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  • The best part of waking up is no caffeine in your cup. Wait.. what? that’s no fun.

  • Hey everyone Julia here for DNews

  • I need my caffeine in the morning. i’m a total zombie without it. And so are millions

  • of other Americans. Nearly 83% of the population drinks coffee, according to the National Coffee

  • Association.

  • Another survey by Zagat found that most people drink 2.1 cups a day. And that’s not a bad

  • thing. Some studies show that coffee can boost your focus and even help prevent diabetes

  • and lower the risk of liver disease. But for some the caffeine leaves them anxious and

  • jittery.

  • But maybe those people still like the taste but not the perks, so for them, decaf is the

  • way to go. But how do you decaffeinate coffee? Big shout out to our viewer Jasper Lithgow

  • for asking this very good question.

  • Caffeine occurs naturally in some plants, like the cocoa tree, Coffea plants, and Camellia

  • sinensis from which tea is made. Like I said, naturally, so any decaffeinating process is

  • pretty unnatural.

  • The first decaffeination process was really unnatural. it was even a little dangerous.

  • German merchant Ludwig Roselius accidently discovered that salt water soaked the caffeine

  • out of his coffee beans while they shipped across the ocean. And for some reason he thought

  • this was a totally good idea.

  • So he tried to recreate it by steaming the beans and using a solvent to remove the caffeine.

  • Unfortunately he picked benzene which according to the Center for Disease Control is a known

  • carcinogen and can cause some serious discomfort like, stomach pain, dizziness and even death.

  • So yeah that’s not good.

  • While benzene is no longer used, other chemicals are still used to remove caffeine. The process

  • is a little complicated. Beans are first soaked in water, which opens the pores in the bean

  • so the caffeine dissolves. But so does some of the flavor. This water then gets treated

  • with a solvent, typically dichloromethane and ethyl acetate, for about ten hours. This

  • separates the caffeine from the flavors. Finally the mix gets heated to evaporate the solvents

  • and the caffeine. This treated water gets returned to the bean so they can re-soak up

  • the flavor.

  • Typically this is what thatnaturalis talking about when a package says it’s

  • naturally decaffeinated”. I know, i know, it doesn’t sound completely naturally. But

  • one of the solvents, ethyl acetate pretty natural, it’s found in a lot of fruits.

  • Unfortunately it’s difficult to extract, so most manufacturers use a synthetic version.

  • Another process gets a little fancier. The Swiss Water Process relies on simple concepts

  • like osmosis and solubility to remove the caffeine. Using water from mountains in british

  • columbia, the beans are bathed in really hot water to draw out the caffeine. which is then

  • drawn through a charcoal filter which catches the large caffeine molecules but not the other

  • good things you’d want to stay in the bean like the flavor. So then that water is then

  • returned to the beans to put the flavor back.

  • But these areindirectways of removing caffeine, the solvents never touch the beans!

  • A more direct way uses CO2. After the beans are soaked in water, theyre placed in a

  • stainless steel container called an extraction vessel. Liquid CO2 is then forced into the

  • beans at enormous pressure. At 1,000 pounds per square inch! The CO2 draws out the caffeine

  • but leaves flavors behind.

  • That’s so weird and science fiction-y. While decaf might seem weird, and kind of

  • pointlesssome studies show it still retains some of the health benefits!

  • I mean decaf still has caffeine. One study published in the Journal of Analytical Toxicology

  • found that most major brands have around 8.6 milligrams to 13.9 milligrams of caffeine.

  • Compared to a normal cup which has around 85 milligrams.

  • One study published in the journal Nutritional Neuroscience found that a cup of decaf might

  • help the way the brain metabolizes energy. It could also prove useful for helping prevent

  • and treat decline from diabetes or aging.

  • No matter your coffee style, there’s no doubt caffeine can pack a punch. Trace explains

  • exactly what caffeine does you in this video here.

  • How much coffee do you drink? Would you do decaf? Let us know in the comments below.

  • Or if you have any other questions about the science of food, leave those too! We could

  • answer them in a future episode.

The best part of waking up is no caffeine in your cup. Wait.. what? that’s no fun.

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咖啡是如何去咖啡因的 (How Coffee is Decaffeinated)

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    Cindy Peach Wang 發佈於 2021 年 01 月 14 日
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