Speaker 1: Get in text technology with tech Stuff from how stuff
Speaker 1: Works dot com. Hey there, and welcome to tech Stuff.
Speaker 1: I'm your host, Jonathan Strickland. I'm flying solo today and
Speaker 1: I'm going to talk about something that I thought was
Speaker 1: really cool. I actually learned a lot in the process
Speaker 1: of looking into this. A few weeks ago, I covered
Speaker 1: a story for How stuff Works Now about a technique
Speaker 1: to make melted chocolate less viscous so that it flows
Speaker 1: more freely through manufacturing equipment. So a couple of things.
Speaker 1: First of all, How stuff Works Now, if you aren't familiar,
Speaker 1: is our more news oriented page, So if you go
Speaker 1: to now dot how stuff works dot com you can
Speaker 1: see it. We have a lot more stories that are
Speaker 1: reflective of things that are unfolding now, thus the name,
Speaker 1: and we also do video for that. There's also a
Speaker 1: podcast hosted by Lauren Vogelbaum. You can subscribe to that
Speaker 1: house Stuff Works Now. It's a summary of some of
Speaker 1: the stories that we cover each week. So if you're
Speaker 1: not familiar with that, go check it out. It's pretty awesome. Anyway,
Speaker 1: I did this story about chocolate and making sure you
Speaker 1: could reduce the viscosity of liquid chocolate so that it
Speaker 1: doesn't come up stuff, because one of the challenges of
Speaker 1: working with chocolate is making sure that it doesn't clog
Speaker 1: up the pipes like Augustus Gloop in Willy Wonka. So
Speaker 1: a consulting firm working on behalf of Mars Incorporated, which
Speaker 1: is giant candy company that makes a lot of different
Speaker 1: chocolate products. This consulting firm went to a group of
Speaker 1: physicists at Temple University, and physicist is one of those
Speaker 1: words I have difficulty pronouncing. I think I might just
Speaker 1: say scientists. Scientists at Temple University. Hey, and that's way better.
Speaker 1: And these guys have developed a method to make crude
Speaker 1: oil flow more easily through pipes using electric fields. So
Speaker 1: the question that the consulting firm had was could you
Speaker 1: do the same thing you did for crude oil for chocolate?
Speaker 1: And here's a spoiler alert, Yeah they could. But I
Speaker 1: want to talk more about what they did and how
Speaker 1: they did it because it's it's a really interesting, uh story.
Speaker 1: So I'm gonna go into a bit more detail about
Speaker 1: the physics and the technology behind the scientists solution for
Speaker 1: this problem. It's pretty cool, and a lot of it
Speaker 1: was stuff I had no idea about before I began
Speaker 1: to research the story. So today's episode is going to
Speaker 1: be about chocolate. It's gonna be about viscous fluids, about
Speaker 1: electro real logical fluids and how an electric field can
Speaker 1: change their fluid I properties, specifically viscosity. So yeah, this
Speaker 1: episode is gonna be science heavy, but there's also chocolate,
Speaker 1: so stick around. You know everyone loves chocolate. So let's
Speaker 1: get into the physics first. Now, fluid dynamics is be complicated,
Speaker 1: and also there's some stuff that's related to this that
Speaker 1: falls into the category of misinformation about viscosity. So I'll
Speaker 1: be talking a lot about not just the principles in general,
Speaker 1: but some specific uh myths that I would like to bust,
Speaker 1: as some of my former coworkers used to do on
Speaker 1: a regular basis. So, first of all, viscosity is a
Speaker 1: property of fluids or semi fluids, and it can be
Speaker 1: described as a fluids thickness or stickiness and its resistance
Speaker 1: to flowing due to internal friction. More accurately, viscosity is
Speaker 1: a measure of the resistance of a fluids deformation due
Speaker 1: to tensile or shear stress. Now, sheer stress is mechanical
Speaker 1: stress that's parallel to the surface of that substance. So, uh,
Speaker 1: you could think of sheer stress as it's not perpendicular.
Speaker 1: It's not like an impact, right, It's more of a
Speaker 1: tearing um ten style stress is a pulling stress rather
Speaker 1: than a compression stress. So again, instead of compressing stuff
Speaker 1: closer together, it's about pulling stuff further apart. And water
Speaker 1: has a pretty low viscosity. Honey has a very high viscosity.
Speaker 1: So we actually measure viscosity in units called poises p
Speaker 1: o I s e s. Water at room temperature twenty
Speaker 1: degrease celsius or so has a viscosity of zero point
Speaker 1: zero one poises or a center poise. In other words,
Speaker 1: a thick oil might have a viscosity of one point
Speaker 1: zero poise. Now we measure viscosity with a viscometer. I'm
Speaker 1: not making that up. It's actually the name of the
Speaker 1: tool used to measure a fluids viscosity. Now, typically we
Speaker 1: will call a liquid viscous if its viscosity is higher
Speaker 1: than that of waters, and if the viscosity is lower
Speaker 1: than that of waters, because water is not the least
Speaker 1: viscous material that we know of. If it has a
Speaker 1: lower of viscousy then water we call that fluid mobile.
Speaker 1: So some fluids are so viscous that they can actually
Speaker 1: seem to be a solid, and this leads us to
Speaker 1: that misinformation I was talking about. It's one of those
Speaker 1: things that I hear bandied about pretty well, not not
Speaker 1: not as frequently as it used to, but it's one
Speaker 1: of those miss understandings that gets passed around its fact
Speaker 1: every now and again. And that is the idea that
Speaker 1: glass is one of these fluids, that glass is actually
Speaker 1: a fluid that is um so viscous that it appears
Speaker 1: to be a solid, and that is not true. Glass
Speaker 1: is not a very, very viscous fluid. It's a little
Speaker 1: more complicated than that. Uh So, here's the basic idea.
Speaker 1: People have noticed that if they look at windows and
Speaker 1: very old buildings like medieval churches, they see that the
Speaker 1: base of the wind is thicker than the top of
Speaker 1: the window. And this has led some people to conclude,
Speaker 1: to jump to a conclusion that the reason why the
Speaker 1: base is thicker than the top is that glass, over
Speaker 1: the course of centuries has been flowing downward and that
Speaker 1: it's so slow that it's not detectable under normal situations.
Speaker 1: It's only over the course of centuries that you can
Speaker 1: see the difference. Uh. Here's the problem is that that's
Speaker 1: just not that's not the case. That's not true, it's
Speaker 1: not what's happening. Uh. If you look at the glass
Speaker 1: making approach in the Middle Ages, you'll see why there's
Speaker 1: a thicker part of the pane of glass. Glass was
Speaker 1: created generally speaking, in the Middle Ages through something called
Speaker 1: the crown glass process. It's pretty neat idea pretty neat
Speaker 1: way of making glass windows. Here's how it we're in general. First,
Speaker 1: you get your raw materials h to make glass, and
Speaker 1: in the Middle Ages that was essentially sand and potash,
Speaker 1: and you mix it together and you melt them in
Speaker 1: a very hot furnace. And then you would get a
Speaker 1: glass blower with a pipe and they would get roll
Speaker 1: out a lump of molten glass, put on the pipe,
Speaker 1: blow out the glass. So they expand the glass outward
Speaker 1: before flattening it, so they don't just you know, create
Speaker 1: a globe of glass, they actually flatten it back out. Then,
Speaker 1: with a flat glass which is still hot and still malleable,
Speaker 1: it hasn't cool to the point where it is really solidified.
Speaker 1: You would put that on a disk, a spinning disk,
Speaker 1: and the disk spins around to draw out the glass
Speaker 1: to flatten it further, sort of like how a pizza
Speaker 1: maker will toss and spend dough in the air in
Speaker 1: order to make that circular pizza. It's kind of similar
Speaker 1: to that. So the disk spins and the centripetal force,
Speaker 1: if you like, is pushing the glass outward toward the edges.
Speaker 1: So then once that's done, you would cut the glass
Speaker 1: into panes so that you could fit them in a window. Now,
Speaker 1: that would mean that when you would get anywhere close
Speaker 1: to where the edge of the glass was, the outer edge,
Speaker 1: because you put the glass on that disk and you
Speaker 1: spun it around, the outer edge was thicker than the
Speaker 1: rest of the glass, just because that's where the excess
Speaker 1: was accumulating as it was being uh pushed outward due
Speaker 1: to the spinning motion. So typically window makers would cut
Speaker 1: pains so that a thicker edge would only be on
Speaker 1: one side, and they put that side at the bottom
Speaker 1: at the base of the window, so glass didn't flow
Speaker 1: to the base. Over hundreds of years, it started out
Speaker 1: like like that. It was like that from the beginning.
Speaker 1: That being said, glass is a really interesting substance. It's
Speaker 1: what we would call an amorphous solid, so saying that
Speaker 1: it's a fluid or a liquid is not accurate. But
Speaker 1: it is an amorphous solid, which is a little hinky
Speaker 1: compared to other materials that you might be familiar with.
Speaker 1: So typically not everything, obviously metals and glass being exceptions,
Speaker 1: but a lot of solids have an ordered crystalline structure,
Speaker 1: so that means the molecules are organized in a pretty
Speaker 1: regular lattice. They form a nice repeating pattern that goes
Speaker 1: throughout the entire material. When you heat up this solid,
Speaker 1: those molecules start to shimmy and shake, some of the
Speaker 1: molecular bonds might start to break down a little bit,
Speaker 1: the bonds between one molecule and another, the essentially the
Speaker 1: crystalline order breaks down, and if you heat a solid
Speaker 1: beyond its melting point, the crystalline structure completely breaks down
Speaker 1: and molecules will begin to flow freely or as freely
Speaker 1: as the viscosity of that fluid allows, and there's a
Speaker 1: very clear delineation between the solid and liquid stages. You
Speaker 1: can see the difference molecularly from the way this substance
Speaker 1: looks when it's in solid form versus in liquid form,
Speaker 1: and we call that delineation that border between the two
Speaker 1: the first order phase transition. It's obvious when you look
Speaker 1: at it from a microscopic standpoint. I mean it's obvious
Speaker 1: from a macroscopic standpoint too, because a solid behaves one way,
Speaker 1: in a liquid behaves another way. Now, when you cool
Speaker 1: a liquid down, its viscosity tends to increase. If you
Speaker 1: introduce a nucleation site into the liquid, crystals can form
Speaker 1: and you get that nice solid structure again once you
Speaker 1: get down below what the melting point was. Uh, but
Speaker 1: glass doesn't do this. Glass doesn't form a crystalline structure.
Speaker 1: Glasses viscosity increases, so it does what other fluids do
Speaker 1: at that point. But since it doesn't crystallize, it solidifies
Speaker 1: in a different way. The molecules actually form an irregular arrangement,
Speaker 1: not that nice ordered structure that you see in other solids,
Speaker 1: but that a regular arrangement is still cohesive enough to
Speaker 1: maintain rigidity. So glass does become a solid, it's just
Speaker 1: not a crystalline solid. It's an amorphous solid. Now, there's
Speaker 1: no first order phase transition here. It's not like if
Speaker 1: you looked at the liquid form of glass and the
Speaker 1: solid form of glass, you would see a massive difference
Speaker 1: in the molecular structure. But there is a second order transition. Now.
Speaker 1: That transition is a little more subtle than first order
Speaker 1: transitions and evolves the thermal expansion and heat capacity of
Speaker 1: a material, So it wouldn't be as obvious to casual
Speaker 1: observation on a microscopic level, but there would still be
Speaker 1: differences with the thermodynamics of the material. Ill, so we
Speaker 1: still would say the glass is a solid not a liquid.
Speaker 1: All right, I'm done with glass now, I promise. I
Speaker 1: had to go on that little track just because it
Speaker 1: was related to the stuff I was talking about, and
Speaker 1: I get really irritated seeing that one myth passed around
Speaker 1: as fact. So now you know, if you ever go
Speaker 1: through a a tour and the tour guide says and
Speaker 1: the reason that the windows are thicker at the bottom
Speaker 1: is because glass flows over the course of hundreds of years,
Speaker 1: you can raise your hand and say, well, actually, and
Speaker 1: tell him Josh Clark sent you, because I don't want
Speaker 1: that kind of burden on me. I like being able
Speaker 1: to take tours anyway. Let's get back to Viscosty in general. So,
Speaker 1: like I said earlier, viscosty is due to internal friction
Speaker 1: of a liquid. And you might think that that sounds weird,
Speaker 1: like how can a liquid have friction inside of it?
Speaker 1: But we're talking about liquids specifically that have like molecules,
Speaker 1: and those molecules can have a tendency to resist getting
Speaker 1: by each other. So some molecules are more resistant you
Speaker 1: slipping by each other than others. Or a liquid could
Speaker 1: actually have particles that are suspended in it. It could
Speaker 1: be a suspension, which is different than just a pure liquid.
Speaker 1: But if it's a suspension, it's got particles suspended within
Speaker 1: the liquid at at some level of density, right, Like
Speaker 1: some maybe a pretty weak suspension where you don't have
Speaker 1: a whole lot, but others could have all a greater
Speaker 1: density of particles inside a suspension of fluid. Make chocolate bars,
Speaker 1: let's say, and you're laying out melted chocolate into the
Speaker 1: mold for the chocolate bars, uh, and it clogs up
Speaker 1: and you have to stop production and clean out the
Speaker 1: clog and get everything back up to temperature and start
Speaker 1: it all over again. It's time consuming and expensive when
Speaker 1: that happens. So one solution to preventing it from happening
Speaker 1: is dilute the cacao more so that those particles don't
Speaker 1: clump up as much because there there's a less dense
Speaker 1: cacao component in the fluid. That essentially means replacing cacao
Speaker 1: with something else, typically something that is less viscous, like
Speaker 1: that oil that fat. Essentially, so you usually add more
Speaker 1: fat to the recipe, so you get the more fat
Speaker 1: but less cacao. However, it ends up flowing better and
Speaker 1: creates the chocolate bars that you want without creating the clogs.
Speaker 1: But it's not necessarily the best product you could create.
Speaker 1: It's just the most convenient based upon the method of production.
Speaker 1: So that's where this alternative solution comes in. If you
Speaker 1: could change the shape of those cacao particles in the
Speaker 1: fluid so that they packed together more effectively, you would
Speaker 1: reduce that viscosity, that internal friction of the fluid. So
Speaker 1: imagine you've got one of those inflated rubber balls, like
Speaker 1: like a kickball or something. Now imagine that you're able
Speaker 1: to grab hold on either side of this ball and
Speaker 1: pull it outward so that you're elongating it. Now it
Speaker 1: would become a more of an oval shape, or as
Speaker 1: the researchers at Temple University called them, prolate spheroids. Now,
Speaker 1: the interesting thing about these prolate spheroids is if you
Speaker 1: align them in the direction of the flow of chocolate,
Speaker 1: you can pack more of them together. They have these
Speaker 1: elongated sides and they will fit together much more snuggly.
Speaker 1: You can create chains of them and chocolate would flow
Speaker 1: much more readily. But how do you change the shape
Speaker 1: of those cocu particles. What is it that you could
Speaker 1: do to make them actually assume a different shape than
Speaker 1: their natural globular ball like shape. This is where electric
Speaker 1: fields come in. Uh, we're gonna talk about applying magnetic
Speaker 1: or electric fields to a fluid to changes viscos. But first,
Speaker 1: this doesn't work with every fluid. Uh. Not every fluid
Speaker 1: reacts to electric fields and magnetic fields in a way
Speaker 1: that will alter its viscosity. But it does work in
Speaker 1: fluids that have certain non conducting or weakly conducting particles
Speaker 1: suspended in an electrically insulating fluid. Now, we call this
Speaker 1: a special type of liquid, electro reeological fluid. Electroheological fluids
Speaker 1: essentially means that when you apply an electric or magnetic
Speaker 1: field to such a fluid, it changes its viscosity. Sometimes
Speaker 1: we also call them smart fluids, but more about that
Speaker 1: in a bit now. Interestingly, the property was completely discovered
Speaker 1: by chance. There was an inventor named Willis Winslow who
Speaker 1: observed the effect in the nineteen forties, and he actually
Speaker 1: patented it in nineteen forty seven. Now, for this reason,
Speaker 1: we sometimes call this effect of changing an electroheological fluids
Speaker 1: viscosity the winds Low effect, And I'll mostly be using
Speaker 1: that term from here here on out, because there's only
Speaker 1: so many times I'm gonna be able to say electroheological
Speaker 1: before my mouth just decides to rebel against the rest
Speaker 1: of me and march out the door. And as entertaining
Speaker 1: as that would be, kind of needed. Alright, So, applying
Speaker 1: an electric or magnetic field to such a fluid changes
Speaker 1: that fluids viscosity within meloseconds like it's practically instantaneous. And
Speaker 1: if you remove the field, the particles in the fluid
Speaker 1: will snap back to their original shape, to the fluid's
Speaker 1: viscosity will return to what it normally would be. So
Speaker 1: the change isn't permanent. It only persists as long as
Speaker 1: the respective field persists, which is super cool because you
Speaker 1: can do these temporary changes that are really useful in
Speaker 1: specific situations and then have it go back to normal
Speaker 1: and it's like it never happened in the first place.
Speaker 1: But one thing to keep in mind is the direction
Speaker 1: of the electric or magnetic field is critically important when
Speaker 1: you want to make a particular effect. So, in the
Speaker 1: case of chocolate, if you apply the electric field perpendicular
Speaker 1: to the direction of flow, you will actually increase the
Speaker 1: viscosity of the chocolate. You will make it thicker, more
Speaker 1: like a gel. Melted chocolate will turn into this kind
Speaker 1: of thick gel. It'll otherwise have all the same properties
Speaker 1: that had before, but that viscosity will increase dramatically. However,
Speaker 1: if you were to apply that electric field in the
Speaker 1: direction of the flow of chocolate, then you would decrease
Speaker 1: the viscosity of chocolate and it will flow more freely
Speaker 1: at that point. Now this makes some sense because imagine
Speaker 1: that you have these elongated ovals, these uh prolate spheroids. Right,
Speaker 1: If you stand them vertically, then you can imagine them
Speaker 1: slipping through a pipe very easily. If you laid them
Speaker 1: out horizontally, you could imagine um ending up like like
Speaker 1: blocking a pipe easily, because it's like trying to fit
Speaker 1: a long stick through a narrow doorway. If you don't
Speaker 1: turn it the right way, you're just gonna hit against
Speaker 1: the door. This is making me think of my dog Tiboalt,
Speaker 1: who has done this on numerous occasions. He just he
Speaker 1: can't get it through his little doggy mind. They needs
Speaker 1: to turn the stick vertical in order to move it
Speaker 1: through a doorway. He just wants to charge ahead full
Speaker 1: steam with the stick horizontal. In many other ways, He's
Speaker 1: an intelligent dog, so we forgive him this lapse of judgment. Anyway,
Speaker 1: the chocolate on a molecular level is essentially the same thing.
Speaker 1: If you are applying this electric field perpendicular to the
Speaker 1: flow of chocolate, then you get this much thicker uh mixture.
Speaker 1: And an interesting side note, the electro reeological properties of
Speaker 1: chocolate aren't a new discovery, right. I mean, I covered
Speaker 1: this story for how stuff works now because there was
Speaker 1: a new application of this property with chocolate. But we
Speaker 1: actually knew that chocolate would react this way already, at
Speaker 1: least to the point of increasing the viscosity, because back
Speaker 1: in there was a Michigan State University grad student who
Speaker 1: observed the Winslow effect on chocolate, and his name is
Speaker 1: Dr Christopher R. Daubert, and as professor Dr James Steph
Speaker 1: worked with him. They both conducted experiments on liquid chocolate
Speaker 1: and observed the Winslow effect. Now, in that experiment, Daubert
Speaker 1: was again increasing the viscosity, not decreasing it, so he
Speaker 1: was turning chocolate into that thicker gel. That the liquid
Speaker 1: chocolate into thick gel. Uh. It wasn't until recently that
Speaker 1: we saw someone try and do the opposite. So that
Speaker 1: brings us to the Temple University experiment. So you had
Speaker 1: these researchers. They had worked on crude oil and decrease
Speaker 1: the viscosity of crude oil, which is a huge thing
Speaker 1: for the oil industry to be able to uh move
Speaker 1: oil more effectively without the fear of clogs or viscosity
Speaker 1: screwing up things that had been planned ahead of time.
Speaker 1: They wanted to see if they could in fact use
Speaker 1: a similar approach to have liquid chocolate move more smoothly
Speaker 1: through a system so that manufacturers could save money by
Speaker 1: not having to worry about cleaning up clogs and shutting
Speaker 1: down production for maintenance. So They had to test this
Speaker 1: hypothesis that an electric field directed in the flow of
Speaker 1: liquid chocolate would reduce viscosity. So they built a cool
Speaker 1: chocolate zapping gadget. That's not really a zapper, that's kind
Speaker 1: of a it's kind of not entirely accurate, but I
Speaker 1: like the idea of using electricity does zap chocolate and
Speaker 1: make it better. That's just a over simplification of what happened,
Speaker 1: But that's okay. I'll I'll explain to you what was
Speaker 1: actually going on. They built this thing where it starts
Speaker 1: with a bit of a melting chamber. You can just
Speaker 1: think of it as like a a pot. It could
Speaker 1: even be a glass vial. Really, it could just be
Speaker 1: any little container that can hold chocolate. They put the
Speaker 1: chocolate in the container and they cover the container, sealing
Speaker 1: it shut. Uh. They added compressed nitrogen gas into the
Speaker 1: chamber simply really to to just increase the pressure inside
Speaker 1: the chamber itself. The chamber was heated so that you
Speaker 1: had chocolate melting into a liquid. There was a thermocouple
Speaker 1: in there to make sure that the temperature was correct
Speaker 1: so that the chocolate would not overheat or cool down
Speaker 1: so much that it becomes solid again. And then the
Speaker 1: base of this container was essentially a drain, so there's
Speaker 1: like a hole at the bottom of the container that
Speaker 1: liquid chocolate could flow through. Attached to that was a tube,
Speaker 1: and inside the tube they put a series of metal
Speaker 1: mesh screens, and the screens were what generated the electric field.
Speaker 1: They had electricity running to those screens and creating electric
Speaker 1: field that way in the direction of the flow of chocolate,
Speaker 1: so the chocolate would end up flowing very smoothly through
Speaker 1: the tube and didn't have any issues. At the other end,
Speaker 1: they had another vessel container that the liquid chocolate would
Speaker 1: flow into, it would cool down solidify. So once that
Speaker 1: liquid chocolate flowed through into the collecting vessel, uh and
Speaker 1: once it was free of the electric field, the cacao
Speaker 1: particles they went back to their original shape immediately. Again.
Speaker 1: They didn't have to transform or anything. It wasn't a
Speaker 1: gradual process. They whoop moved back into those globe shapes
Speaker 1: that they typically are in, and the chocolate cooled and
Speaker 1: solidified and was, to all intents and purposes, indistinguishable from
Speaker 1: the chocolate that was being fed through at the top,
Speaker 1: you know, at that top chamber. So they were able
Speaker 1: to reduce the viscosity of the flowing chocolate uh and
Speaker 1: to the to the point where it was no there
Speaker 1: were no issues of clogging. It's perfectly fine. So they
Speaker 1: were able to prove that their hypothesis was correct, that
Speaker 1: in fact, this electric field applied in this way would
Speaker 1: decrease chocolates viscosity. Hooray. But there's more to it than that,
Speaker 1: So this experiment was not just a success. The researchers
Speaker 1: actually realized that it had a lot more implications than
Speaker 1: just having chocolate flow freely through a machine. Uh. That Again,
Speaker 1: the reason why chocolate has such a relatively high fat
Speaker 1: content is to create that oily fluid to reduce viscosity,
Speaker 1: to have the cacao particles suspended within it at a
Speaker 1: density that's low enough so you're not likely to clog
Speaker 1: up the machines. But if you use this approach, if
Speaker 1: you use the electric fields to reduce the viscosity, you
Speaker 1: don't need as much oil or fat in your chocolate content.
Speaker 1: You could actually start with a recipe that has less
Speaker 1: fat in it, and the electric fields would take care
Speaker 1: of the viscosity problem, so you don't have to have
Speaker 1: as much fat there. That also means you can have
Speaker 1: more cacao in your mixture. It could be a higher
Speaker 1: proportion of the overall recipe. So they found that they
Speaker 1: could reduce the fat content in certain types of chocolate
Speaker 1: by as much as twenty percent and still have no
Speaker 1: negative impact on the fluids viscosity. Now, it depends on
Speaker 1: what type of chocolate they were using. They were they
Speaker 1: were actually using name brand chocolates, you know, like like
Speaker 1: chocolate bars. They would try different types and depending on
Speaker 1: the type, they could actually end up removing up to
Speaker 1: the fat in the mixture and still have the chocolate
Speaker 1: flow without any problems. And beyond that, the researchers said
Speaker 1: that people who were tasting the chocolate afterward, because keep
Speaker 1: in mind, other than the fact that there was less
Speaker 1: fat in it, there was really no difference between the
Speaker 1: original chocolate and the end result, they said that the
Speaker 1: end result chocolate actually tasted better to them. He said,
Speaker 1: I had a more intense cacao flavor. It was more
Speaker 1: chocolate d e than the original chocolate. Now that could
Speaker 1: be just subjective, or it could be purely psychological, but
Speaker 1: it's not outside the realm of possibility that by increasing
Speaker 1: the the proportion of chocolate of cacao in your mixture
Speaker 1: because you've removed some of the fat, so you've got
Speaker 1: more cacao per unit of chocolate than you would previously,
Speaker 1: that you would also affect the taste. It is entirely
Speaker 1: possible that that is true. It hasn't really been tested
Speaker 1: on a scientific level. It's mostly people saying this tastes
Speaker 1: really good. Also, I should mention this is not the
Speaker 1: same as fat free chocolate. Fat free chocolate is essentially
Speaker 1: using some different type of fluid other than oil to
Speaker 1: suspend cocow particles. So fat free chocolate is has that
Speaker 1: particular weird taste. It's not It's not the same as
Speaker 1: the stuff that Typal University was producing. So, uh, I
Speaker 1: just want to clear that up. It's not like you
Speaker 1: would take take a bite of a brand new chocolate
Speaker 1: bar that was made using this procedure and they, oh,
Speaker 1: this tastes like fat free chocolate. No, So the end
Speaker 1: result here is that we could end up with better
Speaker 1: tasting chocolate with less fat in it in the future,
Speaker 1: which seems pretty awesome to me. Now, Earlier I mentioned
Speaker 1: that electro rheological fluids are also called smart fluids, that's
Speaker 1: cause these fluids can change their viscosti almost instantly in
Speaker 1: the presence of an electric or magnetic field and then
Speaker 1: go right back to what they were before once the
Speaker 1: field is turned off, and they become really important in
Speaker 1: ways beyond making superior chocolate. For example, car manufacturers have
Speaker 1: been using smart fluids and suspension and breaking systems. Uh.
Speaker 1: The fluid can actually go from relatively thin too thick
Speaker 1: and just a moment's notice, which makes it superior to
Speaker 1: a lot of mechanical solutions that would take time to
Speaker 1: propagate through a system. And you can have a variable
Speaker 1: suspension in this way. Imagine that you have a suspension,
Speaker 1: it's a fluid suspension, like literally it's a suspension for
Speaker 1: a car with fluid in it, not that it was
Speaker 1: a fluid that has a suspension in it. It's kind
Speaker 1: of confusing. So car suspension's got fluid in it. Very
Speaker 1: high end sports cars have these, and you can set
Speaker 1: your suspension to different modes, like you can predetermine which
Speaker 1: mode you want at any given time. So let's say
Speaker 1: you're gonna be driving on like a racetrack, a nice
Speaker 1: smooth racetrack, and you're really gonna push the car to
Speaker 1: its limits. You might want a pretty stiff suspension for
Speaker 1: that to really be able to feel the car as
Speaker 1: you're driving along this very smooth surface. But that stiff
Speaker 1: suspension would be torture device. If you were driving down
Speaker 1: a normal everyday road that had some bumps and maybe
Speaker 1: some potholes in it, that would be very jarring. You
Speaker 1: would feel every single little bump. So in that case
Speaker 1: you'd want a more you know, loose suspension, a little
Speaker 1: spring in it. So you might want to reduce the
Speaker 1: viscosity of the fluid inside the suspension to allow for
Speaker 1: more um give really, and you could do that with
Speaker 1: a smart fluid and just change the electric or magnetic
Speaker 1: field that ends up affecting the viscosity of the fluid.
Speaker 1: So you can actually have settings and say I want
Speaker 1: a very stiff suspension in this circumstance, and so it
Speaker 1: generates electric field, the viscosty increases and you get your
Speaker 1: stiff suspension. Or he might say, oh, I want it
Speaker 1: to be a more forgiving suspension, and it turns off
Speaker 1: that electric field, the viscosity decreases and you have your
Speaker 1: more your your suspension when more given it, it's a
Speaker 1: pretty cool idea. At chatted with Scott Benjamin about this
Speaker 1: before I came in here. He was very interested when
Speaker 1: I started talking about chocolate, but then when I started
Speaker 1: talking about smart fluids, he really lit up because he
Speaker 1: knew exactly what I was talking about. I mean, Scott
Speaker 1: is a car genius and knows everything there is to
Speaker 1: know about cars, it seems. So we had a good
Speaker 1: discussion about, you know, the physical properties of smart fluids
Speaker 1: and why they behave the way they do. So this
Speaker 1: technology could be used in lots of different applications moving forward.
Speaker 1: When you can induce some mechanical change in a fluid
Speaker 1: with something as simple as an electric or magnetic field,
Speaker 1: a lot of different opportunities open up. But for me,
Speaker 1: you know, I'm happy with the chocolate thing. I'm going
Speaker 1: to settle for that because I do love me some chocolate.
Speaker 1: Al Right, guys, Well, this kind of wraps up this
Speaker 1: episode where I really wanted to look at the physics
Speaker 1: and technology behind ostensibly making chocolate manufacturing more uh smooth
Speaker 1: and efficient, but ultimately could result in better, more delicious,
Speaker 1: less fattening chocolate. That doesn't necessarily mean we should all
Speaker 1: go out and eat more chocolate by the way, not
Speaker 1: that that ever stops me, but I feel like as
Speaker 1: an adult, I have to at least say, don't go
Speaker 1: out and just eat more chocolate. Even if we ultimately
Speaker 1: have chocolate with less fat in it, that's not that's
Speaker 1: not a good excuse. Uh, do as I say, not
Speaker 1: as I do. Anyway, I wanted to invite you guys
Speaker 1: to get in touch with me. Let me know what
Speaker 1: sort of topics you would like me to cover in
Speaker 1: the future. I've got some interesting future topics lined up.
Speaker 1: He would like a quick peek into the future. Pretty soon,
Speaker 1: I'm going to be doing an episode about the story
Speaker 1: of Pixar. I'm gonna do a full maybe two parter
Speaker 1: on that because it's a it's a good long story.
Speaker 1: I've got a an interview lined up with some folks
Speaker 1: to talk about Amazon Alexa and developing apps for that
Speaker 1: and what Alexa might mean in the future. I've got
Speaker 1: uh an episode lined up with Mr Scott Benjamin, whom
Speaker 1: I just mentioned about robo rites, and also the tragic
Speaker 1: tale of the first Death and an autonomously operated vehicle.
Speaker 1: So we've got a lot of different stories coming up.
Speaker 1: But if you guys have a specific text story, or
Speaker 1: technology in general that you would like me to cover.
Speaker 1: Get in touch with me, Let me know I'm I
Speaker 1: love hearing from you guys. You can email me. The
Speaker 1: address is text stuff at how stuff works dot com,
Speaker 1: or you can drop me a line on Facebook or
Speaker 1: Twitter at both. I am Text Stuffs H. S W.
Speaker 1: And I'll talk to you again really soon. For more
Speaker 1: on this and thousands of other topics, is it how
Speaker 1: stuff works dot com, wh