菜籽油、苧麻油、紅棕櫚油、南瓜油……突然橄欖油在超市的貨架有了許多競爭對手，但它們是否比我們一貫喜歡用的橄欖油更健康、更美味呢？羅伯特.哈德森用試驗揭開了謎底。

It was a day like any other, and I was in the super-market, reaching confidently for a bottle of extra virgin olive oil. I hadn't looked at the oil shelf properly for five years - olive oil tastes good, it's part of the famously healthy Mediterranean diet, so what is there to think about? Suddenly though, my eye was caught by a dusky bottle of cold-pressed rapeseed oil. Next to it, I noticed the line of hemp, grapeseed, red palm and canola oils, all smartly packaged, all making strident health claims. I found myself twisting in bewilderment.

Lately it seems the oil shelves have been invaded by new varieties. All naturally claim to be delicious, and, because olive oil's success has been fuelled by its perceived health benefits, they all claim to be great for you too. So, for example, Hillfarm Extra Virgin Rapeseed oil trumpets its "Delicious light nutty flavour" before adding that it is "very low in saturated fat, contains Omega 3, 6 + 9 and is free from artificial preservatives." It is "an ideal oil for those concerned with their health and wellbeing."

So, had my knee-jerk reliance on olive oil blinded me to a better, healthier, tastier way of life? After all, Omega 3 is important to the circulation and brain, and Omega 6 helps skin and hair (although excessive amounts have been linked to heart disease); both are found in rapeseed, avocado, hemp, pumpkin and walnut oils. Omega 9 is not essential. It has fewer demonstrated health benefits, and our bodies produce it from other unsaturated fats. Significantly, olive oil is full of Omega 9, but low in the other two. So do we need to switch?

Dietitian Ursula Arens says no. "These are important nutrients, but for essential fatty acids, there is no doubt that fish oils are the star. Vegetarians might need to consider getting some of their Omega 3 from vegetable oils, but they would need to eat large amounts."

In fact, quantity is key. When it comes to health claims Arens says "it's highly unlikely that you will eat these oils in amounts that will make any difference." Many contain useful nutrients - vitamin E in avocado oil and plum seed oil, a wide range of amino acids in hemp oil - but, "if you're using these in dressings once in a while, then all this is pretty irrelevant, nutritionally."

The health arguments considered, I embarked on a taste test with Allegra McEvedy and her friend, Charles Carey, who has been importing oils for more than 20 years. First came a mouth-watering demonstration of the distinction between refined walnut oil and a cold-pressed "virgin" walnut oil from the A L'Olivier mill in Poitiers. The dry, rich taste of the nut glowed warmly on the tongue. (In this context, "virgin" means that the oil is not mixed with any additive , where a virgin oil must have an acidity of less than 3%.)

Carey then moved on to a rapeseed oil. Most vegetable oil sold in the UK is actually made from rapeseed, but it's become fashionable to lose that general label, and sell these oils as extra virgin rapeseed oil, or cold-pressed varieties.

"I have to laugh," says Charles. "These descriptions have legal standing for olive oils, but rapeseed guys are mainly using them because they sound good." We try an organic rapeseed oil from Brittany, called Troustain Barville, which Allegra describes as "grassy" and Charles calls "brassica-ish". It's not unpleasant, but it's difficult to see why you would choose it over the alternatives.

We discuss hemp oil, which, as you might expect, tastes grassy, and a bit overpowering, and palm oil, which is basic to much African and West Indian cookery, but is a bit too rich for our palates. Allegra regards avocado oil as "pointless. If you want something oily which tastes of avocado, eat an avocado."

Next up are two oil wildcards: plumseed and coffee. It's claimed that plum seed oil can be used in salad dressing, but, on trying it, the idea seems slightly bizarre. The taste is less fierce than the overpowering marzipan bouquet suggests, but still Allegra says, "Crikey! This is like instant frangipane! You could use it as a baking ingredient, I suppose."

As for the coffee oil - the result of olives and coffee beans being pressed together by the Spanish olive oil producer Vea - again it is pungent, almost acrid. The bottle comes with a hopeful collection of recipes, many of which seem to infer that coffee and seafood are natural bedfellows: shrimps in a mint coffee sauce and sea bream with vinaigrette and coffee oil, for instance. A couple, including ice cream, and an endive and nut salad, sound OK, but really, would you bother?

"Frankly, no," says Allegra, explaining that she sticks to "groundnut oil for Asian food, and nice walnut oil is great in a dressing or for adding depth to stews". She's impressed when we try an A L'Olivier grapeseed oil, which causes her to exclaim "Oh, this is really fresh!", before Charles explains that he uses it for mayonnaise."I can see a use for that," she agrees, "but I'm not convinced by the others."

Me neither. As Arens says, the nutritional benefits are, for the most part, negligible, and while you could find occasional use for some of these oils - potatoes roasted in virgin rapeseed oil are fresh and light - none could replace olive oil for kitchen versatility. My head may have been briefly turned, but I'll stick to my old favourite.

那天，在超市里，像往常一樣，我滿懷信心地把手伸向放特級初榨橄欖油的貨架。實際上在過去的五年里我基本上沒關注過放食用油的貨區，因為橄欖油味道很好，它是聞名的地中海健康飲食的一部分，所以有什么好猶豫的呢？但是，突然我的眼睛被一瓶顏色較深的冷榨菜籽油吸引。在它旁邊，我注意有一溜兒的苧麻油、葡萄籽油、紅棕櫚油和油菜籽油，它們包裝都很精美，瓶身上都有食用如何如何健康的描述。這時我發現自己很難抉擇了。

最近似乎食用油貨架已被新品種侵入了。所有的油都聲稱天然、美味，而且由于被認為對健康有益促進了橄欖油的成功，他們也都聲稱自己最適合你。比如，Hillfarm特級初榨菜籽油宣傳自己“低飽和脂肪，含有歐米加3 、6 、9、不含人工防腐劑”，鼓吹自己“有怡人的清新堅果氣息”，是“那些關注自身健康和幸福人士的理想食用油。”

那么，是潛意識依賴橄欖油使我無視一個更美好、更健康、更美味的生活方式嗎？畢竟，歐米加3對血液流通和大腦很重要，歐米加6有助于皮膚和頭發（盡管攝入過量有患心臟病的風險）；它們在菜籽油、鱷梨油、苧麻油、南瓜油、核桃油里都有。歐米加9是非必需的，它很少表現對健康的好處，我們的身體能從其他不飽和脂肪中自己合成。值得注意的是，橄欖油富含歐米加9 ，但其他兩個的含量較低，所以我們需要換其他油嗎？

營養師烏爾蘇拉.阿倫斯說不用。“這些都是重要的營養物質，但對于必需脂肪酸，毫無疑問，魚油應排在首位。素食主義者可能需要考慮從植物油中攝取一些歐米加3，但他們將需要吃大量的油分。”

事實上，數量是關鍵。說到健康宣傳，阿倫斯說，“你將吃的這些油的數量不可能有任何區別。”許多都包含有用的營養素——鱷梨油和梅子籽油里的維生素E，苧麻油里有各種各樣的氨基酸——但是，“如果你只是做為飲食的輔料偶爾用上一點點，這跟營養沒什么相干。”

考慮到對健康的的爭議，我和艾麗格拉.麥克伊韋迪以及她做了二十多年食用油出口生意的朋友查爾斯.凱里著手進行了口味測試。首先我們做了令人垂涎三尺的示范，以顯示精制核桃油和來自波亞提爾橄欖油小鎮的冷榨初級胡桃油的區別，濃濃的果香味在舌間微微蕩漾。（在本文中，“初榨”指沒有與任何添加劑混合，初榨的油必須含不少于3%的酸度。）

然后凱里接著實驗菜籽油，英國大多數植物油產品實際上是由菜籽油制成的，但把這些油作為特級初菜籽油或冷榨油品出售，不用菜籽油標簽成為時髦的事。

“我不得不笑了，”凱里說，“對于橄欖油的那些描述有法定依據，但造油菜籽的那些人主要是利用它們，因為這些文字聽起來不錯。”我們試驗了來自布列塔尼的叫Troustain Barville的有機菜籽油，艾麗格拉描述它為“綠色的”，凱里說它是甘藍雜交而成。結果令人不太愉快，但很難理解為什么人們會從很多種類的油中選擇它。

我們討論了苧麻油，像你想象的那樣，有植物的香味，有點讓人無法抗拒；棕櫚油，這是非洲和西印度烹飪的基本用油，但對我們的味蕾來說它過于濃烈了，艾麗格拉認為“鱷梨油是最不靠譜的，如果你想要有點油膩，口味又像鱷梨，那就吃個鱷梨吧。”

接下來是兩個榨油的原料：梅子籽和咖啡豆。據說，梅籽油可用于沙拉醬，但我們沒試過，這個想法聽起來有點詭異。味道跟杏仁糖果相比，要溫和地多，但艾麗格拉說，“這就像即時杏仁！我猜你可以用它作烘焙配料。”

至于咖啡豆，由于西班牙橄欖油生產商Vea同時將橄欖和咖啡豆一起壓榨，也是富有刺激性，幾乎可以說是辛辣。瓶身上附有收集來的各種菜譜，其中許多似乎推斷咖啡和海鮮是天然的伙伴，比如蝦與薄荷咖啡醬、鯛魚與辣醬和咖啡油。一些配著吃的食物，包括冰淇淋，菊苣和螺母沙拉，聽上去不錯，但你會不會真的嘗試呢？

“坦率地說，不會，”艾麗格拉說，她堅持“花生油用來吃亞洲食品，上乘的胡桃油是調味品的首選，能使肉燉的更好，”給她留下深刻印象的是我們試驗的波亞提爾橄欖油小鎮的葡萄籽油，在查爾斯解釋他用它來做蛋黃醬之前，她不由驚呼“啊，真的很新鮮！”“我可以用它來做蛋黃醬，但不確定會用來做其他的食物。”

我也不會，就像阿倫斯說的，在大多數情況下，營養好處的可以忽略不計，但你可以偶爾使用一下這些油——用初榨的菜籽油炸出的土豆會更新鮮酥脆——但沒有任何油可以替代在廚房里廣泛使用的橄欖油。我的大腦短暫地拐了個彎，最終還是堅持我的舊愛——橄欖油！