In short
- Blanching means boiling vegetables very briefly and then putting them straight into ice water.
- It locks in colour, bite and vitamins and stops the cooking immediately.
- You mainly blanch to prep vegetables, freeze them or serve them crisp.
- Leafy greens need only seconds, firm vegetables a few minutes.
Blanching sounds like something for chefs, but it is one of the simplest techniques you have at home. You use it to keep vegetables bright green and crisp, or to get them ready for the freezer. Here is what it is and how to do it.
What is blanching?
Blanching means cooking food very briefly in boiling water and then plunging it straight into ice water. That cold shock stops the cooking at exactly the right moment. The result is vegetables that are cooked enough to work with, but still firm and brightly coloured.
How do you blanch vegetables step by step?
- Bring a large pan of water to the boil and add a pinch of salt.
- Get a bowl of ice water ready.
- Add the vegetables to the boiling water as soon as it is bubbling hard.
- Cook briefly: from a few seconds for leafy greens to a few minutes for firm vegetables.
- Lift the vegetables out and put them straight into the ice water.
- Let cool, drain and pat dry.
When do you use blanching?
Blanching is handy when you want to prep vegetables ahead or freeze them: it switches off enzymes that would otherwise spoil colour, flavour and bite in the freezer. That keeps frozen vegetables good for longer, as the National Center for Home Food Preservation also confirms. You also use it to serve vegetables crisp and bright green, to keep the bite for a stir-fry, or to easily remove the skin from tomatoes, for example.
How long should you blanch?
The time depends on the vegetable: the firmer it is, the longer it takes. Leafy greens are done in seconds, while firm vegetables need a few minutes.
| Vegetable | Blanching time |
|---|---|
| Leafy greens (spinach, endive) | a few seconds |
| Broccoli or cauliflower (florets) | 2 to 3 min |
| Green beans | 2 to 3 min |
| Carrot (in pieces) | 3 to 4 min |
Why plunge into ice water?
The ice water stops the cooking immediately, so the vegetable does not keep cooking in its own heat. That keeps the colour bright green and the bite firm. Skip this step and the vegetable still turns soft and dull, even out of the pan.
The right pan for blanching
Use a large pan so the water comes back to the boil quickly when the vegetables go in, and get a bowl of ice water ready. For larger amounts, use a large pan. Blanching is often the first step before frying or stir-frying; how to do that is in our guide to sautéing. Which pan is handiest for what is in our pan guide.
Blanching in short
Boil briefly, cool quickly in ice water, done. It is the best way to keep vegetables bright green, crisp and full of flavour, whether for the freezer or the plate. Keep the time short, and never skip the ice-water step.
