Peanuts cause allergic reactions chiefly when they have been dry-roasted, a study suggests.
Tests carried out by Oxford University researchers found that eaten raw the nuts had little effect on the immune system.
They are now working on safe, dry-roasted peanuts to help prevent an allergy that affects one in 50 children.

‘We did a simple experiment and found that the mice fed the dry-roasted proteins got an immune response indicative of allergy,’ said researcher Quentin Sattentau.
‘Whereas the mice fed the raw peanut proteins didn’t or did to a much lesser extent.’
The result was the same whether the mice were fed peanut protein or had it rubbed into broken skin – both ways in which peanuts are thought to trigger allergies in humans.
Professor Sattentau added: ‘This is the first time, to our knowledge, that a potential trigger for peanut allergy has been directly shown.’
The finding helps explain why peanut allergy is much more common here than in the Far East, where the nuts are more commonly eaten raw, boiled or fried.
It is believed that the process of dry-roasting involves temperatures high enough to change the peanut’s chemistry in a way that confuses the immune system and leads to allergic reactions.
It will be some years before safer dry-roasted peanuts are on supermarket shelves and the complex nature of the immune system means that those who already have a peanut allergy are unlikely to be helped. While the majority of reactions are mild, nut allergy can trigger a life-threatening anaphylactic shock.
The Oxford team said it would be premature for people to avoid the nuts because of their research, published in the Journal of Allergy and Clinical Immunology.



參考譯文：
用文物界的行話來說，牛津大學的科學家這叫“撿了一個大漏”？

花生是歐美國家最常導致過敏的食物之一，影響到2%的兒童，有時還可以發生足以致命的過敏性休克，而在世界其他地區，花生過敏卻極其罕見。

過敏和臨床免疫學雜志發表了來自牛津大學的一項非常簡單的實驗，為困擾人們的這個“難題”給出了可能的答案。

研究人員發現，通過皮膚下注射、破損的皮膚、或者直接導入胃中這三種途徑，讓小鼠接觸干焙花生蛋白更易引發過敏反應，而換成生花生蛋白則沒有或極少引發過敏反應。

這個結果提示，干焙花生是造成花生過敏的關鍵因素。研究人員認為，歐美地區制作花生時干焙溫度高到足以引起花生蛋白質發生化學反應形成了能夠“愚弄”人體免疫系統的成分，引發過敏反應。而在亞洲等很多地區，人們更習慣于生吃、水煮或油炸。

雖然需要更深入的研究，但是這項簡單實驗的發現可能有助于解決花生過敏問題，可能屬于小實驗解決大問題的案例。

來源：http://www.dailymail.co.uk/health/article-2764618/Dry-roasted-peanuts-worst-allergies-Findings-help-scientists-develop-nuts-prevent-reactions.html