Blanching is a simple process that basically means to quickly cook an item in boiling water. If you are freezing fresh produce from your garden or the market, this is a simple step that you can take to help ensure that your frozen vegetables hold up well in the freezer and taste great when you use them in meals months later.
Why Blanching is Important
This process, which is necessary when freezing most vegetables for longer than one month, stops enzymatic damage that would otherwise destroy the flavor and texture of vegetables during storage. Additionally, it removes dirt and microorganisms and helps to retain vitamins during freezer storage.
Vegetables that should be blanched before freezing include broccoli, green beans, corn, okra, spinach and other leafy greens, Brussels sprouts, cauliflower, summer squash, and peas.
How To Blanch Vegetables for Freezing
Before you get started, wash, drain, sort, and cut vegetables into uniform sizes in preparation for blanching. You can typically do this while the water is coming to a boil, so be sure to set a pot of water on the stove to boil before you get started.
If you are blanching a large amount of vegetables, you will need to do it in batches so as not to overcrowd the pot. Because blanching relies on a very quick cooking, it is important that the water is able to resume a boil within 1 minute of adding vegetables to it.
Use 1 gallon of water per 1 pound of vegetables for blanching. Bring the water to a rolling boil over high. You will know that you have achieved a rolling boil when you cannot reduce the bubbles coming to the surface by stirring the water.
How-To Prepare an Ice Bath
Most vegetables are only blanched for 2 to 3 minutes and it is important to have the ice bath ready before beginning blanching to avoid overcooking your produce. Fill a large bowl or clean sink about halfway with ice and then fill it with cold water, leaving enough room to account for the amount of vegetables to be added.
If you are doing several batches of a vegetable, you will need to refresh your ice bath several times throughout the process so be sure to have extra ice on hand. A good rule of thumb is to leave vegetables in an ice bath for the same amount of time that they were blanched in boiling water, or until they are cool to the touch. Once the time is up, use a strainer or large slotted spoon to remove the vegetables from the ice bath.
Getting Started with Blanching
Use a steaming basket or metal strainer to lower the vegetables into the water and set a timer immediately based on what type of vegetable you are blanching.
Here are some basic times for different types of vegetables:
- Artichoke hearts: 6 minutes
- Asparagus: 3 to 5 minutes
- Broccoli: 2 minutes
- Brussels sprouts: 3 to 5 minutes
- Cauliflower: 3 minutes
- Corn cobs: 3 minutes
- Green beans: 3 minutes
- Leafy greens: 1 to 2 minutes
- Okra: 2 minutes
- Shelled peas: 1 to 2 minutes
- Summer squash: 3 minutes
Depending on the size of vegetables and how big or small you prepare them, the time may vary slightly. Vegetables should not be tender and fully cooked, but greens will be wilted.
Once the time is up, remove the vegetables and transfer them to the ice bath. Leave the vegetables in the ice bath for at least the same amount of time as they were blanched, or until they are completely cool.
Packing Vegetables for Freezing
Drain the vegetables in a colander before packing into freezer-safe bags or containers. Excess water at the time of processing can deteriorate the quality of your frozen foods, so be sure to allow vegetables to thoroughly drain.
Blanched vegetables can be packed in freezer-safe containers or bags, depending on your space and preference. Bags are particularly convenient, as you can freeze them flat and stack them easily in the freezer to save space.
When Not to Blanch Vegetables
While many vegetables benefit from blanching before freezing, vegetables that are used primarily for flavoring such as green onions, bell and sweet peppers, hot peppers and herbs do not need to be blanched before freezing. To freeze these vegetables, wash and prepare them as you wish and pack them into freezer-safe storage bags or containers.
Useful Tips For Freezing Vegetables
Here are a few tips to help ensure you have the best quality of frozen vegetables possible:
- Add up to a tablespoon of salt to the blanching water to add flavor to the vegetables. Be sure to label the item as ‘salted’ before freezing.
- When batch cooking items of various sizes such as Brussels sprouts, group the items by their size and adjust blanching time slightly to account for the variation.
- To remove air from freezer storage bags, seal the bag except for a small opening on one side. Insert a straw, suck out as much of the air as possible, remove the straw and quickly seal the bag.
