fibers? 

Yes, well, if you think about what a spider web is-- so in our basement, we're constantly trying to get rid of the new spider webs that have just appeared. So what that material is is something that is a liquid, originally, in the spider. It's a protein that's a liquid. When it leaves the spider, it becomes a fiber. And so you can have this extrusion event occur. 

And it produces the fibers that create these pesky cobwebs in our basement. So those are very thin fibers that are extruded, as opposed to that toothpaste example. But it all gets to, basically, forming this fibrous material-- or this cylinder of material if it's larger-- from something that is a mix of other materials. 

And usually, with proteins, heat is often involved in how they are interacting with each other to form these long, fibrous, extruded products. So you can do extrusion cold or hot but with proteins. If we're looking to create a different structure, oftentimes heat is part of that process. 

But you can also add air to structures, too. So that can be a lot of fun, especially if you like cheese puffs. That's an extruded product, or Rice Krispies, or-- 


--any of those things. 

That's interesting. So it's extruded with air? 

Yeah, it's the pressure difference, so on one side before it goes through the little hole, or whatever shape you're making, it's higher pressure. And so when it moves through the hole, it's lower pressure and all that gas expands once it comes through. And so it, in a very fancy scientific term, puffs. [LAUGHS] 



Yeah, so if you can think about the idea of having this dry mix and adding some liquid to it and then pushing it through a tube, that's where you get-- that's where you start that process of extrusion in food. And that could be, say, a cereal mix. That could be dog food. That could be all types of things that you're trying to make, ultimately. 

But once it's in that pipe, or that tube, where you're actually mixing this material into a dough, if you will, you can heat that. And because the tube itself is sealed, it's just under tremendous pressure. 

So now, it's moving through this tube. And when it is released through that small opening, that pressure also releases. And so that's where we get that-- 


--cool kind of puff action is-- 


--when that happens. And so if you think about Cheerios, and Fruit Loops, and all these other wonderful cereals, if you have a shape and you're pushing this shape out through this donut kind of confirmation and you have something that's slicing-- slice, slice, slice, slice-- you can imagine how we make all these little, tiny donuts that are in your cereal bowl. 

That's extrusion with the idea of, basically, chopping this material. Instead of a cylinder, we get these mini donuts, essentially, which I love in my cereal. 

It reminds me of the Stay Puft Marshmallow Man in Ghostbusters. I'm probably really dating myself. 


But marshmallows are an extruded product, as well. So you get that puff action, as well there. 

I think that's a really-- 

We came back to s'mores. [LAUGHS] 

Yes. Well, I think that's a really cool segue because the idea of anything being puffed in this air or other gases that are stuck inside of a cheese puff or inside of a marshmallow-- this is a foam. So this is one of those other-- this is one of those structures that we were talking about. 

So the idea that you're taking this structure and now filling it full of air or some other gas, like for instance, with ice cream-- a frozen foam which I love-- with ice cream you can use air or you can use nitrogen. 

And all of those air bubbles that are in there, then make for this wonderful, foamy texture-- frozen foam texture of ice cream. So there's your foam, whether it's cheese puffs, or Cheerios, or marshmallows, or ice cream. 

I have never thought of ice cream as a foamy texture up until now. Isn't it all just this liquid that gets frozen? 


The churning aerates it. And in fact, the FDA has limits on the amount of air-- if you're an ice cream producer-- has limits on the amount of air you can put into your ice cream. Because air is free. 



You could put a whole lot of air in there and really decrease your costs. [LAUGHS] So there are some limits by the Federal, or the FDA, that limits the amount of air you can put in. 

I wonder if these low calorie ice creams-- I know one brand called Halo Tops that are very light and fluffy. And I wonder if they have extra air put in them or how they get that very light, whipped ice cream? 

OK. So Teresa, I have a homework assignment for you. So here's what you do-- go to the grocery store and start at the section where they have all the pints and get the super premium, get the super premium ice cream. And then find a pint of the cheapest ice cream you can possibly find and compare the weights of the two. 


Same volume, different weight. 



Think about how much lighter that cheaper ice cream is and it's the idea that-- the term-- since we're starting to talk about some of these terms, the term that we would use in the ice cream world is called overrun. So overrun is how much air that you're pumping into this ice cream mix as it's freezing to make this frozen foam. 

So if you think about the ultra premium ice creams-- like you think about Haagen-Dazs, and you think about Ben and Jerry's, and of course, what I think about more than anything else, Howling Cow, obviously. If you think about any of these ice creams, they are lower overrun. So you don't put as much air into them. And for that reason, they are heavier. They are thicker. 

And from my perspective, if you buy a pint right out of the freezer, they are spoon-bendingly good. You can literally bend a spoon with some of these flavors just trying to get the first little bite out. It's so thick. And it's heavy. It feels heavy relative to it's volume. If you go the other direction, you'll get something that feels super light. And your spoon doesn't have any problem going through it. 


Because it's going through lots of air. So there's not a whole lot of resistance. So that's going to directly affect this texture, on the one hand, super creamy, very heavy texture, very rich texture. The other one is much, much lighter. And it's just going to melt right away on your tongue just because it's more air. It's more overrun. 

That's so funny because Halo Tops are advertised as being light and being fluffy. And in reality, maybe, they just put-- 

It's a definite way to decrease calories. [LAUGHS] 

Yeah, definitely. 


There's some other stuff going on in Halo Top two with ingredients to help that. [LAUGHS] But definitely, if you-- because the-- what was it? Yoplait Whips? That was that whipped yogurt that they came out with. I don't know if that's still on the market or not. 

But that was on the market, and I always thought, man, that was a great idea. Let's put this free ingredient, and change the texture, and have a totally different experience, and it's lower calorie. [LAUGHS] I just thought that was genius. [LAUGHS] 

They do that with cream cheese, too, I believe. 

Yeah and it helps with the texture for spreading, too. So it's multipurpose. [LAUGHS] 

Absolutely. And I think whipped butter-- same thing, same idea, it's just easier to spread. If you've ever had that experience where you have real butter that's real cold, when you try to spread it across a roll, it just tears it up. It just really-- it just doesn't work until that butter is kind of warm. Yeah. But the whipped butter, I mean it just really lets the knife cut right through it because part of what you're cutting through is just air. And cream cheese-- yeah, that's a great example, Caitlin. Cream cheese is a great example of that. So there are reasons to do this. There are really good reasons to put a lot of air into a product. And that's one of them-- is just spreadability. 

It definitely is. 

I just think it's funny that they advertise it as-- in big headline like, light and fluffy, buy this product. But reality, it's just cheaper for the producer to make a new product. Do you think that canned cheese or sprayable cheese is an extrusion? 


That's another product, right there. 

Definitely extruded, yeah. Yeah. So I guess it would be extruded. And I don't know-- 

That's a customer extrusion. 


The customer is extruding that product-- 


--versus the manufacturer. [LAUGHS] 

Extra experience. 

Yes. And of course, we can't forget about whipped cream in a can. 

Oh, yeah. 

You know, this wonderful material that is-- I mean, you are extruding it. But you're extruding a foam, so that shape that it will produce on top of your strawberry shortcake or whatever it is that you're putting on top of it. But that's definitely a foam, as well. So-- 

That's a different gas, right? That's nitrous oxide. Is that right? 

That's nitrous oxide. 


That's nitrous oxide. So, yes, that's a different one, yep. And that's a whole story. There is literally, I mean literally, a study to figure out which gas is going to make the best whipped cream in a can. I mean, it may seem like this can't be that hard. You put whipped cream in a can with some compressed air, and that's it. 

Out it comes, yeah. 

That's what I thought. 

It didn't work. It didn't work. So it took a lot of research, actually, to figure out which gas was actually going to do the job. There's a reason why nitric oxide is used in those canned whipped creams instead of just air. 

It so often is true, what seems simple on the surface is [LAUGHS] more complicated beneath. 

Realizing that for a lot of things regarding food science, it just is so convenient that we can go into the store and pick up this beautiful, gluten-free cookie for me, for example. 

But to think about how much food science and research has gone just to get the texture right, not to even mention the flavor, is really admirable. And it's great to see how long it's come as well, especially for gluten-free industry. 

[LAUGHS] Yeah, I think any time you're trying to mimic a pre-existing thing with something completely different, it's a challenge. There's a lot of development that has to take place. 

To speak on that, I know gluten-free manufacturers are starting to use tapioca. Or maybe not starting to use, but they do use tapioca flour and a lot as a substitute for breads and pastas. And I find that it is one of the best products because it offers this squishy, kind of palatable experience. 

If you can think of tapioca balls in your boba tea, it's giving that same elasticity that you don't get with a lot of other gluten-free products. Let's say, corn base or rice base is very crumbly. 

And I think that has been the main base for gluten-free products for many years. And now, I've noticed that different proteins are starting to be used, which is very exciting to see the perfect mixture be derived. 

And that gets to forming those networks. As you mentioned, in the boba tea, just those wonderful pearls, when you bite into them it does take some effort. And they hold together. You have to kind of chew them up a little bit. They fall to pieces, instead of just-- they don't shatter. They don't just disintegrate. They actually hold together. 

They stick to your teeth a little bit. 

Yes. Yeah. Yeah. 

I think we-- a lot of times with texture, we overlook how we break it, whatever that food is, how we break it down in our mouth. If it adheres to our oral surfaces and then how it reforms before we swallow it. Because we are all-- our mouths are meant to break down this product to a size where we're not going to choke when we swallow it. Or something that's flexible enough to be swallowed in the correct size. 

So I think it's really key with some of those things, like you were saying, Teresa. Crumbly and it's not supposed to be crumbly. Or it really sticks together in your mouth, and it's not supposed to do that. Or it is supposed to do that, and it doesn't, so-- all of those are really tough aspects to try to mimic. 

It screams just as loud as if you were to eat some spoiled food, some sour food. You're like, oh, my gosh. This is wrong. Your body says, don't eat this. 


This is wrong. 

Yeah, I got to say I had a perfectly good protein bar yesterday. And the flavor was good. And everything was good about it, except for the fact that it completely hung on to my teeth. I mean, when I was chewing this thing, the entire surface of my teeth, it felt like, were just covered with this protein bar. And it did not want to let go. 

And so we call this tooth packing-- the idea of, this stuff is really stuck between our teeth, or whatever. And to me, that texture is something that I don't really like. And so I liked that protein bar right up until that moment. And then I was like, uh, no. It's just-- it's too much. It's too much. I should not have-- I should not need a squeegee to get this stuff off of my teeth. 


It should be a little bit easier than this. It's just not leaving. So yeah, so it's interesting how much that texture, the ability to stick to your teeth, really affects the sensory experience and from my perspective, not in a positive way. 

We have a neighbor who is getting her braces off. And they went to the grocery store and found all the stuff that she couldn't eat with braces. So it was all the stuff that sticks to your teeth. [LAUGHS] So it depends on your oral surfaces, too, at what you can and what you like. [LAUGHS]. 

We need an anti peanut butter toothpaste to have some release of the peanut butter. I don't know. It encapsulates your mouth. It is completely overwhelming But it's so good that I don't care. 

Wait, I have an idea. So all you need to do is take some of that Pam cooking spray and-- 


--right before you eat one of these things, you just open your mouth and spray Pam inside. And then you can just eat whatever you want. And it'll just slide right off of your teeth. 

That's right. 

So there we go. So now I have something new to try today. 

Make all your teeth super hydrophobic with oil. And then all of those water things will just slide right off. 


Don't try this at home, kids. 





All right. And now for our new segment called, "Can You Hear the Texture?" We're going to try some everyday foods and just see if you can identify what these things are just by their sound, all right? Are you ready? So let's-- 


--see if-- 

Let's do it. 

--[inaudible] hosts can identify what these things are just by the way that they sound. So here we go. 


Sounds kind of vegetable-y. 


Does that work? 

Celery, maybe. 

Hey, Caitlin, you got it. That's celery. Ding, ding, ding, ding. That's celery. 

Way to go. 

Yeah, very nice. So all right, second one, here we go. You ready? 


It's like celery, but soft. Like lighter, less things to crunch. But still the crunch is there. 

Like a snap pea? 

That's a good guess. 

That-- yeah, I think that's a pretty good guess. That was a baby carrot. 


That was a baby carrot. 

That was the-- wow, celery is so much louder. [LAUGHS] 

Yes, celery is really a loud food. All right, let's switch to a different type of food. See what you all think about this one. 




Are you eating it or opening it? [LAUGHS] 



Now he's eating it. 


I'm getting like a wetter type of crunch. 


Tortilla chip? 

Very good. 



I like this one because it's a loud food in a loud package. 

So you were opening the bag? Yes, yeah, [INAUDIBLE]. 

It's part of the auditory experience. 

I think, so I'm not a-- I'm not a marketing person. And I don't really work much with food packaging, per se. But I do sometimes wonder why loud foods are in loud packages. It just seems like that they go together somehow. So yeah. 

That's a true observation. 


All right. If we can get-- 

Opening the package. 

Now, that was closing the package. 

Oh, OK. 

Let me see if I can get another one here. 






Can we hear it again? [LAUGHS] 

I don't know if I can reproduce this one. That was Rice Krispies. 

Oh. It was too soft. 

Yeah, that was Rice Krispies. 

Was it popping in the milk? 




You will definitely have to get that one on recording. That's a good one point for Dr. Harris on that one. 

OK. We'll try one more here. 



I'm getting like a cookie or-- 


--easily breakable food. 

It is pretty easily breakable. 

[INAUDIBLE] hints? 

It's not a cookie. 

Is it a starchy food? 

Not starchy. 

Not starchy. 

Kind of salty and savory. 

But not starchy. 

Peas? [LAUGHS] I don't know. 



That was peanuts. 

Oh, nice. Yeah, that one was easily breakable. You can tell that it was softer to chew. I have a fun one. 

All right. 



That's the bottom of your drink. 

Yep. Yes. The texture is-- 

That's that noise that drives my daughter crazy. [LAUGHS] 

OK. Well, I have one for you, as well, here, Teresa. Ready? 



A can of some sort. 

You're opening some soda. 

A carbonated beverage. 

Yes. Yep. 


All right. 

I'm on the scoreboard. [LAUGHS] 

That was-- 

All right. 

--that was easier and harder than I thought. Does that sound weird? [LAUGHS] 

No. Well, I like the fact that you could tell the difference between levels of crunch. You could tell the difference between a baby carrot and celery. Because I think that might help us with this conversation piece. Why is celery louder? Why does it snap more? And why are you able to actually tell some of these sounds and others you can't? 

So I was kind of thinking just for fun, maybe we'd have to have all these, definitely-- these foods with definite sounds, or packaging with definite sounds that you could identify, or the opening of a can, or what have you-- and then others, just for fun, that were silent just for the comedic effect. Like, you can't tell what that is? Yeah, just-- that we're just [INAUDIBLE]. 

We're trying to see if you can hear this at all. I don't think so. It's a little foamy ball. How do you-- 

[INAUDIBLE] red noses things. 

Oh it is. 


There we go. 

Do you just have that laying around? 

I can't do it now. 

Yeah. If we did one episode entirely with those noses on, then I think we could talk about sense of smell. Maybe that's in another season, since this one's really texture. But I could just imagine the entire episode-- 

I would love that. 

--just [INAUDIBLE]. 

Very nasally. 

That one would have to be published as a video podcast. 


Content [INAUDIBLE] be best. 

Yep. I'm just thinking about Doritos, potato chips-- all these things come in really loud packaging. And there was actually one-- believe it or not, this is true. There was one packaging that was so loud it was canceled. And that was Sun Chips. 

So there was-- the idea was to have a packaging that is completely biodegradable. And they did it. And so we had these wonderful baked chips inside of this package. And the package was so loud that it just-- 

They received too many complaints. 

It-- yeah, not even for those who like loud food, and I do think that's a thing. I think there are some who like loud food, so yeah. 



Open mouth eaters like loud food. 

Yes. Yes. So I have a few adolescent open mouth eaters at home that we're trying to persuade that's probably not the best thing to do. 

Don't give them Sun Chips. 


I hope they keep up with the biodegradable effort, though. That sounds very cool-- 


--to get chips in there. 

I would just like candy wrappers that are silent, you know. 

Oh, gosh. 

I would really like candy wrappers that are silent. Because I know-- 

Movie theater purposes? 

Well, that's a thing to me in meetings. Like sometimes we'll be sitting in a meeting, it could be at work or it could be at church or something. And it's very quiet. And then somebody-- thinking, well, this is no big deal-- decides that they're going to open up a caramel or a peppermint. And it's just completely distracting me-- 

Crackle, crackle, crackle. 

--from whatever is being said. I'm completely derailed by this little, tiny package of a peppermint. And, yeah, and maybe-- 

There's one person at our church every Sunday-- the sermon starts, and he starts [IMITATES UNWRAPPING CANDY] unwrapping the candy. 

Yeah, I was going to say-- maybe I'm only-- I'm the only one. But it really can completely just derail my train of thought, just that little [INAUDIBLE]. 

Raise awareness for loud candy wrappers. 

That's right. That can be your cause. 


There we go. It just-- it makes me think about the next State of the Union Address. The President is giving this big speech and then right behind there you have the Vice President and the Speaker of the House. And they break out the candy. And the president is like, would you mind? 

That would be an SNL skit, right there. That would be the best SNL skit. 

That would be hilarious. Yes, [INAUDIBLE] has to see that. So anyway-- 



If you'd like to find out more about our podcast, Wolfing Down Food Science, please check us out at NCSU's Food Bioprocessing and Nutrition Science website, where you can find our show notes, reference links, and more. You can find out more about NC State, our department, and FS 201-- the amazing course that has brought us all together-- on our website, as well. 

Please don't forget to subscribe to Wolfing Down Food Science wherever you stream your podcasts like Spotify and iTunes. Thanks for tuning in to Wolfing Down Food Science. See you next time.