Can glass jars be used in freezer?

Glass jars can be used in the freezer, provided they are designed for such use and are properly prepared. Here are some guidelines for using glass jars in the freezer:

Choose jars specifically made for freezing. Look for jars that are labeled as "freezer safe" or "suitable for freezing."

Leave headspace. When filling jars with liquids, leave at least 1 inch (2.5 cm) of headspace at the top to allow for expansion during freezing.

Avoid sudden temperature changes. To prevent cracking, place jars in the refrigerator for several hours before putting them in the freezer. Similarly, when removing jars from the freezer, let them sit in the refrigerator for a while before bringing them to room temperature.

Never put hot food directly into the freezer. Allow hot food to cool completely before placing it in a glass jar and freezing.

Don't overfill the jars. Overfilling can put pressure on the glass and cause it to break.

Thaw jars slowly. To thaw glass jars, place them in the refrigerator or set them out at room temperature for several hours. Avoid thawing them in the microwave or with hot water, as this can cause the glass to crack.