字幕列表 影片播放 列印英文字幕 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 that “natural” is 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 are “indirect” ways of removing caffeine, the solvents never touch the beans! A more direct way uses CO2. After the beans are soaked in water, they’re 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 pointless… some 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.
B2 中高級 美國腔 咖啡是如何去咖啡因的 (How Coffee is Decaffeinated) 266 30 Cindy Peach Wang 發佈於 2021 年 01 月 14 日 更多分享 分享 收藏 回報 影片單字