Blanching Kohlrabi
Blanching, then freezing, is one of the easiest ways to preserve a Minnesotan fall harvest for winter enjoyment. You likely already have everything you need in your kitchen to start this food preservation method.
Blanching involves briefly scalding produce in boiling water and then immediately plunging it into an ice bath to halt the cooking process. It stops the enzymatic process that causes vegetables to lose their flavor, texture, and nutrients. Boiling also helps to remove any residual dirt and bacteria.
Blanching time varies depending on the vegetable. Avoid overblanching or underblanching. You can find exact boiling times for most vegetables on university extension webpages, such as the U of MN: Preserving food at home: Blanching vegetables | UMN Extension
Tools needed:
- Tall strainer. Tongs also work as long as you can rapidly transfer the kohlrabi from the boiling water to the ice bath
- Large Pot
- Knife and cutting board
- Large bowl or container for ice bath
- Ice (around 2-3 ice trays)
- Ziploc bags
Prep the Kohlrabi and Tools
First, chop off the leaves from the stem, and then wash them in a bin of water. Remove yellow or damaged leaves. The leaves and bulbous stem will be blanched and stored separately because they cook for different lengths of time. Trim and discard the stems from the leaves, chop the leaves, and place them into a bowl. For the bulbous stem, chop off the top and bottom and peel or cut off the tough outer skin. Cut into cubes and place in a bowl.
Note: Depending on how much Kohlrabi you have, you’ll likely need to go through the blanching process for a few batches. The leaves cannot be packed together; they need enough space to boil evenly.
Prepare a large bowl with ice water. Have extra ice ready to add for each new batch.
The Blanching Process for Leaves
- Fill a large pot about ¾ of the way full with water and bring to a boil.
- Using a strainer, dip kohlrabi leaves into the boiling water. Use a wooden spoon to press down any floating leaves and stir. Set a timer for 2 minutes
- Once the two minutes are up, immediately transfer and submerge into an ice bath. Stir the leaves in the ice bath. Remove from the ice bath after 2 minutes, squeeze out water, and place on a kitchen towel. Pat dry and package into Ziploc bags.
- Add more ice to the ice bath as needed and repeat the blanching process until all the leaves are done.
The Blanching Process for the Bulbous Stem
- Fill a large pot about ¾ of the way full with water and bring to a boil (Or use the same one that you used for the leaves).
- Using a tall strainer, submerge kohlrabi leaves into the boiling water. Set a timer for 1 minute.
- Once the minute is up, immediately transfer and submerge into an ice bath. Stir the leaves in the ice bath. Remove from the ice bath after a minute. Pat dry with a kitchen towel. Package in a Ziploc bag and freeze.
- If necessary. Repeat the process and add more ice to the ice bath.
