When it comes to testing food storage containers, Cook's Illustrated magazine and Good Housekeeping cover all the bases. At Cooks Illustrated, editors ran dry storage, plastic and glass storage containers through a series of tests. For storing dry goods, editors tested containers for their ease of storing a 5-pound bag of sugar. They also tested the seal by placing a slice of bread in each container for a week. To gauge their resistance to leaks, plastic and glass containers were submerged in water, and they were filled with soup and then shaken. After being put through the microwave and the freezer, the containers were run through 50 dishwasher cycles before going through the tests again.
Editors at Good Housekeeping had a similar evaluation of 28 food storage containers. They tested the containers for moisture seals by placing them in a humidity chamber and conducted durability tests by freezing liquid in the container and dropping it from counter level. Along with standard containers, Good Housekeeping tested common value options like disposable Ziploc and Glad containers.
ConsumerReports.org judges three food storage containers for stain resistance in a 2007 report. Testers filled food storage containers with pasta sauce and let them stand overnight before microwaving and washing them. In another set of tests, testers fill storage containers with cold cuts, cheese and produce, then place them in the refrigerator or on a counter for a week. Although these are tough tests, there's no evidence that the magazine tested containers for leak resistance -- an important consideration, given that many people transport food in their bags. Another source, Real Simple magazine, selects the top food storage containers in various categories (best for cookies, snacks and freezing meat) but reveals little about the methodology. Similarly, review site Bestcovery.com gives their expert's top picks in food storage with little explanation of their evaluation process.
We compared professional test results with owner opinions about food storage containers at Viewpoints.com, Amazon.com, QVC.com and Buzzilions.com. Although owner opinions are helpful for determining whether food storage containers crack, chip or discolor over time, reviewers often focus on brand name rather than specific containers, and it can be difficult to tell which containers are under review. The best owner reviews mention pros as well as cons and compare plastic containers to each other as well as to glass versions.
Given the concerns about bisphenol A (BPA) in some types of plastic, we were surprised to find so few professional reviews of glass storage containers, which don't contain BPA (though their plastic lids might). In testing, BPA has been linked with health risks in animals, and its effect on humans is either benign or dangerous, depending on whom you ask. As a result, most manufacturers are finding ways to eliminate BPA from their plastics. Look for the label "BPA free" on packaging. If you're not sure, note that plastics with a No. 7 recycling code are most suspect.
Polyvinyl chloride (PVC), a chemical used in soft, vinyl plastics, has also come into question. Like BPA, large doses of this chemical have been linked to health risks in animal testing. According to the Food and Drug Administration, PVC is not generally used in plastic food storage containers. Materials containing PVC are marked with a No. 3 recycling code.