Keeps glass warm

Heat-resistant glasses - all the facts

Melting point of glass

In principle, glass only melts at 600 degrees. Even so, normal drinking glasses will shatter when you pour boiling water. Unfortunately, glass is a poor conductor of heat and therefore cannot withstand sudden changes in temperature.

Glass thickness

The thickness of the glass is not always an indication of the heat resistance of the glass. A normal bowl or a simple drinking glass can withstand temperatures of up to around 50 degrees very well. Other temperatures apply to crystal or lead crystal glasses. They become dull and milky on the inside at high temperatures. You should not heat these glasses over 30 degrees permanently - not even when washing the dishes.

Check marking - buy heat-resistant glass

For hot drinks as well as for the casserole that you want to heat in the oven or microwave, you should buy special heat-resistant glass. The so-called Jena glass bowls, for example, have a marking on the underside that shows whether this bowl can only be used in the microwave or also in the oven. Another marking says that the bowl can even be used on the stove top. This is not the case with every heat-resistant bowl.

Warm up and freeze

Everyone knows that we have to let a bowl cool down before the food can be frozen. But even when defrosting it is important to slowly adjust the glass and the food to the changed temperature. It is ideal if you let the food thaw slowly in the refrigerator overnight.

Thaw and warm up frozen food in glass bowls

  • no hot water over frozen glass bowls
  • do not place on the hot stove
  • do not put in the oven or microwave
  • turn on at least the lowest setting in the microwave
  • If possible, let them thaw in the refrigerator
You should not put heat-resistant glasses in the preheated oven either. You should also only heat up the stove slowly when the glass vessel is already on it.