Thermal Shock Examples

Thermal shock can happen any time a rapid change in temperature occurs, whether you’re going from hot to cold or the other way around. Here are the most common ways thermal shock happens in the kitchen:

• Rinsing a hot pan in cold water

• Placing a cool pan directly on high heat (i.e., turning on a burner, getting it nice and hot, and then placing your pan on top of the heat source)

• Placing a cool baking sheet or pan in a hot oven

• Putting hot kitchenware on a cold surface, such as a countertop or fridge shelf

• Filling a cold glass with hot water

Thermal Shock and Cookware Materials

Regardless of what your kitchenware is made from, almost all materials have some (albeit differing) potential of being damaged due to thermal shock. Let’s take a look at some common kitchen materials and how they might react to extreme changes in temperature:

• Ceramics. Thermal shock resistance in ceramic cookware and dishes can vary greatly depending on the composition. That means some ceramic pieces with low tensile strength can be susceptible to cracking due to thermal shock, while others can be quite resilient.

• Glass. When it comes to thermal shock and glass, factors like thickness and tempering can make a difference. While untempered glass is prone to shattering due to thermal shock, other types of glass, like borosilicate glass (often used for food storage containers), are much stronger and resistant to thermal shock.

• Aluminum. Although aluminum is known for its heat conductivity, thermal shock can still be an issue for cookware like aluminum sheet pans. They won’t crack or shatter like glass/ceramics, but they are prone to warping.

• Stainless steel. The potential for stainless steel cookware to experience damage due to thermal shock is much smaller compared to the materials listed above. Cheaper stainless steel cookware still has some potential to deform, but so long as you’re using quality pots and pans, you don’t need to fuss over thermal shock with stainless steel. Still, it’s best to allow your pans to cool off before exposing them to cold water

• Cast iron. Cast iron is the go-to high-heat cookware, which is why, despite it being very durable, you should be careful exposing cast iron to cold temperatures too soon after using it. The extremely high temperatures cast iron can hold onto gives it more opportunity to experience thermal shock that could eventually result in warping or even cracking.

As a general rule, it’s good practice to always introduce gradual temperature changes to help aid the longevity of your cookware. This means generally avoiding placing items directly on high heat, and always allowing sufficient cooling time before placing them under cold water. Alternatively, you can use warm water for cookware that needs to be cleaned more urgently.

How to Prevent Thermal Shock in Cookware

If you spend enough time in the kitchen, odds are you’ll experience thermal shock to an item of cookware at some point in your life (accidents happen!). When it comes to keeping your kitchen thermal shock-free, here are some best practices:

• After the cooking is all done, give your hot pots and pans plenty of time to cool down before putting them in the sink. It’s also best to use room temperature or warm water once it’s time to get to cleaning.

• Allow your cookware to heat up gradually, rather than putting it directly onto high heat.

• If you plan on putting kitchenware in the freezer or fridge, make sure you’ve given it (and any food inside) sufficient time to cool down.

• Avoid putting items straight from the fridge or freezer in the oven or on the stove.

• Give your food some time to come to room temperature if it has been frozen or refrigerated before placing it in the pan. This will help avoid thermal shock to your cookware and keep your food from sticking or unevenly cooking.

One final and effective way to avoid thermal shock is to simply buy thermal shock-resistant cookware. While even the strongest materials can still succumb to thermal shock given extreme exposure, kitchenware with features like treated glass, vitrified ceramic, and high-gauge aluminum will help ensure no accidental damage is done.

Can You Fix Thermal Shock?

If you find yourself here after already experiencing thermal shock to your favorite piece of cookware and are wondering if you can fix it, the answer is that it depends. 

Generally, you can’t do much once cookware has experienced thermal shock. That’s because thermal shock does more than just change the shape of your cookware—it compromises the structural integrity of your pots and pans, which means they won’t heat food as evenly or effectively.

For items like sheet pans, there is a chance at salvation. Typically, a sheet pan that has been warped by thermal shock will settle back into place once it returns to room temperature. If you find it isn’t going back into shape, you could try: 

1. Heating the sheet in the oven at 200°F for 10 minutes

2. Taking it out and laying it upside down on a towel

3. Covering the pan with another towel and using something like a mallet to gently tap it back into its original shape.

It’s guaranteed to work, but if it’s a beloved cooking sheet, it doesn’t hurt to give it a go!

Avoid the Shock of Thermal Shock

With the right kitchen habits and good, quality cookware, thermal shock doesn’t need to be a major worry for most chefs. If you’re in need of new cookware that offers long-lasting performance for any recipe, look no further than Circulon!