Pratique du Shadowing: How to unboil an egg - Eleanor Nelsen - Apprendre l'anglais à l'oral avec YouTube

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It's so obvious that it's practically proverbial.
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30 phrases
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It's so obvious that it's practically proverbial.
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You can't unboil an egg.
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Well, it turns out you can, sort of.
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What thermal energy does to the eggs' molecules, mechanical energy can undo.
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Eggs are mostly made of water and proteins.
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The proteins start off folded up into intricate shapes, held together by weak chemical bonds.
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Adding heat disrupts those bonds, allowing the proteins to unfold, uncoil, unwind and wiggle freely.
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This process is called denaturing.
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The newly liberated proteins bump up against their neighbors and start to form new bonds with each other, more and more as the heat increases, until finally, they're so entangled that they gel into a solid mass, a boiled egg.
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That entanglement might look permanent, but it's not.
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According to a chemical idea called the principle of microscopic reversibility, anything that happens, like egg proteins seizing up, can theoretically unhappen if you retrace your steps.
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But adding more heat will tangle the proteins further, and cooling them down will only freeze them, so here's the trick: spin them around ridiculously fast.
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I'm not kidding.
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Here's how it works.
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First, scientists dissolve boiled egg whites in water with a chemical called urea, a small molecule that acts as a lubricant, coating the proteins' long strands and making it easier for them to glide past each other.
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Then, they spin that solution in a glass tube at a breakneck 5000 rotations per minute, making the solution spread out into a thin film.
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Here's the key part.
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The solution nearest the wall spins faster than the solution closer to the middle.
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That difference in velocity creates sheer stresses that repeatedly stretch and contract the proteins until eventually they snap back into their native shapes and stay there.
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By the time the centrifuge stops spinning, the egg white is back in its original unboiled state.
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This technique works with all sorts of proteins.
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Bigger, messier proteins can be more resistant to being pulled apart, so scientists attach a plastic bead to one end that adds extra stress and encourages it to fold up first.
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This unboiling method won't work with a whole egg in its shell since the solution has to spread throughout a cylindrical chamber.
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But the applications go way beyond uncooking your breakfast, anyhow.
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Many pharmaceuticals consist of proteins that are extremely expensive to produce, partly because they get stuck in tangled up aggregates, just like cooked egg whites and have to be untangled and refolded before they can do their jobs.
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This spinning technique has the potential to be an easier, cheaper and quicker method than other ways to refold proteins, so it may allow new drugs to be made available to more people faster.
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And there's one more thing you need to keep in mind before trying to uncook all of your food.
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Boiling an egg is actually an unusual cooking process because even though it changes the way proteins are shaped and bound together, it doesn't actually change their chemical identity.
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Most types of cooking are more like the famous Maillard reaction, which makes chemical changes that turn sugars and proteins into delicious caramel crunchiness and are a lot harder to undo.
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So you might be able to unboil your egg, but I'm sorry to say you can't unfry it...yet.
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About This Lesson

In this lesson, you will practice English speaking skills by exploring a fascinating scientific concept presented in the video "How to unboil an egg" by Eleanor Nelsen. Through listening and repeating complex vocabulary and expressions, you will improve your English pronunciation and comprehension. Additionally, this lesson will challenge you to engage with scientific language, which is often less familiar but essential for a variety of academic and professional contexts. As you dive into the explanation of protein structures and cooking processes, you’ll simultaneously enhance your overall fluency in English.

Key Vocabulary & Phrases

  • Denaturing - The process by which proteins lose their natural structure due to external factors like heat.
  • Microscopic reversibility - A chemical principle suggesting that actions can theoretically be undone.
  • Centrifuge - A machine that spins substances at high speeds to separate components.
  • Shear stress - A force that causes layers of material to slide past each other.
  • Pharmaceuticals - Medicinal drugs produced for various health treatments.
  • Urea - A chemical compound used in the process of unboiling proteins.
  • Maillard reaction - A chemical reaction that causes browning and flavor changes during cooking.

Practice Tips

For effective shadow speech practice, focus on mimicking the pacing and intonation of Eleanor Nelsen as you listen to the video. Given her clear articulation and approachable tone, you can follow these steps:

  • Listen and Repeat: Play sections of the video multiple times, pausing after phrases to repeat them aloud. This will help you improve your English pronunciation and fluency.
  • Pace Yourself: The speaker maintains an informative yet relaxed speed. Aim to match this pace to keep your practice natural and effective.
  • Record Yourself: Use a recording device to capture your attempts. Compare your speech to the original and identify areas for improvement regarding clarity and fluency.
  • Focus on Vocabulary: Make sure to practice each new vocabulary term in complete sentences. This will expand your vocabulary while providing context for each term.
  • Engage with Content: After shadowing, try to summarize what you've learned in your own words. This practice enhances comprehension and prepares you for IELTS speaking practice where articulation of ideas is crucial.

By integrating these english speaking practice techniques, you'll not only grasp the scientific content presented but also sharpen your overall communication skills, making your English more fluent and expressive.

Qu'est-ce que la technique du Shadowing ?

Le Shadowing est une technique d'apprentissage des langues fondée sur la science, développée à l'origine pour la formation des interprètes professionnels. Le principe est simple mais puissant : vous écoutez de l'anglais natif et le répétez immédiatement à voix haute — comme une ombre suivant le locuteur avec un décalage de 1 à 2 secondes. Les recherches montrent une amélioration significative de la précision de la prononciation, de l'intonation, du rythme, des liaisons, de la compréhension orale et de la fluidité.

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