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.



参考译文：
用文物界的行话来说，牛津大学的科学家这叫“捡了一个大漏”？

花生是欧美国家最常导致过敏的食物之一，影响到2%的儿童，有时还可以发生足以致命的过敏性休克，而在世界其他地区，花生过敏却极其罕见。

过敏和临床免疫学杂志发表了来自牛津大学的一项非常简单的实验，为困扰人们的这个“难题”给出了可能的答案。

研究人员发现，通过皮肤下注射、破损的皮肤、或者直接导入胃中这三种途径，让小鼠接触干焙花生蛋白更易引发过敏反应，而换成生花生蛋白则没有或极少引发过敏反应。

这个结果提示，干焙花生是造成花生过敏的关键因素。研究人员认为，欧美地区制作花生时干焙温度高到足以引起花生蛋白质发生化学反应形成了能够“愚弄”人体免疫系统的成分，引发过敏反应。而在亚洲等很多地区，人们更习惯于生吃、水煮或油炸。

虽然需要更深入的研究，但是这项简单实验的发现可能有助于解决花生过敏问题，可能属于小实验解决大问题的案例。

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