字幕列表 影片播放 列印英文字幕 [♪INTRO] If somebody gives you the choice between two tasty-looking snack cakes -- but one is labeled 'naturally flavored', and the other 'artificially flavored' -- most people would probably go with the natural one. It sounds better. Who wants to eat food that's fake? I like real food. But those labels can be pretty misleading. In fact, the flavorings could be chemically identical. There are rules to what gets labeled “natural” or “artificial,” but they're pretty subtle. And you definitely don't need to avoid artificial flavors to stay healthy or be eco-friendly. The only reason you might want to opt for the natural version in some cases is its … just, its flavor? In the US, artificial and natural flavors are defined by the Food and Drug Administration, because that's the agency that gets a say in how companies market and label their foods. So first, the term “flavors” itself refers to ingredients that are in the food mainly for their taste, rather than any nutritional value. So an apple in an apple pie would certainly be adding to the overall flavor, but it would not technically be considered a flavor or flavoring. And the FDA considers something a 'natural' flavor if it comes from a plant or animal. That source could be virtually anything: fruit, bark, herbs, veggies, meats. The list is long. But if it's made from a plant or animal, it's natural. If not, it's artificial. It does get a little more complicated than that, but in the vast majority of cases, the difference between the two is only the source. We're sticking to specifics of the US here, but plenty of other countries differentiate these flavors along the same lines, so you'll see similar claims on their food packaging. Seems simple enough, but if you think about how we experience flavor, you can see why this whole binary system the FDA has cooked up is not necessarily all that useful. Because what makes your favorite chocolate chip cookies so delicious comes down to the molecules you taste and smell, not where those molecules come from. They're chemicals, whether they come from natural sources or are made from scratch in a lab. And in many cases, the molecules in natural and artificial flavors are exactly the same — down to the placement of each atom and bond. That's because for a lot of common flavors, we know the main chemical behind them, and whether you purify it from fruit or make it synthetically, a compound is a compound is a compound. Take the vanilla you might use when you bake cookies. The main flavor component of vanilla -- and the one we recognize as having that sweet, characteristic taste -- is a chemical called vanillin. You can naturally extract it from vanilla beans by soaking them in water and alcohol. Or, you can make the exact same chemical in the lab. If you go the all-natural route, expect to pay big bucks, though, because vanilla beans are the fruits of finicky tropical orchids. They're a huge pain to grow and harvest. And vanilla is the world's most popular flavor, we cannot grow enough beans to flavor everything we want using only the real stuff. There is another natural way to get vanilla flavor, with something called castoreum, but that's not likely to be a fan favorite. That's because it comes from the castor sacs of beavers, which are located down near their tails. Basically, flavoring via beaver butt. Milking beavers for their secretions is not exactly a high-volume industry either, so castoreum is too expensive to put in most foods. But in the lab, you can make the same vanillin in huge batches and for much less money by doing some fancy chemistry on paper pulp or petroleum derivatives. That may sound less appetizing than getting it from the beans, but remember: the molecule you get at the end is exactly the same. And, it's how we're able to vanilla-fy most of the foods we eat. So maybe don't write off artificial vanilla just because it's not natural. You'll save some big bucks. Then there are also some misconceptions about the environmental impact. Counterintuitive as it might sound, natural flavorings aren't always so great for nature. They can have much bigger environmental footprints than their artificial counterparts. Take massoia lactone, a chemical that tastes like coconut, which you can find in the bark of certain trees in Southeast Asia. The tricky part is if you strip off the bark to get it, you kill the tree. So, as much as we might want to have that lovely pina colada flavor, the natural version is really inefficient and unsustainable. Whereas synthetic chemists can whip up massoia lactone in the lab, no tree stripping necessary. Granted, artificial flavorings aren't perfect for the planet either. They're often made from oil, and can require special materials that aren't environmentally-friendly. Production can also create wastewater. Still, that's usually better than killing entire groves of trees or going through thousands of kilos of fruit in search of specific flavor compounds. There is one major downside to keeping things strictly in the lab, though: the taste. Because while synthetic vanillin is the same molecule you'll find in the stuff from vanilla beans, real vanilla has hundreds of other compounds that subtly change the flavor. Artificial vanilla is a pretty good substitute because around 80% of vanilla flavor comes from that one vanillin compound. Most people can't tell the difference. But other flavors are much harder to replicate. Artificial strawberry might be delicious, for example, but if you think about it, it doesn't really taste like strawberries. That's because you simply can't reproduce that flavor very well with one or two chemicals. It's super complex. So, the purity you get with artificial methods may sometimes make for less-sophisticated flavors. On the other hand, it also means that those flavors are better-known to scientists, and more rigorously tested. If this runs counter to your intuition, you're not alone. Packages proudly proclaiming 'no artificial flavors' are trying to appeal to the common feeling that substances from Mother Nature are inherently safer and better than ones invented and produced by people. That's called the naturalistic fallacy. But nature isn't infallible, and there's all kinds of stuff out there that's natural, but will also super kill you. Just because a flavoring comes from a plant or animal doesn't mean it's safer or healthier. Which is why US flavor regulations apply to both natural and artificial flavors. It's a system called Generally Recognized As Safe, or GRAS. Basically, back in the mid-20th century, the FDA decided that food additives should be tested, although they could be exempted from review if experts already agreed that the substance was safe. Since the rules took full effect in the late 1950s, just two flavors have been banned, one natural and one artificial: calamus, which comes from a plant also known as sweet root; and cinnamyl anthranilate, a synthetic compound that gives a grape or cherry flavor. Some flavorings have raised other types of health flags, like diacetyl, the artificial buttery flavoring in microwave popcorn. If it's inhaled in extremely large amounts — like if you work in a popcorn factory and don't use protective equipment — it can cause a lung disease known as popcorn lung. But eating it isn't a problem, so we still use it. In theory, it's still possible that some flavors we use have minor negative health effects we just don't know about, even with this testing system. One complication is that the evidence is summarized by an industry group. But since the rules apply to both types of flavors, there's no reason to be extra suspicious of the artificial ones. Another part of artificial flavoring's bad reputation comes from the fact that it's in processed foods, which are less healthy for you — they're often high in sugar and fat while also being low in fiber and nutrients. But that's not the flavoring's fault. And of course, natural flavoring is used for the exact same thing. Perhaps the most misleading example of this is orange juice. Americans used to get most of their orange juice from concentrate, but these days, we tend to buy it in cartons where the juice doesn't need to be diluted. It seems like a fresher option, and companies have marketed it that way to get a premium price. But the juice isn't as fresh as they make it sound. Because of the realities of large-scale production, the juice ends up sitting in tanks for months at a time. To keep it from spoiling, producers pasteurize it and also remove all the oxygen in a process called deaeration. To be fair, that processing is important to keep the juice safe to drink. But it also removes a bunch of the nicer flavor compounds that make freshly squeezed juice so refreshing. The juice might not be from concentrate, but companies still re-flavor it right before it's put in the carton, with what people in the industry call juice packs. The packs are a mix of flavors, usually from oranges, orange oil, or orange essence. So technically, they have natural sources. But that doesn't mean the flavor is coming from freshly-squeezed orange juice, or that the juice is somehow less processed and healthier because the flavorings are natural. Once you find out what the terms “natural” and “artificial” really mean, you start to see this type of misleading marketing everywhere. But if you think it's confusing now, just wait a few years. Because biotech is getting in on flavorings, blurring the lines even more. Companies are trying to come up with new ways to make flavors that still count as 'natural' under current labeling regulations -- even though the source may be bacteria or yeast, rather than any recognizable plant or animal. With genetic engineering, you can program microbes to produce certain flavor molecules, then isolate the molecules and use them just like other flavorings. That could be a more efficient and eco-friendly solution in some cases, especially for hard-to-source flavor compounds. But in a way, it would make the labeling claims on food packaging even more meaningless. Like, is that all-natural vanilla flavor from vanilla beans or a very special strain of yeast? If you wanted the natural stuff for the more nuanced flavor, you'd have no way of knowing what you were getting. For now, just don't be fooled by claims that sticking to natural flavors is healthier or better for the environment. Tastes and flavors are based on chemistry, and a lot of the time, the artificial ones are just as good. Thanks for watching this episode of SciShow! If you're interested in learning more about flavor chemistry, you can check out one of our previous episodes, about 5 chemicals that are in everything you eat. [♪OUTRO]
B1 中級 美國腔 天然和人造风味的真正含义是什么?(What Do 'Natural' and 'Artificial' Flavors Really Mean?) 12 1 joey joey 發佈於 2021 年 05 月 06 日 更多分享 分享 收藏 回報 影片單字