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The Perils of Pyrex

Is Pyrex glassware susceptible to shattering?

Shattering is relatively rare, but it can happen when glassware is exposed to sudden temperature changes (known as thermal shock), extremely high heat (over 425 degrees), or direct heat. In fact, in the past decade, we have experienced three such incidents in the test kitchen.

Precautions you can take to avoid shattering include fully preheating the oven before placing glassware inside (to avoid exposure to the very high temperatures that some ovens initially use to jump-start preheating); covering the bottom of the dish with a little liquid prior to cooking foods that may release juices (to keep the temperature of the dish even); placing hot glassware on a dry cloth (to avoid contact with a cool or wet surface); never placing glassware on a burner or under the broiler; never adding liquid to hot glassware; and never moving a glass dish directly from the freezer to the oven or vice versa. Both of the leading glassware brands in this country, Anchor Hocking and World Kitchen (the U.S. manufacturer of Pyrex) offer more detailed instructions on all packaging and on their websites.

Clear glass cookware has many advantages: It’s inexpensive, provides even browning, and makes it easy to monitor progress. But if you want to avoid glassware altogether when baking, we recommend Rose’s Perfect Pie Plate by Rose Levy Beranbaum ($19.99) and the HIC 13 by 9-inch Porcelain Lasagna Baking Dish ($37.49). Both are ceramic and broiler-safe.

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