From Mongolia, about Freezing Ziploc Containers
"I recently read an article about plastic container. I use Ziploc. I don't warm it in microwave; however, I freeze my food inside Ziploc Brand twist and lock 4 cup containers. The article mentions about the code inside the triangle. I found mine have # 5 and the letter PP underneath. The article recommends 1, 2, 4 and 5. I feel OK with my Ziploc containers. However, I worry about one paragraph of the article regarding freezer: Do not freeze. Only put plastics in the freezer if they have a freezer-safe label. Freezer temperatures can cause plastics to deteriorate, which increases the leaching of chemicals into the food when you take containers out of the freezer to thaw or reheat. In my case, I have the word 'microwave safe' and nothing to state 'freezer safe'. Can I use my Ziploc containers or I have to search for some containers with 'Freezer-safe' label? Please advice, Respectfully yours. – Mongolia from Austin, Texas"
Hi, Mongolia! We’re glad you asked this question because we know there are a lot of misconceptions out there. We’re happy to tell you that Ziploc® Brand Containers CAN be used in the freezer AND in the microwave when they are used as directed on the package.
Ziploc® Brand products meet the safety requirements of the U.S. Food and Drug Administration (FDA) for temperatures associated with defrosting and reheating food in microwave ovens, as well as room, refrigerator, and freezer temperatures. These containers are okay to freeze and are designed to be used as such.
Here are some tips that might help when you are freezing food in your containers:
To freeze: Fill the container to within 1/4" to 1/2" from the top to allow for freezer expansion, then snap on the lid to seal. Too much air space in the container can cause ice crystals to form. If there is going to be a significant amount of empty space in the container, wrap solid food items with Saran™ Brand Plastic Wrap, then place them in the container. Store securely.
Please note: the container becomes slightly brittle at 30°F - 40°F (or below) and may crack if dropped, so handle it with care when removing it from the freezer.
If you have other questions about Ziploc® Brand products, feel free to give us a call at 1-800-558-5252!