2014/4/12 「啤酒配烤肉 降低罹大腸癌機會」

啤酒配烤肉　降低罹大腸癌機會

摘錄自：天下雜誌 經濟學人電子報                        2014/4/11

2014-04-10 Web only 作者：經濟學人

圖片來源：flickr.com/photos/kalleboo/

火烤讓肉更加美味，但這樣的美味有其代價，因為火烤會製造名為多環芳香烴（PAH）的分子；它會傷害DNA，進而增加食用者罹患大腸癌的機會。對那些認為烤肉是夏日美事之一的人來說，這實在太可惜了。不過，由波爾圖大學的費爾拉（Isabel Ferreira）帶領的研究團隊認為，他們找到了避開這個問題的方式。他們建議，烤肉時應該搭配啤酒。

費爾拉博士在論文中解釋道，這個讓人歡喜的建議，出自十分嚴謹的研究。火烤所製造的PAH，源自於名為自由基的分子，自由基則是由脂肪和蛋白質在火烤等高溫烹調下形成。因此，阻止PAH形成的方式之一，就是以抗氧化化學物消除自由基。啤酒富含抗氧化物，也就是在烘培大麥時形成的梅納汀；因此，費爾拉博士團隊準備好啤酒醃汁、買了些牛排之後，便來到烤架前方。

其中一種醃汁是以皮爾森淡啤酒為基底，第二種則是以黑啤酒為基底。由於黑啤酒中的梅納汀含量高於淡啤酒，費爾拉博士的假說認為，以黑啤酒醃製的牛排，PAH形成量會低於淡啤酒醃製的牛排，後者的PAH量則會低於沒有醃製過的控制組牛排。

結果確實如此。烹調之後，未醃製的火烤牛排每公克平均含有21毫微克（十億分之一克）的PAH；以皮爾森啤酒醃製的牛排平均為18毫微克，以黑啤酒醃製的牛排平均僅10毫微克。既好吃又健康，正合所需。（黃維德編譯）

©The Economist Newspaper Limited 2014

經濟學人英文原文

The Economist

Beer and barbecues

A marriage made in heaven

 By The Economist

 From CommonWealth Magazine

 Published: April 10, 2014

Apr 5th 2014 | From the print edition

To reduce the health risk of barbecuing meat, just add beer

GRILLING meat gives it great flavour. This taste, though, comes at a price, since the process creates molecules called polycyclic aromatic hydrocarbons (PAHs) which damage DNA and thus increase the eater's chances of developing colon cancer. For those who think barbecues one of summer's great delights, that is a shame. But a group of researchers led by Isabel Ferreira of the University of Porto, in Portugal, think they have found a way around the problem. When barbecuing meat, they suggest, you should add beer.

This welcome advice was the result of some serious experiments, as Dr Ferreira explains in a paper in the Journal of Agricultural and Food Chemistry. The PAHs created by grilling form from molecules called free radicals which, in turn, form from fat and protein in the intense heat of this type of cooking. One way of stopping PAH-formation, then, might be to apply chemicals called antioxidants that mop up free radicals. And beer is rich in these, in the shape of melanoidins, which form when barley is roasted. So Dr Ferreira and her colleagues prepared some beer marinades, bought some steaks and headed for the griddle.

One of their marinades was based on Pilsner, a pale lager. A second was based on a black beer (type unstated). Since black beers have more melanoidins than light beers—as the name suggests, they give it colour—Dr Ferreira's hypothesis was that steaks steeped in the black-beer marinade would form fewer PAHs than those steeped in the light-beer marinade, which would, in turn, form fewer than control steaks left unmarinated.

And so it proved. When cooked, unmarinated steaks had an average of 21 nanograms (billionths of a gram) of PAHs per gram of grilled meat. Those marinated in Pilsner averaged 18 nanograms. Those marinated in black beer averaged only 10 nanograms. Tasty and healthy too, then. Just what the doctor ordered.

©The Economist Newspaper Limited 2014