IRA Flatow: It’s Science Friday. I will go flatow. I love pasta. I love to cook it. I love to make pasta dishes. There are really two reflection schools on what to do with spaghetti. There are those who slide whole craghetti whole whole in boiling water. And then there are people like me who try to divide the spaghetti into two pieces so that it fits more easily in the pan.
But you know what’s going on – you find that it is still divided into three pieces and never offers two. And it’s not just me. For decades, this humble food has prompted physicists around the world to try to understand the mysterious properties of pasta. Why can’t you divide it into two pieces? And what is in the secret sauce that makes the cacio e pepe so difficult to perfect?
Well, my next guest wrote on scientists who prepare the answers to these questions and more. He did it for a recent room for the BBC. Joseph Howlett is editor in mathematics at Quanta magazine, based in New York. Joseph, welcome to Science Friday.
Joseph Howlett: Thank you very much for inviting me, will go. I am a big fan.
IRA Flatow: I want to start with the addition of the famous physicist Richard Feynman at the Spaghetti Science Club. Not that I am surprised, given the whimsical nature of his work, but how did he hug to study this kind of thing?
Joseph Howlett: Apparently it was one of his favorite foods. He noticed that if you hold the two ends of a bit of dry spaghetti and break it, you can never break it cleanly into two pieces. And he wondered why. I guess Feynman just can’t deactivate his physics brain. And he and his colleagues spent mainly overnight breaking pieces of spaghetti until the kitchen floor is covered with. It is a piece of physical folklore now, that Feynman had this obsession for spaghetti.
IRA Flatow: WOW. So it was only the beginning of his romance with spaghetti, right?
Joseph Howlett: Yes, I mean, the question he opened has become a real search line that has not ended, even now. And people always discover the mysteries of spaghetti rupture.
Ira Flatow: So how have other physicists built this curiosity – on its curiosity?
Joseph Howlett: Well, for a long time, no one could really understand what was going on until 2005, when some researchers made a model that explained how it fragments and how the tension you build in a bit of spaghetti is distributed on spaghetti so that it must break more than one place at a time.
And this won an IG Nobel Prize the following year, 2006. It was therefore a kind of ostensible answer to the question. But scientists continued to study it. And just a few years ago, a group of MIT mathematicians understood that you could divide it into two pieces if you turn it first. I know it is difficult to imagine twisting a fragile spaghetti. But with laboratory equipment, you can do it. You can twist so well that there is no tension in the middle. So, it is sort of distributed through everything. And then if you break it, it will break perfectly in two pieces.
IRA Flatow: The geek in me must try this.
Joseph Howlett: You will finish at night like Feynman, I’m sure, with the kitchen floor covered with spaghetti.
IRA Flatow: I should be another Feynman. You write on another pressing problem, the problem of spaghetti. When you suck spaghetti in your mouth, it always slaps you on your face, right?
Joseph Howlett: Yeah. You always end up with sauce on your face – or at least I did it when I blurred simple strands of spaghetti when I was a child. And a physicist and mathematician, George F. Carrier, was really intrigued by this problem and wrote a serious academic treaty on this subject. He called it the problem of spaghetti. So he wondered essentially, when you interrupt him, why does he always take the side of your face? Why can’t you fear it in properly? And he was able to answer this with basic physics. It had to do with all these different acoustic modes that come into play when you move something long and folding.
IRA Flatow: Let’s go to the determination of the secret sauce. This pushed the Italian physicist to try to understand the physics of the reason why sometimes the Cacio e Pepe does not meet properly.
Joseph Howlett: Yes, so there was this group of Italian scientists at the Max Planck Institute in Dresden. And they deplore how they often tried to make cacio e pepe and noticed that the sauce, which is made of pasta and cheese water and nothing else, would sometimes form these large tufts that you could never break. And you should throw your whole batch of pasta.
And it was horrible for them, and it was particularly embarrassing when they invited their German friends and spoiled in front of them. They therefore decided to prepare a device to study why it happens and if there is a way to get around this.
Ira Flatow: And what have they discovered?
Joseph Howlett: Fortunately for us, these Italian scientists are advanced experts on the physics of the separation of phases, that is to say when you have a solution which is a mixture of different things, and they form liquid droplets in the solution. It was the key so that they understand what was going on when things were expanded in what they called the mozzarella phase. For them, it was the separation of phases that made a tuft of cheese in the pasta that you could not break.
They understood that it had to do with a few things. And what they have achieved is that pasta water has starch, which is essential to mix the sauce, but not enough to make sure that the approval does not occur. So if you accidentally heat your pasta enough – and that could make a difference of a few degrees – they found that these clusters are inevitably formed. And the way to surround it, they decided, was artificially adding the additional starch – more than pasta water could not provide. So they did that with corn starch. And if you add this extra little starch, you can completely avoid the possibility of the mozzarella phase, regardless of the amount of sauce.
IRA Flatow: WOW. It is such a popular dish, you would have thought that a famous chief would have understood it instead of certain scientists.
Joseph Howlett: This is exactly what they understood. As they wrote the newspaper, they found a YouTube video of a famous Roman chef, a Michelin star chief Luciano Monosilio, who had said exactly in his video. He said – he made a recipe for Cacio E Pepe where you add an additional cornstarch and you can completely avoid this agglomeration phenomenon. It is a kind of infallible recipe. The researcher says that this is the only time they cited a recipe in a scientific article.
Ira Flatow: Very well, well, so they must understand that there must be something that helps us to better understand science or life on earth when we understand the perfect recipe for the cacio e pepe.
Joseph Howlett: Yes, it turns out that what is happening when you spoil your Cacio E Pepe could be the same kind of accident that has started life on earth.
IRA Flatow: Really?
Joseph Howlett: Yes, because this phase separation thing, forming tufts in a liquid, you can somehow imagine that in primordial goop, where things were precursors of cells are initially formed. You have this dispersed solution. And then you need important things, proteins, to find a way to bring together and build more complex molecules. And people think it can happen due to the physics of phases separation.
Ira Flatow: We have just talked about a few different studies, which raises the question, why are physicists so obsessed with spaghetti? I mean, it’s just flour and water, right?
Joseph Howlett: Exactly. And I think it’s part of the story. I mean, I asked all the scientists to whom I spoke – what are the spaghetti make you all obsessed with? One thing that came a lot was exactly what you said, that it is a very simple substance. It’s just flour and water. And yet, you draw all these complicated mechanical properties. He is brittle and steep and strong, and he breaks in these strange ways. And yet, when you cook it, it becomes this elastic thing, soft and flexible that you can attach to the knots. It’s slippery, and it’s also a bit sticky. It’s so much with only two ingredients.
IRA Flatow: And it’s cheap to experience.
Joseph Howlett: Yes, it was also a large part of this. Scientists who broke spaghetti in two, they said, yes, we could have done with brittle plastic rods. But they are very expensive. You cannot break them and fill the floor of your kitchen with them at the same price as you can for a spaghetti box.
IRA Flatow: Are there any advice that you can give us on cooking or pasta preparation, knowing science, how could it help us?
Joseph Howlett: This story encourages me to try to have the same kind of curious spirit as Feynman and others, to seek science in the banal and perhaps never to deactivate this part of your brain which requires, why is it like that?
IRA Flatow: Yes, he was very good at doing that. And you are very good at explaining it. I want to thank you for taking the time to be with us today.
Joseph Howlett: Thank you very much, go.
IRA Flatow: Joseph Howlett, editor in mathematics at Quanta magazine, based in New York.
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