经济学人47:论鹅肝 多少是个度

 　　Science and Technolgy

　　科技

　　Foie-gras production

　　论鹅肝

　　How much is too much?

　　多少是个度

　　Why some duck livers are delicious, and others nasty

　　为什么有的鹅肝是珍馐，有的却让人恶心

　　FOIE GRAS is one of the most controversial dishes on earth. To protagonists¹, it is simply the finest foodstuff² that exists. To those opposed, it is a product of cruelty that is not far short of criminal. The overfeeding of ducks and geese, so that their livers bloat to between six and ten times their normal size and take on a buttery consistency³ valued by gourmets⁴, exploits the ability of these birds to store large amounts of calorie-rich fat, which was needed to propel them on the long migrations⁵ that their wild ancestors would routinely have undertaken. The moral argument over the way foie gras is produced (by feeding the birds with grain, through a tube or a funnel) turns on whether this is merely the permissible⁶ exaggeration of a natural inclination⁷, or is tantamount to abuse. Intriguingly⁸, a newly published piece of research on foie-gras production suggests the quality of the product depends on exactly the same distinction.

　　鹅肝是这世上最富争议的食物之一。支持鹅肝的人说它是最美的珍馐；而反对者则认为制作鹅肝与犯罪无异。鸭鹅被过度灌食后，肝脏将变为正常水平的6至10倍并呈现出美食家所推崇的黄油状，肝脏贮存脂肪的能力被充分挖掘。鸭鹅的祖先需要定期长途迁徙，而这些脂肪可以为其提供充足的能量。制作鹅肝*（用管子或漏斗对鸭鹅灌饲谷物）涉及一个道德问题：这种做法究竟是在可接受的范围内将动物自身的功能发挥至极致，还是一种虐待行为。有意思的是，最近发表的一篇关于制作鹅肝的研究认为，鹅肝的质量取决于这一问题。

　　From the chef's point of view, one of the disturbing things about foie gras is how variable it is. Some livers, when cooked, retain their fat and thus their rich flavour. Others lose fat when heated and end up tasting terrible. To try to work out why, Caroline Molette, a biologist at the University of Toulouse, did some experiments. Her results, just published in the Journal of Agricultural and Food Chemistry, suggest that the difference is whether the liver in question is truly healthy or not.

　　在厨师看来，鹅肝的麻烦事之一是质量参差不齐。有些肝脏烹饪后还保留着脂肪、油腻感十足。有些肝脏在加热后脂肪就没了，相当难吃。为了搞清楚其中缘由，法国图卢兹大学（University of Toulouse）的生物学家Caroline Molette进行了实验，并将结果发表于《农业与食品化学杂志》（Journal of Agricultural and Food Chemistry）。她认为其中差别在于所用肝脏健康与否。

　　Dr Molette and her colleagues raised 150 male mule⁹ ducks (a cross between Pekin and Muscovy ducks that is often used to produce foie gras) for 13 weeks in standard poultry-house conditions and then transferred them into individual enclosures. For a further 12 days the birds were fattened¹⁰ up with a mash¹¹ of grain and flour—the usual procedure for enlarging their livers. They were then slaughtered¹², their livers removed, and those livers immediately trimmed of their blood vessels¹³ and chilled for six hours.

　　Molette博士与其同事将150只雄性杂交鸭（北京鸭与疣鼻栖鸭的杂交种，常用于生产鹅肝）在家禽饲养场标准条件下养殖13周，然后转入单独的笼子中。在之后的12天，用谷物和面粉的混合物灌饲鸭子——这是让肝脏变大的常用步骤。然后处死鸭子，取肝脏，快速剔除血管，冷藏六小时。

　　So far, so normal. But instead of cooking the whole things, Dr Molette removed a 200-gram sample from each liver (an average liver weighed 550 grams) and put the rest in cold storage. She then placed each sample into a jar with a bit of salt and pepper, and cooked it for an hour. As she expected, some livers released a lot of fat when cooked while others released little. Armed with this information, she was able to turn her attention back to the uncooked sections of the livers and see if she could find any systematic¹⁴ chemical differences between them.

　　到此阶段，一切正常。然而Molette 博士并没有使用整个肝脏，而是从每份肝脏（均重550克）中取200克作为样品，其余冷藏。她将每个样品分别放置在罐子中，加入少许盐和胡椒，烹饪半小时。正如她所料，烹饪时有些肝脏释放出大量脂肪，而有些却不是。获得这一信息后，她就将目光转向至还没处理的那部分肝脏，她想知道这二者之间是否存在系统性化学差异。

　　Using a combination of electrophoresis (which sorts proteins according to their size and electrical properties) and mass spectrometry (which sorts fragments of those proteins according to their weight), she was able to do just that. The upshot was that the fat-retaining livers were rich in a variety of proteins known to help the body digest and store food. In the fat-shedding livers, by contrast, she found high concentrations of a protein called fatty-acid-binding-protein 4. In a human liver, this would be a marker of disease. Put simply, the fat-retaining livers are healthy while the fat-shedding ones are not.

　　Molette 博士使用电泳（根据蛋白质的分子大小和电荷差异，将蛋白质分离）和质谱（根据分子量将蛋白碎片分离）测定来进行实验。结果发现，保留脂肪的蛋白质富含多种有助于人体消化和贮存食物的蛋白质。相比之下，她在没有脂肪的肝脏中发现了一种名为脂肪酸-结合蛋白4的蛋白质，且浓度很高。在人类肝脏中，这种蛋白是一种疾病指示物。简单的说，保留脂肪的肝脏是健康肝脏，而没有脂肪的肝脏不健康。

　　Both sides of the debate, then, are right. Foie-gras production can be a form of abuse but is not necessarily so, for an enlarged liver can still be healthy. The question is, how do you draw the line?

　　所以，讨论双方说的都对。生产鹅肝可以是一种虐待行为，但也可以不是，因为超大肝脏仍然可以是健康的。问题在于，分界线在哪里?

　　Dr Molette's ducks were all treated similarly, and their livers were of more or less the same size (certainly, the fat-shedding ones were not systematically¹⁵ heavier). The search is therefore on for some way to tell in advance which animals will respond positively¹⁶ to extra helpings¹⁷ and which will not. That knowledge would help farmers, gourmets and animal-lovers alike.

　　Molette博士的鸭子，处理方法相似，肝脏大小差不多一样（当然，没有脂肪的肝脏总体来说不会更重）。所以，这项研究可以从某种角度提前告诉我们：哪些动物对过度喂食反应良好，哪些不是。这一点也可帮助农民、美食家、以及动物爱好者。

1 protagonists   

n.（戏剧的）主角( protagonist的名词复数 )；（故事的）主人公；现实事件（尤指冲突和争端的）主要参与者；领导者

参考例句：

• Mrs Pankhurst was one of the chief protagonists of women's rights. 潘克赫斯特太太是女权的主要倡导者之一。 来自辞典例句
• This reflects that Feng Menglong heartily sympathized with these protagonists. 这反映出冯梦龙由衷地同情书中的这些主要人物。 来自互联网

2 foodstuff   

n.食料，食品

参考例句：

• They handled groceries and foodstuff.他们经营食品杂货。
• Construct a international foodstuff promotion and exhibition trade center.建成国际食品会展经贸中心。

3 consistency   

n.一贯性，前后一致，稳定性；(液体的)浓度

参考例句：

• Your behaviour lacks consistency.你的行为缺乏一贯性。
• We appreciate the consistency and stability in China and in Chinese politics.我们赞赏中国及其政策的连续性和稳定性。

4 gourmets   

讲究吃喝的人，美食家( gourmet的名词复数 )

参考例句：

• The food here satisfies gourmands rather than gourmets. 这里的食物可以管饱却不讲究品质。
• Here is another example: "Western gourmets are sold on Peking Duck." 这里再举一个例子：“西方美食家已对北京烤鸭极有兴趣。”

5 migrations   

n.迁移，移居( migration的名词复数 )

参考例句：

• It foundered during the turmoils accompanying the Great Migrations. 它在随着民族大迁徙而出现的混乱中崩溃。 来自辞典例句
• Birds also have built-in timepieces which send them off on fall and spring migrations. 鸟类也有天生的时间感应器指导它们秋春迁移。 来自互联网

6 permissible   

adj.可允许的，许可的

参考例句：

• Is smoking permissible in the theatre?在剧院里允许吸烟吗？
• Delay is not permissible,even for a single day.不得延误，即使一日亦不可。

7 inclination   

n.倾斜；点头；弯腰；斜坡；倾度；倾向；爱好

参考例句：

• She greeted us with a slight inclination of the head.她微微点头向我们致意。
• I did not feel the slightest inclination to hurry.我没有丝毫着急的意思。

8 intriguingly   

参考例句：

• Intriguingly, she gave to the music a developed although oddly malleable personality. 最神奇的是，她的音乐具有成熟却又很奇怪地极富可塑性。 来自互联网
• Intriguingly, the patients brains were riddled with tangles, but not amyloid plaques. 有趣的是，患者的大脑中充满了各缠结，但并没有粉斑。 来自互联网

9 mule   

n.骡子，杂种，执拗的人

参考例句：

• A mule is a cross between a mare and a donkey.骡子是母马和公驴的杂交后代。
• He is an old mule.他是个老顽固。

10 fattened   

v.喂肥( fatten的过去式和过去分词 )；养肥（牲畜）；使（钱）增多；使（公司）升值

参考例句：

• The piglets are taken from the sow to be fattened for market. 这些小猪被从母猪身边带走，好育肥上市。
• Those corrupt officials fattened themselves by drinking the people's life-blood. 那些贪官污吏用民脂民膏养肥了自己。 来自《现代汉英综合大词典》

11 mash   

n.麦芽浆，糊状物，土豆泥；v.把…捣成糊状，挑逗，调情

参考例句：

• He beat the potato into a mash before eating it.他把马铃薯捣烂后再吃。
• Whiskey,originating in Scotland,is distilled from a mash of grains.威士忌源于苏格兰，是从一种大麦芽提纯出来的。

12 slaughtered   

v.屠杀，杀戮，屠宰( slaughter的过去式和过去分词 )

参考例句：

• The invading army slaughtered a lot of people. 侵略军杀了许多人。 来自《简明英汉词典》
• Hundreds of innocent civilians were cruelly slaughtered. 数百名无辜平民遭残杀。 来自《简明英汉词典》

13 vessels   

n.血管( vessel的名词复数 )；船；容器；（具有特殊品质或接受特殊品质的）人

参考例句：

• The river is navigable by vessels of up to 90 tons. 90 吨以下的船只可以从这条河通过。 来自《简明英汉词典》
• All modern vessels of any size are fitted with radar installations. 所有现代化船只都有雷达装置。 来自《现代汉英综合大词典》

14 systematic   

adj.有系统的，有计划的，有方法的

参考例句：

• The way he works isn't very systematic.他的工作不是很有条理。
• The teacher made a systematic work of teaching.这个教师进行系统的教学工作。

15 systematically   

adv.有系统地

参考例句：

• This government has systematically run down public services since it took office.这一屆政府自上台以来系统地削减了公共服务。
• The rainforest is being systematically destroyed.雨林正被系统地毀灭。

16 positively   

adv.明确地，断然，坚决地；实在，确实

参考例句：

• She was positively glowing with happiness.她满脸幸福。
• The weather was positively poisonous.这天气着实讨厌。

17 helpings   

n.（食物）的一份( helping的名词复数 )；帮助，支持

参考例句：

• You greedy pig! You've already had two helpings! 你这个馋嘴！你已经吃了两份了！
• He had two helpings of pudding. 他吃了两客布丁。 来自《现代汉英综合大词典》