Frozen Food Trays Put in Garbage Frozen food trays can be recycled only if they are made of plastic #1 or plastic #2. Otherwise they go in the garbage. Ways to Reduce Create Your Own Frozen Dinners Frozen dinners can be more expensive than preparing that same meal by hand. To save on money and time, consider making dinners in bulk at the beginning of the week, which helps reduce how much waste that’s generated from frozen dinners. See these helpful tips. Did You Know? Frozen Food Trays: Now More Eco-Friendly Recycled plastic can now be used to make frozen food trays. ConAgra Foods and Associated Packaging Technologies partnered to use a new technology that cleans recycled plastic. Before this technology was available, regulations limited companies like ConAgra to only using new plastic for food trays.