re: Reasons why jars break during canning

Hi,

Sorry to hear about the loss. Below is a list of reasons why jars break. Hope this information helps you out.

Reasons Why Jars Break
A. Thermal Shock is characterized by a crack running around the base or lower part of the jar and sometimes extending up the side.

1. Setting hot jars to cool on a cold surface or near a cold draft.

2. Accidentally spattering hot jars with cold water.

3. Not using a rack in the boiling water bath or pressure canner.

4. Filling jars of food with water or syrup that is not boiling.

5. Filling jars with cold food and plunging into boiling water.

B. Pressure Breakage is characterized by the origin of the break on the side. It is in the form of a vertical crack, which divides and forks into two fissures.

1. Using the oven to process home canned foods.

2. Using too high a headspace; therefore, not leaving enough space to permit tile expansion of the contents during heating or pressuring.

3. Not keeping the heat steady under the pressure canner.

4. Touching the petcock before all pressure has released from the canner.

5. Pouring cold water over the canner and not allowing the canner to cool down naturally.

C. Impact Breakage oThe origin of the break is at the point of impact and fissures radiate from the point of contact.

1. Using jars that have received trauma from rough handling in transportation or home use. The conditions such as dropping, hitting or bumping can cause breakage.

2. Using a sharp metal knife to remove air bubbles.

D. Other:

1. Using packers jars instead of canning jars.

2. If there is an imperfection in your jar, it will break the first time it is used. Test empty jars by immersing in water, bring to a boil and boil 15 minutes.

3. Using old jars. Jars have a life expectancy of 13 years. Kerr does not re-place jars that are more than 5 years old.