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  • We need to talk about meat.

  • Unless youre a practicing vegan or vegetarian, youre probably getting a large percentage

  • of your protein from livestock like cows, pigs, and chickens.

  • Now I’m not here to judge your eating habits.

  • I’m addicted to the taste of flesh myself,

  • but our meat-heavy diets are bad for the planet.

  • Livestock raised for food makes up about 14-18% of our greenhouse gas emissions, and the land

  • requirements to grow their food is responsible for about 80% of all deforestation in the

  • Amazon.

  • But there may be a way to have our beef-cake and eat it too, as researchers from Harvard

  • just announced theyve developed a technique that brings realistic lab-grown meat one step

  • closer to the dinner table.

  • The issue the team was trying to solve was how to grow skeletal muscle tissue in long

  • thin fibers, like how it occurs naturally in livestock.

  • If youve ever looked at the grain of a steak or at shredded pork or chicken, youve

  • seen what I’m talking about.

  • Mimicking that fiber structure has been a huge challenge for lab-grown meat.

  • You can’t grow muscle cells like that in a petri dish all by themselves.

  • They need something to hold on to as they grow.

  • So the researchers set out to find a material they could use to grow their cells in 3D.

  • The material had to be edible, something the cells could easily latch on to, and cheap

  • enough to produce to keep costs down.

  • The scientists settled on gelatin, and they spun it into fibers using a technique inspired

  • by cotton-candy.

  • The finished product is similar to the supportive extracellular matrix of natural muscle tissues.

  • With their gelatin nanofibers spun, the researchers tried growing rabbit and cow muscle cells

  • on them.

  • While the finished products did not contain as many muscle fibers as natural meat, they

  • did achieve a texture that was similar to the real thing.

  • Now don’t go thinking lab-made beef is what’s for dinner.

  • There are a number of other hurdles scientists need to clear before more sustainable and

  • slaughter-free meat is on store shelves.

  • For example, scientists will have to figure out how to grow cells without using animal

  • serum, the most common being Fetal Bovine Serum, or FBS.

  • FBS is harvested from the fetuses of slaughtered pregnant cows.

  • It’s very expensive, and most lab-grown meat techniques rely on large quantities of

  • it.

  • So any product that relies on FBS isn’t helping much to cut down on greenhouse gasses,

  • cost, or cruelty.

  • There’s also the matter of taste.

  • Meat is more than muscle; its flavor and juiciness also comes from fat.

  • Growing fat cells in a lab that mesh with muscle and recreate the texture of steak has

  • proven to be a challenge.

  • And to get cells to reach maturity, we're searching for better sources of stem cells.

  • But even if these technical hurdles are all solved, the finished product may be only slightly

  • less damaging to the environment than raising livestock.

  • Because of the energy lab-grown meat takes to manufacture, growing all our steaks and

  • burgers in a dish may cut greenhouse gas emissions from beef by as little 7%, and actually produce

  • about 4-5 times more greenhouse gasses than chicken or pork.

  • So, lab-made meat is still a work in progress.

  • And even if it’s eventually appetizing, cheap, and eco-friendly, it may still face

  • challenges from the powerful livestock industries that have a beef with competition.

  • Theyre already pushing lawmakers to pass laws that forbid calling itmeat,” or

  • they may come up with some other marketing campaign to turn public opinion against it.

  • Then again, they may see the potential upsides of lab-grown meat, like some large meat processing

  • companies have, and invest in projects developing alternative proteins.

  • But even with money pouring into research and progress being made by scientists like

  • the ones at Harvard, lab-made meat that’s tasty, slaughter-free and environmentally

  • friendly is still a long ways away.

  • Say they perfect lab-made meat and create a burger patty that was indistinguishable

  • from ground beef.

  • Would you eat it?

  • Why or why not?

  • Let us know in the comments.

  • Make sure to subscribe to Seeker and thanks for watching.

We need to talk about meat.

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B2 中高級

實驗室培養的肉類的這一突破可以讓它看起來像真正的肉一樣。 (This Breakthrough in Lab-Grown Meat Could Make it Look Like Real Flesh)

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    林宜悉 發佈於 2021 年 01 月 14 日
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