Paige Weisskirch, UC Master Food Preserver Online Program Volunteer
Freezing fruit at home is one of the simplest and most effective ways to preserve your harvest, or that great farmers-market haul, so nothing goes to waste. It gives you the convenience of having high-quality, ready-to-use fruit at your fingertips, whether you're making smoothies, baking, or just grabbing a handful for a snack. Thanks to the innovations of Clarence Birdseye, freezing fruit has become an accessible and reliable way for home preservers to lock in flavor, nutrition, and value year-round.
Clarence Birdseye and the Invention of Quick Freezing
In the early 1900s, Clarence Birdseye was working in the frigid region of Labrador, Canada, where he saw Indigenous Inuit communities preserving freshly caught fish by exposing it to the bitterly cold Arctic air (sometimes as cold as -45°F). This method froze the fish almost instantly, locking in its flavor and texture. When thawed, the fish remained fresh and appetizing, unlike the mushy, watery results commonly achieved with the freezing methods commercially used at the time.
Birdseye realized that the key difference was speed. Fast freezing formed smaller ice crystals that didn’t rupture food cells. Driven by this insight, he returned to the U.S. and began designing mechanical freezing equipment. In 1924, he patented a process that used two refrigerated metal plates to freeze packaged food rapidly. By 1929, Birdseye had sold his patents to what would become General Foods, launching the Birds Eye brand and igniting the commercial frozen food industry.
Frozen Food in the American Home
Birdseye’s innovations made frozen food available in grocery stores by the early 1930s, but it wasn’t until after World War II that American homes began to catch up. Although early adopters purchased standalone chest or upright freezers, the more transformative innovation for everyday households was the development of the combination refrigerator/freezer appliance.
These combination appliances began appearing in U.S. kitchens in the late 1940s and early 1950s, integrating cold food storage and freezing in a single device. By the mid-1950s, more than 80% of American homes had a refrigerator, and a growing percentage included freezers. The convenience of having a freezer section built into the same appliance as the refrigerator made it easier than ever to store frozen vegetables, meats, and yes, berries.
As frozen foods became a staple of American life, so too did home freezing. With Birdseye’s quick-freezing principles built into the very design of modern appliances, freezing fresh fruit became both accessible and practical.
Freezing Berries the Smart Way: Start with Tray Freezing
Berries are a perfect candidate for freezing, but due to their high water content, they need to be frozen correctly to prevent them from turning mushy. The most versatile method is tray freezing, which keeps berries separate and allows for easy portioning later.
Follow these simple steps:
- Select fully ripe, firm berries. Remove leaves, stems, and any bruised or underripe fruit.
- Wash gently in cold water and drain thoroughly. (Tip: Use a salad spinner lined with paper towels – be gentle.)
- Allow the berries to dry thoroughly for an hour on the counter or uncovered in the refrigerator for several hours. (The less surface moisture, the better)
- Spread the berries in a single layer on a rimmed baking sheet and place in your freezer (in the coldest spot, ideally near the back).
- Once frozen solid (usually several hours), quickly transfer the berries into freezer-safe containers or bags. Squeeze out excess air before sealing or use a vacuum sealer.
Learn More About Freezing Options
If you plan to use your berries in desserts or cooked recipes, you may want to consider other methods, such as a syrup or sugar pack. You can learn more about these methods in the UC Master Food Preservers Guide: UC MFP: Fruit, Serve It, Preserve It.
Storage Tips for Success
- Keep your freezer at 0°F (-18°C) or lower.
- Use moisture- and vapor-resistant freezer containers or bags.
- Label foods clearly with the date frozen and contents.
- For best quality, use frozen berries within 8–12 months.
Thawing Tips
Thaw berries in the refrigerator for a slow, safe defrost. If you’re using them in baked goods or smoothies, you might not need to thaw them at all. For immediate use, berries can be thawed under cold running water or in the microwave if they’ll be cooked right away.
A Frozen Legacy
Clarence Birdseye’s innovation brought the convenience of frozen foods to every household. Today, every home cook benefits from his work. Freezing berries with modern home appliances and reliable techniques not only reduce food waste but also allows you to enjoy the taste of summer any time of year.