water loss in pressure canning

[duckidaho]

We pressure canned some carrots and the jars lost about an inch of the water in them, leaving the top couple of carrots exposed. The seals are good. Are they still safe? Russ

[Shamrock1121]

We pressure canned some carrots and the jars lost about an inch of the water in them, leaving the top couple of carrots exposed. *The seals are good. *Are they still safe? *Russ

1. How did you cool the pressure canner?

"Do not force cool the canner. Forced cooling may result in food spoilage. Cooling the canner with cold running water or opening the vent port before the canner is fully depressurized are types of forced cooling. They will also cause loss of liquid from jars and seal failures. Forced cooling may also warp the canner lid."

"Allow pressure to drop to zero naturally; waiting 2 minutes before opening lid."

2. How was the food packed into the jars - raw pack or hot pack?

It's best to use the hot pack method, rather than the raw pack, because it helps remove air bubbles, which can cause loss of liquid.

3. You may have packed the food too tightly in the jars.

4. Did you run a plastic spatula through the jars contents to remove air bubbles before placing the lid on the jar?

"Slide a non-metallic spatula between food and jar; press back gently on food to release trapped air."

The trapped air can force the liquid out of the jars.

5. It could also mean your pressure canner wasn't operating correctly. If the pressure fluctuates during processing time, it can cause the loss of liquid. (In which case, the food may not have been properly processed and the contents may not be safe to consume. Even if a lid seals, that doesn't mean bacteria can't grow in the jars. Bacteria grows best in a low-oxygen environment.)

6. Did you have 2-3-inches of water simmering, or hot, in the canner?

If you hot pack foods, the water needs to be 180°F. Raw packed foods, the water needs to be 140°F.

7. Did you leave 1-inch of head-space in the jars?

Is it safe to eat? Depends on what caused the loss of liquid....

-Karen

[lsg]

My guess is that you may have lost water in the form of steam escaping from the rubber safety valve or your gasket. I had to replace both the rubber safety valve and the gasket for my old pressure canner. It worked fine after that.

[CanNerd]

Catastrophic purging of the contents of a jar has two possible causes: (1) the spring lid is on too tight (it should be "finger-tight" only; or (2) there was a sudden exposure to a lower temperature.

#1 is the most common. As temperature builds up the "headspace" air is purged out. If the lid is too tight pressure will build up inside until it is suddenly released and results in most of the liquid rushing out.

#2 often occurs when the lid is removed before a cool down period is allow, especially if there is a fan blowing or a draft in the kitchen around the canner.

[lsg]

That's what I get for not reading the intial post carefully. I agree that too high a temp. can cause loss of water from the jars.
Perhaps your jars were filled too full.
Letting your pressure canner vent steam for about 10 minutes before tightening the pressure valve will help also.

[Mad_Professor]

Additional question on depressurizing.

If using a canner with a "whistler" . After cooling to the point it no longer whistles, can you remove the whistler, just allow to depresurize until no more steam evolves, then remove top?

OR does it need to cool to the point of no pressure before removing whistler. Seems this would increase time heated AND under pressure and result in mushy canned goods

[CanNerd]

The canner needs to cool to the point of no pressure before the weight is removed. *Removing it early is called "forced decompression" and could result in food spoilage. These times are factored in to entire processing time and will not change the condition of the food.

Additionally you should wait 10 minutes after that before removing the lid.

[anna]

If you allow pressure to fluctuate during processing, it will pull liquid from the jars. I take pressure up to 13 and let it go back to 12 and try to hold it there. 11 is recommended pressure but I prefer to process at 12 so if I get a drop I don't have to start timing all over because I've stayed above the recommended temp. If I fail to pay attention and pressure fluctuates up and down it always pulls liquid from the jars.

[pcrowder]

I've found that when I had the most trouble with fluid loss from the jars was when I was in a hurry and filled them too full.