蔬菜如何烹饪会更合理

菜是我们日常饮食中必不可少的重要内容，但你知道如何才能保存甚至提升蔬菜自身的营养价值吗?这一切的关键在于烹饪方法，一起来看看科学家们的建议吧!

Food experts say it’s all too easy to lose the medical benefits of vegetables by boiling or freezing their nutrients away. Here, we show you the best ways to prepare your vegetables—and how you can maximise nutrient levels through cooking.

GENERAL RULES FOR COOKING VEGETABLES

There are two ways that vegetables lose vitamins and minerals, says Anna Denny, a scientist at the British Nutrition Foundation. “The first is when nutrients leachinto water when boiled. The second is when they are broken down through heat. Obviously it is difficult not to heat vegetables, so the key is to heat them for a brief amount of time—two to three minutes at most.” If the vegetables are still crunchy when you eat them, then they’re probably still packed with nutrients. If they are tender and soft, they’re not.

Denny says that the more delicate the vegetable, the less you should cook it. “Spinach, for example, breaks down very quickly. You can cook it into nothing in no time at all.”

The best way to cook a vegetable is to steam it in a very small amount of water. Make sure that the water is hot to start with, so that the vegetables don’t have to be in the steamer for very long.

Don’t be afraid to use the microwave. It may be seen as the most evil apparatus in the kitchen, but microwaving is far better than boiling. Again, use only a tiny amount of water and heat for no more than three minutes.

Stir-frying is a good way to cook vegetables. Don’t use too much fatty oil.

The only vegetable you should boil is the potato, says Denny. If you absolutely have to boil your vegetables, you can consume their leached-out nutrients by keeping the water and using it to make fresh soup or stock.

TOMATOES

“Fresh isn’t always best,” says Frankie Phillips of the British Dietetic Association. “Lycopene, the antioxidant that has been found to lower the risk of some cancers, notably prostate, is absorbed better from processed tomatoes than fresh ones. It’s thought that when they are broken down, more of the lycopene is released.” To that end, it’s best to puree your tomatoes.

PEPPERS

Phillips advises lightly stir-frying peppers in any type of oil for between two and three minutes. This is because the fat in the oil helps the beta-carotene in peppers to absorb. Beta-carotene is an antioxidant which has been found to boost immunity, protect the eyes and fight cancer-causing free radicals.

GARLIC

It’s all in the preparation with garlic. Researchers at Penn State University in America found that heating, roasting and microwaving garlic immediately after crushing it destroys the enzyme that produces a kind of cancer-fighting compound. However, leaving the chopped or crushed garlic to stand for 10 minutes preserves the enzyme.

BROCCOLI

When buying broccoli, make sure it is uniform in colour to ensure freshness. Stems take slightly longer to cook than florets, so put them on a minute earlier. Don’t get rid of the leaves because they are rich in nutrients, too. It is thought that slicing broccoli helps to release some of its nutrients so they are more readily absorbed by the body.

Vocabulary

antioxidant 抗氧化剂

apparatus 设备，器具

beta-carotene β-胡萝卜素

boost 增强

break down 损坏

broccoli 花椰菜，球花甘蓝

chop 剁，砍

consume 吃，喝

crunchy 发嘎吱嘎吱声的，脆的

ensure 确保，确定

enzyme 酶

floret 小花

free radical 自由基，游离基

immunity 免疫力

leach 过滤，滤掉

lycopene 番茄红素

maximize 最大限度地利用(某事物)

nutrient 养分，营养物

processed 加工处理过的

prostate 前列腺

puree 把……捣压成酱(泥、糊或羹)

slice 切

spinach 菠菜

steamer 蒸锅

stem (植物的)茎

stir-frying 炒

stock 原汤，汤汁

uniform 全部相同的，一致的