Freezing Techniques

Frozen produce can be prepared in numerous ways. As you try your hand at the recipes on this site, you’ll frequently be referred back to this page for the best way to prepare a particular fruit or vegetable for long-term storage in the freezer.

Harvest to Bag

Many vegetables and fruits can be stored in your freezer with hardly any effort, including onions, peppers, peas, strawberries, apples, and cherry tomatoes. It’s easy to complete your harvesting and processing in one session, with minimal fuss.

  1. Harvest the produce you want to freeze slightly before its peak; these firmer foods are easier to handle and keep better in the freezer.
  2. Wash the produce and let it drain and dry before handling.
  3. If desired, peel, snap, slice, and/or chop the produce, depending on its whole size and your intended use.
  4. Pack the produce into labeled zip-close freezer bags, pressing as much air from the bag as possible before sealing.
  5. Place in a single layer in the coldest part of your freezer until the contents are completely frozen before shifting the bags.

Follow these same basic steps when applying any of the techniques below.

Tip onto a Tray

Have you ever pulled a bag of raspberries from the freezer only to find they’ve formed a solid red block? While that may be due to thawing and refreezing, it can also happen if you pack fresh raspberries into a zip-close freezer bag—they’re that delicate. Here’s the best solution.

  1. Gently spread the individual berries in a single layer on a rimmed tray or pan.
  2. Set the whole pan in the freezer for several hours or overnight, until the berries are completely frozen.
  3. Pop the frozen berries off the tray. Depending on your tray, you may be able to flex it, as you would an ice cube tray, or you may need to slide a food scraper or spatula under the berries to gently pry them loose.
  4. Place the berries immediately into a labeled zip-close freezer bag. Put the bag into the freezer straightaway to preserve your efforts, as well as your berries.

This technique works for almost any fruit or vegetable that tends to clump in your freezer: cherries, corn, or anything you’ve diced before freezing.

Grate the Giants

Some vegetables just don’t freeze well, because they hold too much water. But I can only eat so many pickled cucumbers and zucchini. The solution? Grate them, and then freeze the gratings, and perhaps even the juice. It’s also a fabulous way to deal with oversized or blemished produce.

  1. Cut off any damaged parts of the produce.
  2. Set a strainer between a flat grater and a bowl so that the juice starts to separate as you work.
  3. Grate, using the widest holes on your cheese grater.
  4. If desired, toss a teaspoon or so of salt in with the gratings to help draw out even more liquid.
  5. Let the gratings continue to drain until they no longer drip. If they still seem to hold too much liquid, grab a handful at a time and squeeze gently.
  6. Pack 1-cup and larger portions into labeled zip-close freezer bags or freezer-proof containers. For smaller portions or usable separated liquid, grab an ice cube tray.

Gratings don’t refreeze well, so plan to use the amount you defrost in one or more recipes. For example, freeze larger portions for Zucchini Pancakes and cubes for Tatziki. If you’re grating cucumbers, don’t throw out the juice: It can be frozen in cubes and used for midwinter Cucumber Mojitos.

Pop in a Cube

Rhubarb syrup cubesIce cube trays are great for freezing all sorts of things in small portions. It’s my preferred way to save pestos, liquids such as Rhubarb–Rosemary Syrup, curry pastes, and savory purees that I can toss into a dish for a bit of bright flavor on a rainy fall day.

  1. Pour or pack your item into the cups of the tray.
  2. Set the tray in the freezer for several hours or overnight, until the contents are completely frozen.
  3. Pop the cubes loose, flexing the tray to free them from the cups.
  4. Place the individual cubes straight into a labeled zip-close freezer bag and then the freezer.

When you need what you’ve saved, simply open the bag, pull out the number of cubes you need, and reseal the bag before returning it to the freezer.

To Blanch or Not To Blanch

There’s a bit of a debate in the preserving world about whether you need to blanch certain vegetables. Here’s the skinny: Blanching heats produce quickly and briefly before it is frozen. Both blanching and freezing help to break down the cells in vegetables and let the gases inside them escape. But where heat stops enzyme activity in vegetables, freezing temperatures do not. These enzymes don’t spoil food, but over time they do make it softer and duller.

So whether to blanch is not a food safety issue; it’s a quality issue. Which means the question of to blanch or not to blanch is really up to you. Most fruits (including tomatoes) don’t need to be blanched, nor do foods grilled or otherwise prepared in a way that already hinders enzymes. I do recommend blanching for broccoli.

If you do decide to blanch, I recommend following the steam-blanching process—and particularly the timing—provided by the National Center for Home Food Preservation for the specific vegetable. As the center notes, blanching for too long defeats the whole point of the process, and underblanching “is worse than no blanching.”