Unsealed jars

Asked September 17, 2020, 10:50 AM EDT

Jars boiled over...1" headspace, clean rims. Do I need to screw rims real tight? Is it possible to process too long? Tomato/veg sauce pints 50 min. I've had success in the past. Not new at this

Lackawanna County Pennsylvania

3 Responses

Are you pressure canning or hot water bath canning?
I will assume pressure canning.
There are a few reasons for unsealed jars, but do not tighten down the rings more than finger tight.
One issue is product getting into the seal area.
Before applying lid, make sure that the seal area is clean using a clean cloth.
Product can get onto the surface during the canning process.
Air bubbles in the jar at time of closure...make sure all air bubble are released through stirring.
Ensure you have the right amount of headspace. Minimal headspace also allows the product to more easily escape into the seal area.. Do not over pack product either.
Another issue is moisture loss from the jar, especially during cool down of the canner. Pressure release from the jars occurs as the jars essentially burp. This can be minimized by 1) letting cooling of the canner go as slow as possible, 2) not moving the canner at all until it is cool as well as the jar and 3) never depressurize the canner by removing the pressure release value, even when there is only one pound of pressure. Just leave the pressure release value. Along these same lines, wide pressure swings during processing can also cause product loss, so keep pressure as steady as possible.
Do not disturb lids once removed from the canner.
Are you preheating the lids? No real need to do that, and overdoing it can cause failure.
Bad lids / seal material...happens from time to time.
If you can provide additional informaiton based on this, perhaps we can narrow it down further.
For more information, visit the National Center for Home Food Preservation website. https://nchfp.uga.edu/

thank you. I'm wondering if lids are bad...rims were clean, headspace was bottom of lid threads, pressure was good, cool down was just turning off gas burner and letting the cool down happen on it's own. release valve removed after NO steam at all. some product had boiled over into the pot. 2 tomato soup consistency, and 4 pasta sauce (applesauce consistency). I processed pints 50 min 10-11 lbs because I feel this is basic. One of the soups did seal. weird... (PS...I have been pressure canning about 10 years)

I would file a complaint with the company who made your lids.