Canning question

[JohnnyP]

Have a quick canning question, figured this would be the place since there is lots of tune'r canners here.

When a recipe calls for canning say at 11lbs for 100 minutes and one accidentally let the pressure drop to 10 or 9 lbs the instructions are to start the time over at zero once the pressure is back up to 11 lbs. Why is that? Why does it have to start over at zero time. What if one had 5 minutes left to go on the time (cooked at 11lbs for 95 minutes), start all over? I'm trying to figure why this is and what would happen if you didn't start over? Anyone know? Thanks.

[danger]

Originally Posted by JohnnyP

Have a quick canning question, figured this would be the place since there is lots of tune'r canners here.

When a recipe calls for canning say at 11lbs for 100 minutes and one accidentally let the pressure drop to 10 or 9 lbs the instructions are to start the time over at zero once the pressure is back up to 11 lbs. Why is that? Why does it have to start over at zero time. What if one had 5 minutes left to go on the time (cooked at 11lbs for 95 minutes), start all over? I'm trying to figure why this is and what would happen if you didn't start over? Anyone know? Thanks.

Sorry, I don't buy the "if the pressure drops to 9 lbs, start the clock over". Maybe add an additional 10 minutes if it makes you worried, but what are we talking, 5 degrees difference. As if your gauge is that accurate anyway.

[iwanttofish]

It happens, it should not kill you, it has not for me. But if you are worried I can dispose of it for you

[namu mac]

Higher pressure = higher temp. It takes a certain temp to kill the potential botulisim. That said, when my pressure drops below 11# I quickly boost the heat and get the temp up PDQ. Dont; know about others,but I baby sit the cookers all thru the 100 min. Boring but the results are worth the wait.

[StickFish]

That is why I use 12-13# so and I can react to a small pressure change.

[CR dog]

My cooker regulates at 14psi.

[fishin' is livin']

By the book they say that when pressure drops below target, to stop time until back up and then resume. I don't sweat a pound or two for a short period. The cooking times have a good size buffer built in, but don't think that cutting short is a good idea.

[Chass]

WOW, I've never had this problem. I can indoors on my stovetop (the smell is gone in a day) so I get things rolling at 15 psi where my Presto canner maxes out at and then turn it down to medium. The pressure stays nice and even at 15 the whole time.

That said, I had a batch drop once for a different set of reasons. So I started the process over with another canner after it cooled. The tuna didn't look right inside the jars. It was dark and very dry when I ate it. Edible but different than the typical 100 minute stuff.

Chass
ct

[JohnnyP]

I've spent a lot of time researching this and found on one of the Gov websites (looked at lots but possibly nchfp) and it specifically says that if pressure drops below recommended poundage to start the time over....not just add minutes after reaching desired poundage again.
I have my gauge checked every year and I'm one pound off so I run at 12-13 pounds if 11 lbs is what is required. What I'm trying to figure out is how Botulinum spores are killed.
It's not worth sickening myself or family due to ignorance and I'm just trying to figure this out and I haven't been able to find detailed information.

[Pelagic Captain]

safety always .. this is not just pressure/temperature but also time...it is important to maintain pressure for the time interval to assure the kill

[fishbait]

If you consider that 10 lbs is 140 deg and 15 lbs is 150 deg and then take into consideration the themal mass of the tuna, jars and the canner, then IMHO having the pressure drop a few pounds for a few minutes is not a big deal at all. I would bet you could drop the pressure by 4-5 lbs half way intot he cooking process for 5 min and the internal temp of the tuna inside the jars would not be impacted at all.

I have had it happen many times and never been an issue.

[One Eyed Jack]

If iwantofish gets to much. I`ll take the extra. I`m also old school and wich to dye at 90 or 95 So th little thing aren`t that inportant to me.

[1991 Arima]

Agree with namu mac, just babysit canner, very boring but well worth it in the longrun.!!!

[Pilar]

Originally Posted by fishbait

If you consider that 10 lbs is 140 deg and 15 lbs is 150 deg and then take into consideration the themal mass of the tuna, jars and the canner, then IMHO having the pressure drop a few pounds for a few minutes is not a big deal at all. I would bet you could drop the pressure by 4-5 lbs half way intot he cooking process for 5 min and the internal temp of the tuna inside the jars would not be impacted at all.

I have had it happen many times and never been an issue.

Steve check your steam property tables. JK Water temp and pressure are locked together so to speak. If you know the pressure you also know the temp.

10 psig is about 240 deg
15 psig is about 250 deg

The issue is botulinum spores which can grow in a sealed jar in a low acid environment. USDA decided at some point to specify a temperature and time to certify destruction of botulinum spores in canned food. Thats where the time at a certain pressure comes from. 250 degrees (15#) for 100 minutes is the blue book recommendation.

If you for instance flame out due to no propane left and you notice a little later because there is no hopping weight sound. The pressure will drop pretty slowly. Then just change out the bottle and restart the time when the pressure is above the number. Mine will only run at like 17# so I go for 100 minutes and call it good. I check every 10 minutes or so. And you can hear the pressure controller on the canner, it's noisy.

[Tinman]

Many pressure gages read low. For example, when mine reads 10 pounds, the real pressure is 12 pounds. Go get your gage tested (try hardware stores). If your gage reads low, you might never have actually gone below 11 pounds. It's worth checking into.

[MegaByte]

I have had to babysit my canner as well. I use 10 pounds for 110 minutes. Often the thing goes over and I reduce the heat and then it may go down to 9 or even 8. When that happens, I crank the heat up and try to find the magic point where the thing stays relatively stable. I agree with the other post that says just add a few minutes. I have been eating my own canned salmon and tuna for over 30 years and I am still alive and have never got sick. I know that when the timer goes off, the jars are in a full boil and I can' imagine any bacteria that could survive that for over 100 minutes. Canning should be done at your own risk! Bottom line, if they don't seal and pop, don't eat it. I would not even re-can the stuff. Feed it to the neighbors cat!

[Walknbob]

Originally Posted by MegaByte

I use 10 pounds for 110 minutes. Often the thing goes over and I reduce the heat and then it may go down to 9 or even 8. When that happens, I crank the heat up and try to find the magic point where the thing stays relatively stable.
Bottom line, if they don't seal and pop, don't eat it. I would not even re-can the stuff. Feed it to the neighbors cat!

Yeah we have canned salmon for many years and a slight fluctuation is not unusual. If a jar doesn't seal properly (which is not necessarliy related to a minor temp fluctuation) then stick it in the fridge and eat it soon. We've never had any problem.

One thing I have found is that if the pressure goes too high and you try to dump pressure too fast it can suck juices out of the jars and you can end up with a "dry" product. That happened one of the first times we canned/jarred salmon.

[fishbait]

Man, tough to get old.

10 lbs is 240 NOT 140............ Jeepers,

thanks for the correction John

[ron m]

Originally Posted by Tinman

Many pressure gages read low. For example, when mine reads 10 pounds, the real pressure is 12 pounds. Go get your gage tested (try hardware stores). If your gage reads low, you might never have actually gone below 11 pounds. It's worth checking into.

Be carefull about assumptions. The guage on one of my canners reads two pounds low, not high. Best to have it checked, then you'll know, at least for a while.
ron m

[fishin"G"man]

I have an old presto with the rocker top. I did my tuna and salmon for 100 min and it came out good. I never had an issue nor have the other family members who seem to believe the NW salmon I send them is to die for.

No deaths just yet!

[Okie]

There seems to be much confussion on the canning process. On fish that has been smoked and cooked in this manner and is eatable before it is canned, the canning process time can be much less. To obtain a sealed jar is all that is neccessary to prevent botulissim. And the quality of the fish will be much better than if it is canned per goverment recomentdations, ( Which is for raw fish, that has never been cooked. )

No way will this cause you any trouble if a proper seal on the jar is obtained. I do no some people seem to ignore good advice when they hear it. The end results is in the quality of the fish being canned. This is for fish that has been smoked and cooked all ready to eat. The canning process can be much less than the convential wisdom and goverment rules show.

[WillFish]

Originally Posted by Okie

There seems to be much confussion on the canning process. On fish that has been smoked and cooked in this manner and is eatable before it is canned, the canning process time can be much less. To obtain a sealed jar is all that is neccessary to prevent botulissim. And the quality of the fish will be much better than if it is canned per goverment recomentdations, ( Which is for raw fish, that has never been cooked. )

No way will this cause you any trouble if a proper seal on the jar is obtained. I do no some people seem to ignore good advice when they hear it. The end results is in the quality of the fish being canned. This is for fish that has been smoked and cooked all ready to eat. The canning process can be much less than the convential wisdom and goverment rules show.

This is definitly NOT true-
"To obtain a sealed jar is all that is neccessary to prevent botulissim."

It is very easy to seal a jar of food by just heating it in boiling water. Botulinum spores can survive 212º F temperatures and must be heated at a higher (240º F) for a period of time (100 minutes) to kill. This is why non-acid foods such as fish and green beans need to be pressure canned to safely store at room temperature.

[sss5358]

Originally Posted by WillFish

This is definitly NOT true-
"To obtain a sealed jar is all that is neccessary to prevent botulissim."

It is very easy to seal a jar of food by just heating it in boiling water. Botulinum spores can survive 212º F temperatures and must be heated at a higher (240º F) for a period of time (100 minutes) to kill. This is why non-acid foods such as fish and green beans need to be pressure canned to safely store at room temperature.

Absouletly true. I agree with Willfish. Just because food is cooked (and especially low or non-acidic foods) doesn't mean botulinum spores won't form during the low temperature process. You may want to read this article on canning pre cooked fish http://extension.oregonstate.edu/cat...pnw/pnw194.pdf

from Oregon State. Just scroll down about mid way and it will address pre cooked tuna. But the species makes no difference.

Steve

[fishin"G"man]

I've done the 20 minute "seal the jar" in the pressure cooker with smoked fish. The fish has been cooked/smoked prior to putting it up. Most of the time the fish are put up in vacuum seal bags and frozen until thawed for use.

Getting back to the pressure cooker method... I see that the Extension Unit says to cook for 100 minutes no matter what. IMO that really dries out the smoked fish and overcooks it. Having sealed smoked fish in cans sealed with 20 minutes in the pressure cooker I have not had any problems. Nor have I had any problems with smoked fish put up in vacuum seal bags. That's where I have to ask the logical question... What's different?

Maybe someone can explain the difference of "accepted canning methods". The vacuum sealed bags are not even cooked twice and there is not one instance of problem after 5 years of doing this. Stores all over the country sell smoked fish in vacuum sealed bags.

Two years ago I chose the "quick seal" method- sealin the jars with 20 min in the pressure cooker. I adjusted the smoke time so it wasn't drying out the fish. Then, when put into jars they are finished in the cooker. The oils are boiling inside the jar and the jars are well sealed with no problems.

Just don't see the difference. Cooked is cooked- smoked is smoked. Both are accepted methods of preservation.

[Okie]

Originally Posted by fishin"G"man

I've done the 20 minute "seal the jar" in the pressure cooker with smoked fish. The fish has been cooked/smoked prior to putting it up. Most of the time the fish are put up in vacuum seal bags and frozen until thawed for use.

Getting back to the pressure cooker method... I see that the Extension Unit says to cook for 100 minutes no matter what. IMO that really dries out the smoked fish and overcooks it. Having sealed smoked fish in cans sealed with 20 minutes in the pressure cooker I have not had any problems. Nor have I had any problems with smoked fish put up in vacuum seal bags. That's where I have to ask the logical question... What's different?

Maybe someone can explain the difference of "accepted canning methods". The vacuum sealed bags are not even cooked twice and there is not one instance of problem after 5 years of doing this. Stores all over the country sell smoked fish in vacuum sealed bags.

Two years ago I chose the "quick seal" method- sealin the jars with 20 min in the pressure cooker. I adjusted the smoke time so it wasn't drying out the fish. Then, when put into jars they are finished in the cooker. The oils are boiling inside the jar and the jars are well sealed with no problems.

Just don't see the difference. Cooked is cooked- smoked is smoked. Both are accepted methods of preservation.

You got it right, old man, But it's hard to convince some people that the goverment rules are not exactly applaid for fish that has all ready been cooked.

Your comments are very much correct.

Good Luck

[STGRule]

The difference is easy. Vac-packing and freezing preserves by protecting from ice crystals (freezer burn) and slowing down the rotting process by keeping molds at bay with low temps. The lower the temp in the freezer, the longer your product is edible.

Canning kills the anaerobic bacteria that can grow in a vacuum (canning makes a vacuum in the jar). Heat is the only thing that kills anaerobic bacteria. And oxygen keeps it from growing. Remove the oxygen and you have the perfect petri dish for it to grow if you don't kill it with heat.

Brining and smoking removes most of the moisture from the product so 100 minutes will ruin it. You just have to run it for a short time with a lot of smoke and then can it.

[fishin"G"man]

STG rule... I hear what you are saying but that doesn't answer my question. Consider all the vacuum sealed fish for sale in the store. I see it at Costco, Fred Meyers, Safeway etc every where. The fish is vacuum sealed and as far as I know never saw a freezer much less a canner for 100 minutes to kill botulism. Hard for me to believe the FDA would allow vacuum packing if all that method did was delay botulism from growing.

So here's how I see the governments reasoning; The fish in the vacuum sealed bag is a botulism petri dish and all that separates it from ruin is oxygen. The 100 minute canning process seals air but there won't be any botulism because you've cooked it to death... So as soon as oxygen gets to the vacuum sealed processed fish the product begins it's botulism process and you die soon after. HUH?????????? I don't think so!

So the question remains... how can these people sell the botulism infested product with permission of the FDA or other food contamination group? The answer is they can't, wouldn't and couldn't. Therefore, the fish smoked and vacuum packed preservation method is not death in a vacuum sealed package. It is preserved just as any legitimate canning process would.

I don't fear government... I fear the people running/abusing it.

[OceanBlue]

The difference is that the smoked fish you are buying in the store has been 'cured'... another method of preserving food. See: http://en.wikipedia.org/wiki/Curing_(food_preservation)