There are many reasons why people choose to add this technique into their kitchen routine – from wanting to prepare fresh vegetables for freezing, or when they just want to lock in as many nutrients and enjoy them that day.
What exactly is blanching?
Blanching is placing vegetables in boiling water or steam for a short time (usually between 1 to 7 minutes depending on what vegetables you’re using and the size they’re cut), followed by quickly placing them in ice water before draining thoroughly.
Why do we blanch vegetables?
To get scientific for a minute, blanching inactivates the enzymes, which would otherwise cause loss of flavor, color, and texture that happens when you cook vegetables for too long or when you freeze them without blanching them first. It also brightens color and helps retain vitamins, while softening some vegetables like broccoli, asparagus, pumpkin, and sweet potato, making them easier to cook.
When you blanch bitter greens, like kale, you will find that in doing so, you remove that bitterness, while keeping their flavor fresh.
We also blanch tomatoes and peaches to make it easier to peel their skin – if making a tomato sauce for pasta night or stewing some peaches for dessert. Removing the skin of these two particularly soft companions can otherwise prove quite tricky.
Boiling water or steam blanch? Which is best?
Both methods of blanching achieve the same result, though some vegetables are better steamed (broccoli, sweet potatoes, pumpkin, and winter squash), while others boiled (carrots, peas, asparagus, corn, green beans, and cauliflower).
The main thing to know when steam blanching is that it takes about one and a half times longer in the steam than if you boiled it.
With the technique of both methods being similar, below is the list of things you will need:
- A blanching basket or any type of metal woven basket (alternatively, if you’re boiling and don’t have one, you would put your vegetables loose in the water and take them out using a slotted spoon)
- A large pot
- A lid
- An ice bath (a large bowl of ice water)
- Fresh vegetables
To prepare your vegetables for blanching, either leave them whole or chop them into your preferred size – keeping in mind this will change the overall time they will need to be blanched for.
How to boiling water blanch vegetables:
- Bring a large pot of water to the boil with a generous pinch of salt (roughly one gallon of water per pound of veg)
- Place the vegetables in the boiling water
- Cover the basket (if using) with a lid and begin counting the time from when the water returns to boiling
- Keep the heat high for the entire duration the vegetables are meant to blanch for
- Remove the veg and immediately plunge them into your prepared ice bath
- Cool the vegetables for the same amount of time as you blanched them for
- Drain them thoroughly after cooling
Ideally, you would place all of the same vegetable in your blanching basket at once. If you have a larger basket or a small number of vegetables, cutting them into appropriate sizes would ensure you can blanch them together, for example: chopping vegetables that need longer blanching time, smaller, whilst keeping the more delicate ones whole or chopping them as big as you possibly could.
Note: The water should return to boiling within one minute of adding the vegetables. If it does not it means that too many vegetables are being used for the amount of water.
How to Steam blanch
- Place three inches of water in the bottom of the pot and bring to a vigorous boil
- Add the steamer basket containing your prepared vegetables and cover the pot tightly with the lid. Make sure not to overcrowd your basket when you’re steaming (ideally not more than one single layer of vegetables is best to ensure all the vegetables get blanched evenly)
- Start counting steaming time as soon as the lid is on
- As soon as the veg has been steamed for the recommended time, immediately remove it from the heat and place it into the ice bath for the same time that you steamed them for, before draining them thoroughly.
Make sure to use a pot that comfortably fits your basket with a tight lid and a basket that holds the food at least three inches above the bottom of the pot (the wider the pot and basket are, the better).
It’s important to not over-blanch your vegetables, as you would be partially cooking them, which causes the very thing we want to avoid, like loss of flavor, color, vitamins, and minerals.
Blanching Times for Boiling (double if steaming)
- Broccoli (florets): 2 – 3 min (it should be bright green and just barely tender)
- Carrots (cut into sticks): 3 – 5 min
- Sugar snap peas: 3 min
- Asparagus: 2 – 4 min (depending on the thickness of the stems)
- Corn on the cob: 7-9 min (medium to large)
- Green beans: 3 – 5 min
- Brussel Sprouts: 3 min
- Cabbage (chunks) : 1 1/2 min
- Sweet potato (chunks): 3 – 5 min
- Spinach leaves: 2 min
- Cauliflower (florets): 3 min
- Zucchini (chunks): min
- Summer squash and pumpkin (chunks): 3 min
Why do we use an ice bath to blanch vegetables?
We follow up the blanching process by placing them in a bowl of ice and water in order to cool them rapidly, therefore it’ll stop the cooking process.
If we didn’t, the residual heat of simply leaving the vegetables to cool in a bowl would further cook them, completely undoing all of the benefits of blanching them.
Blanching tomatoes and peaches:
- Remove the core from the top of the tomato
- Make an “x” cut in the bottom of the fruit, keeping the cuts shallow
- Place them into boiling water for about 30 seconds for tomatoes, 40 for peaches
- Remove the tomatoes with a spoon and drop them into the previously prepared ice bath.
- After they’ve cooled in the ice bath (about 1 minute), take them out and peel. The skins should peel off easily, starting from the “x” you scored.
And voilà, simple steps to keep our vegetables nutritious and flavorsome as ever – whether to enjoy that evening, store in the freezer or preserve for another day.
How do you blanch fresh vegetables?
Start by preparing a large pot of water, bring it to a boil, add your veggies – once they’ve blanched for the recommended time, remove them from the pot and place into ice water, then drain them thoroughly.
How long do you blanch vegetables?
Different vegetables require different times, though it’s usually somewhere between 1 – 7 minutes, depending on the size and texture of the veg.
What vegetables are good for blanching?
Most of them! Carrots, peas, brussel sprouts, pumpkin and squash, string beans, sweet potatoes, sugar snap peas, fennel, cauliflower, broccoli – just to name a few.
Do you salt the water when you blanch vegetables?
Yes, add some salt to your water to help maintain the color of your vegetables and improve its flavor.
How do you know what is the right blanching time?
You can determine the right blanching time when the color has brightened and the vegetable looks fresh, and when it’s not too soft. Otherwise, it’s an indication that you might have begun cooking it.