Maybe you’ve been walking down the freezer aisles, but can’t find the frozen broccoli you were looking for. Or maybe you’re wondering what to do with all those extra spinach you bought at the grocery store last week.
Freezing vegetables is a great way to keep them fresh and ready for future use yourself, which means meal preparation will take less time and effort once you get there. Plus, freezing can help reduce food waste because you’ll end up preserving the extra broccoli florets you bought instead of tossing them in the trash once they’re spoiled.
However, it’s not as simple as putting those extra vegetables in resealable bags and stacking them in the freezer; you will have to whiten them first.
What is whitening and why should I do it?
Whitening is a common cooking practice that uses water or steam for a short period of time. This process destroys the enzymes that cause the vegetables to deteriorate and helps the frozen vegetables to taste the best.
Bleaching also removes microorganisms or dirt from the surface, brightens the colors of vegetables, and helps slow nutrient loss . Blanching also shrinks or softens vegetables, making storage more compact.
How to blanch vegetables?
Although it is an additional step, blanching is relatively simple. There are three ways to blanch vegetables: by boiling them in water, steaming them, or microwave them, listed below.
Before blanching, be sure to wash your vegetables properly and thoroughly to remove any residue.
Before you start, make sure you have:
- A large pot or saucepan.
- Mesh basket.
- Freezer bags that can be resealed.
Water bleaching
Dipping vegetables in boiling water is quick, effective, and takes the least amount of time. However, water bleaching can cause water-soluble nutrients (including B vitamins and vitamin C) from vegetables to leak. To use this method:
- Bring 4 liters of unsalted water to a boil in a large pot.
- Place 230 grams of green leafy vegetables or half a kilo of other vegetables in a mesh basket. If you don’t have any of these things, you can add the vegetables directly to the boiling water.
- Cover with a tight fitting lid, keep the heat high and set the timer to the required cooking time (below is the guide).
- Drain and soak the vegetables in an ice water bath to stop the cooking process. Keep them in ice water for the same time they were cooked. Then spread them on kitchen paper and pat dry.
- Put blanched vegetables in airtight bags or containers and freeze immediately.
Steam bleaching
Steam blanching is the recommended method of blanching vegetables. Offers the freshest flavor and retains water soluble nutrients. Just be aware that steam bleaching takes longer than water bleaching. To use this method:
- Bring 40 cl of water to a boil in a large saucepan with a tight fitting lid.
- Arrange the vegetables in a single layer in a steam basket and place the basket on top of the water.
- Cover well, keeping heat high, and set the timer to the required cook time.
- Periodically during the cooking process, lift the lid and shake the basket to ensure even cooking at all times.
- Remove the basket and soak the vegetables in an ice water bath to stop the cooking process. Keep them in ice water for the same time they cooked. Then spread them on kitchen paper and pat dry.
- Store blanched vegetables in airtight bags or containers and freeze immediately.
Microwave bleaching
This method is not recommended for bleaching because some enzymes may still be present. This can create unpleasant textures, colors, flavors, and poor quality.
If you choose to blanch vegetables in the microwave, consult your microwave oven instructions.
|
Vegetable |
Preparation |
Time (in the water) |
Time (steam) |
Maximum frozen time |
| Asparagus | Cut the woody ends; cut into pieces or leave them whole | Pieces or small stems: 2 minutes.
Medium stems: 3 minutes Large stems: 4 minutes. |
Add 1 ½ minutes to each |
4 months |
| Peppers | Cut in half, remove stems and seeds, leave in halves or cut into julienne strips | Halves: 3 minutes
Strips: 2 minutes |
Add 1 minute to each |
6 months |
| Broccoli | Cut and cut into 2 cm pieces. | 3 minutes | 5 minutes |
6 months |
| Carrots | Peel; leaves small carrots whole or diced, sliced, or julienne / strips | Small integer: 5 minutes
Diced or julienned: 2 minutes |
Small integer: 8 minutes Diced or julienned: 3 minutes |
6 months |
| Cauliflower | Cut and cut into 2-centimeter pieces | 3 minutes | 5 minutes |
6 months |
| Corn | Cut the shell, remove the silks, trim the ends and rinse. Sort by: small ears of a centimeter or less in diameter; medium-sized pods half a centimeter in diameter; large ears, more than 1 cm. | Small: 7 minutes
Medium: 9 minutes Large: 11 minutes |
Small: 10 minutes
Medium: 13 minutes Large: 16 minutes |
6 months |
| Green leaves (Swiss chard, Swiss chard, kale, spinach) | Remove stems | Cabbages: 3 minutes
Others: 2 minutes |
Steam not recommended; instead, sauté over high heat until wilted |
4 months |
| Green beans | Remove the ends; cut into 4-centimeter pieces or leave whole | 3 minutes | 4 minutes |
4 months |
| pumpkin | Cut into 1 centimeter slices | 3 minutes | 4 minutes |
6 months |
| Tomatoes | Leave everything | 30 seconds to loosen skin, then peel, core and leave everything or cut into pieces before packing and freezing | Not recommended |
1 month |
