海绵宝宝大电影出水:味道的科学

译者 zjgjasoncool

Whether we’re talking about America’s obesity epidemic, mocking the “foodie” movement on “The Simpsons,” the USDA’s revamped food pyramid, or what they’re cooking up on “Top Chef,” food and eating are a national obsession — especially at this time of year.

无论我们是否正在谈论美国人肥胖，还是正在嘲笑“辛普森一家”中的美食家运动、美国农业部更新的食物金字塔或“高厨”真人秀中参赛选手做的菜，膳食的确是令全美国人关心的话题，尤其是在现在这个时候。

But just as fascinating is the hard science behind our intimate relationship with food. Gordon M. Shepherd, professor of neurobiology at the Yale School of Medicine, has spent a lifetime researching the brain mechanisms involved in olfaction (our sense of smell) and its impact on flavor perception in the brain. His new book is “Neurogastronomy: How the Brain Creates Flavor and Why It Matters,” out this month from Columbia University Press. Shepherd’s work is anchored in a burgeoning field within neuroscience — figuring out the mysteries behind our olfactory system, the ways in which smells are represented and processed in the brain.

但我们与食物紧密关系背后的科学事实同样令人着迷。耶鲁大学医学院的神经生物学教授Gordon M. SHepherd毕生都在研究嗅觉相关的大脑机制及其对大脑中味道感知的影响。他的新书《神经美食法—大脑如何产生味道及其重要性》本月已由哥伦比亚大学出版社出版。Shepherd致力于神经科学领域中一个快速发展的领域，即找出人的嗅觉系统背后的奥妙，气味在大脑中如何反映、如何处理。

Shepherd argues for the quintessential importance of olfaction in our everyday experience of food. Without smell, Shepherd says, there is no flavor. “Neurogastronomy” takes a detailed look at just how smelling in the nose, mouth and brain produces the unique experience of flavor that we associate with eating our favorite or least-favorite foods.

Shepherd论述了嗅觉在日常膳食中的典型重要作用。他还说，没有气味就没有味道。《神经美食法—大脑如何产生味道及其重要性》详细解释了气味如何在鼻腔、口腔和大脑中产生特定的味道，这些味道和我们最喜欢吃什么，最讨厌吃什么密切相关。

Shepherd explained why sitting down to Thanksgiving dinner triggers our instincts to overeat, how to do the nose-pinch test, and the best way to fool an experienced wine taster.

Shepherd还解释了为什么感恩节晚餐会激发我们暴食的本能，怎样做捏鼻子试验，和欺骗经验丰富的品酒师的最好办法。

What came first, your interest in gastronomy or your interest in neuroscience? Did one lead to the other?

问：“您对美食学的兴趣大一些？还是对神经科学的兴趣大一些？对其中一项的兴趣会导致对另一项也产生兴趣呢？”

My first interest is in neuroscience, in particular in the part of the brain that processes the sense of smell. And we all think we know what smell is … It’s when we sniff something in and it has a nice smell. But as I went further along I began to realize that increasingly smell was for sensing the flavor of food. It goes almost unrecognized as we eat our food because we think it all comes from taste in our mouths. The more research that I did on flavor, the more I realized that the sense of smell was the dominant sense in flavor — and that we are almost totally unaware of it. The science of smell is increasingly important for understanding flavor, and flavor really contributes to whether we are eating healthy or unhealthy diets.

答：“我的第一兴趣是神经科学，特别是大脑处理嗅觉的那一部分。我们所有人都认为自己知道嗅觉是什么。呼吸时嗅进一些东西，这种东西气味不错。但当我做进一步研究时我才越发认识到气味是用来感知食物的味道。人类一直在进食，可从没有认识到这一点，因为我们认为食物的味道来自于口腔中的味觉。随着我做过的关于味道的试验越来越多，我越发认识到对气味的感知决定了对味道的感知，可我们对此几乎一无所知。气味的科学研究对理解味道越来越重要，而味道对我们是否能够吃得健康至关重要。”

You explain that smell is a dual sense. It’s composed of orthonasal and retronasal smelling. What’s the difference between them?

问：“您解释说嗅觉是一种双重感觉。它包括正向鼻腔嗅觉和反向鼻腔嗅觉。这两者有何区别？”

Orthonasal is sniffing in. It happens when we sense perfume, something in the environment, or in the aromas of the food we are about to eat. Retronasal is called retro because it comes from the back of the mouth, and it’s the way we smell when we have food in our mouths. While we might not be aware of it, vapors that come from our food while we are breathing out stimulate cells in our nose. That is how smell contributes to flavor. We don’t realize it because all we usually notice is the mouth-feel, the textural quality of food.

答：“正向鼻腔嗅觉及吸进。如我们闻到香水、外界的某种事物或者我们准备吃的食物的香味。反向鼻腔嗅觉被称之为反向是因为其来自于口腔后部，我们用嘴吃饭时就是用这种方式感觉到气味。虽然我们不一定知道，但我们呼出的食物产生的气体会刺激鼻腔内的细胞。气味就是这样产生味道。我们没有认识到这一现象是因为我们通常只注意口腔的味觉和食物的质感。”

In the book, you discuss the ways in which smelling relates to the experience of flavor, and how it is different from tasting. You say that smell is “synthetic” while taste is “analytic.” That’s an interesting idea — could you elaborate on what you mean?

问：“在书中，您论述了嗅觉如何与味觉发生联系及两者的区别。您写道嗅觉是“合成的”，而味觉是“分解的”。这个观点非常有意思，您能够具体说一说这是什么意思么？”

It’s really simple. Taste is sweet, salt, sour and bitter — and umami, a meaty taste. The amazing thing is that when you have something in your mouth, you can taste whether it’s sweet, sour, bitter and so forth. This is analytic, because you analyze taste piece by piece, just as you would picking things up from a table. Each one is picked up separately. Smell is different because smell arises as a whole entity. It’s impossible to take the pieces apart. That’s why we call it synthetic: It’s synthesizing and bringing things together. And these are two aspects of sensation that are very important for the different senses.

答：“很简单。味觉是酸、甜、苦、咸和鲜（一种肉味）。神奇之处在于当你嘴里有东西的时候，你能尝出它是甜、是酸、是苦还是别的什么味道。这是因为你可以对其逐一进行分解，就像你从桌上一件件拿起东西来一样。每一样东西都是分开拿的。嗅觉则不一样，因为气味是一个整体，不可能将其一件件地区分开。这就是我们所说的合成，所有的东西是混合在一起的。这是感觉的两个方面，对不同的感觉来说极其重要。

One of the simpler concepts in olfaction is that smell molecules bind with receptor cells in our nasal cavity. After that things get a little bit more complicated as far as how information is relayed and processed within the brain.

嗅觉简言之就是气味分子与鼻腔中的受体分子结合。更复杂一点是关于大脑如何传递、处理信息。

Smell molecules are represented in the first stage in a part of the brain called the olfactory bulb. The olfactory bulb processes the information about smell in a way that is very similar to the way our retinas processes an image, or the way auditory parts of the brain represent musical patterns. It’s important to understand that smell is not completely unique in the way it stimulates the brain, because it processes information in a pattern, the same way other senses do. Only in olfaction is this sensory pattern represented in the frontal cortex, which is the most developed part of the human brain. All of the other senses have to be relayed forward in order to get to the cortex, so in mammals the sense of smell has privileged access to the front of the brain.

气味分子首先在大脑中被称之为嗅球的部分呈现。嗅球处理气味中所含信息的方式和视网膜处理图像的方式和大脑听觉部分呈现音乐模式的方式很相像。理解气味刺激大脑的方式并非独一无二很重要，因为大脑以模式处理信息，其他感觉也是如此。只有在嗅觉中，感觉模式在大脑中最发达的额皮质中呈现。其他所有的感觉在到达额皮质前都必须中转，所以哺乳动物的嗅觉可优先进入前脑（属于脑的最高层部分，是人脑中最复杂、最重要的神经中枢）。”

In another interesting part of the book, you mention studies that have shown marked variations in taste between some individuals. In some of these studies people have been labeled “supertasters.” How do their tasting ability and propensity differ from the rest of us?

问：“《神经美食法》的另一章节也很有意思，您提到研究表明个人的味觉有显著的差异。研究中有些人被称作“超级尝味者”。他们的尝味能力和尝味倾向和我们其他人有什么区别么？”

This has to do, partly, with how many taste buds they have. One of my colleagues has shown there is a correlation between having a high number of taste buds and a propensity to be sensitive to bitter taste. The more taste buds you have, the more likely you are to be a supertaster, and it’s caused by genetic differences. But keep in mind that this difference is specifically in the sense of taste. Taste contributes to flavor, but sometimes taste and flavor are used interchangeably, and they are not the same. There should be no ambiguity between “taste” — which is sweet, salty, sour or bitter — and flavor, which is a combination of olfactory sensations, tactile sensations and taste.

答：“这和他们有多少个味蕾有一定的关系。我的一位同事已经证明了味蕾多和对苦味敏感有关联。一个人味蕾越多，成为超级尝味者的可能性就越大，这是由基因不同引起的。但请记住这种不同特定于味觉。味觉影响味道，味觉和味道有时可以互换，但他们不一样。味觉和味道不存在模棱两可，味觉是酸、甜、苦、咸，而味道是嗅觉、质感和嗅觉的综合体。”

What role do texture and color play in taste?

问：“质感和颜色在味觉中起什么作用？”

You can be really fooled by the color of the food you are eating. I mention that you can fool people, and these include experienced wine tasters, into assuming that a white wine is a red wine, simply by dying it red. I think that’s a very good example of how color can be used to manipulate people. It’s something that gives us expectations about the flavor of what we are going to eat, and it’s very well understood by food companies, a point that Eric Schlosser makes in “Fast Food Nation.” You can bet that food companies are studying the colors that kids like to see on boxes of cold cereal and cans of soda.

答：“一个人确实可以被食物的颜色欺骗。我的意思是说你只需要将白葡萄酒染红，就可让别人，包括那些经验老到的品酒师，将一瓶白葡萄酒误认作红葡萄酒。我想这就是颜色如何影响人的极佳例子。颜色会使你对要吃的东西的味道有所期待。食品公司非常了解这一点，同样Eric Schlosser在《快餐帝国》中也阐述了这一观点。我可以打赌食品公司正在研究小孩喜欢看到什么颜色的冷麦片粥盒和什么颜色的苏打水罐。”

This might be pertinent, as Thanksgiving is coming right around the corner. What is “the buffet effect,” and how does it relate to some of our instinctual eating behaviors?

问：“这一点十分中肯，感恩节就要到了。什么是“冷餐会效应”？和我们本能的进食行为有什么关系？”

The buffet effect, also known as the cafeteria effect, relies on the assumption that if you have only one food in front of you, you will stop eating when you are full. But if someone brings you another plate with a different type of food on it, you are likely to keep eating. And it can go on like this indefinitely. You will eat far more with a variety of foods at one sitting than you would if you were eating only one dish. Fast-food companies know this. They sell a series of things in addition to the Big Mac. Thanksgiving is a good example of how with a dozen different dishes we just keep eating and eating. It’s a very real thing and people who are obese lack control over it.

答：“冷餐会效应也称作自助餐厅效应，即假设面前只有一样食物时，吃饱的人就不会再吃了。但如果端上来的盘子里有各色食物，人就可能继续吃下去，并且无限期地延续下去。食物花色品种很多时，一个人吃得要比只有一道菜时多得多。快餐公司清楚这一点。除了巨无霸汉堡，他们还卖系列套餐。感恩节12道菜的大餐也会让我们大吃特吃也是很好的例子。这是客观事实，肥胖的人缺乏对此的控制。”

Many parents tend to struggle at times with kids who are picky eaters. But in the book you discuss some of the ways in which taste and olfaction are relatively plastic. You mention that flavor preferences can change and young children can learn to enjoy certain types of foods from exposure. Do you have any advice for parents of picky eaters?

问：“许多父母总是为小孩挑食而头疼。但在《神经美食法》中，您写道味觉和嗅觉是相对可塑的。您还提到对味道的喜好是可以改变的，年幼儿童可以通过接触学会享受某种食物。您对小孩挑食的父母有何建议么？”

Well, I know from my own family experience that kids vary widely as eaters. And some aren’t just picky eaters but will refuse almost all foods except for a very narrow few. For kids, eating often means putting something in their mouth for the first time. That first sensation of something in your mouth can be quite aversive at first. And a child is more likely to feel that certain foods elicit a sensory quality that is unpleasant. This is where understanding how the brain creates the sensation of food, with multiple senses contributing, means that a therapist could begin to assess which sensory system is affecting how a child feels about an aversive food.

答：“恩......我自己的家庭经验是小孩吃东西的情况各有不同。有些人不是挑食，而是除了有限的几种食物什么都不吃。对小孩来说，吃东西通常意味着第一次将某种东西放进嘴里。如果放进嘴里的东西一开始感觉就很差，那么这个小孩很可能就会觉得这种食物总是感觉不怎么样。这便是对大脑如何凭借多种感觉感知食物的理解，也就意味着治疗师可以开始评价哪一种感官机制如何产生影响，从而让小孩对某种食物感觉不好。”

A lot of the topics in the book made me think about my own personal relationship to food and taste. I don’t know if you’ve ever experienced this, but sometimes I’ll go to a restaurant and notice that although they have Heinz ketchup bottles on the table, the first taste will clearly determine that they’ve filled the Heinz bottles with an impostor brand of ketchup. It infuriates me, and I think it undermines exactly what you lay out in your book: that the human propensity for taste and olfaction is actually much more sophisticated than we might assume. Can you speak to this?

问：“《神经美食法》一书中的许多话题让我思考自己与食物和味道的关系。我不知道你是否有这样的经历。有时候去一家餐厅，虽然我看到桌上有亨氏番茄酱瓶，但尝了一口之后便确定他们在瓶里装了冒牌的番茄酱。这让我极为恼火，我想这无疑削弱了您在书中的论述，即人类味觉和嗅觉的倾向实际上要比设想的复杂的多。您可以对此说几句么？”

I haven’t experienced that, but it makes sense. I think one of the simplest ways of giving more credit to smell in flavor is the simple nose-pinch test. You pinch your nose and put a piece of candy or food on your tongue and ask what the flavor is. With their nose pinched, most people will be able to tell that it tastes sweet and that is all. Once you un-pinch your nose, the whole flavor of the food is able to travel to the brain, and that is all due to smell. As the subject breathes out, air goes from the back of the mouth up to the nose. This is a simple experiment that you can do around your dinner table. It gives you a completely new appreciation of where your sense of flavor is coming from. People use their sense of smell to get more pleasure out of the food that they are eating.

答：“我没有这样的经历，但这的确说得通。我想一种简单的让人相信味道中气味的方法就是捏鼻子测试。你捏住自己的鼻子，放一粒糖之类的东西在自己的嘴里，然后问自己是什么味道。因为捏住了鼻子，大多数人会说味道很甜，仅此而已。一旦你放开自己的脖子，它所有的味道会进入你的大脑，这就是气味的缘故。在呼气时，空气从口腔后部升至鼻腔。这是一个晚餐时可以做的简单试验。这将让你对味道的感受来源有全新的理解。人们用嗅觉从所吃食物中获得更多的愉悦。”