I need to know about canning in the oven. I have everything but the how long to leave in the oven? I know the temp is 200 just don't know how long to leave in the oven.
I know this thread is a little old but I thought it worth a comment anyway, particularly as it still forms a reference to those looking for information.
Firstly, I can't possibly see why food in a glass jar which is placed in an oven for long enough won't reach the desired temperature throughout. If I thought that it wouldn't, I'd never eat a roast chicken ever again !!! I'm a physics teacher and heat is transferred if there is a gradient i.e. like water, it will "flow" either up or down with time and temp difference. The bigger the temp difference the quicker it will flow. You need to realise that we are talking about heat flowing through the liquid inside the jar and not the air in the oven. Heat transfer through the air in the oven is irrelevant as it is already at the desired temperature which is then maintained by the elements.
Here are the questions asked by community members. Read on to see the answers provided by the ThriftyFun community.
I have heard you can use your oven instead of a hot bath for canning and wonder if it's true? It would be a lot easier, but I don't know what to do as far as safety and oven temperature and time. Any ideas?
By Jennifer
Yes, yes, yes. I put my jars, rings and lids on a large sturdy cookie sheet, adjust shelves in oven to size of your jars. Ball says 250 degrees F, I use 300 degrees F and about 20 minutes. Works very well.
Yes! Prepare everything as usual. Place in sterilized jars & put on seals. Put into a cold oven. Turn oven to 250 degrees for 45 minutes. Turn off off and let sit inside oven overnight.
I would like to can olives in the oven. On what temperature should I put the oven? And how long do they need to stay in the oven?
Oven canning is not considered safe...at least I would never do it.
You have to scroll down to find it, but this site weighs in on the danger:
nchfp.uga.edu/
Ovens don't keep temperature and this can be VERY DANGEROUS for preserving foods.
I like olives pickled and when I have extras I drop them into the brine left after I eat the pickles. They don't keep really long, but get a nice tang to them.
If you want real canning recipes (like with the heat bath etc.) this site has recipes.
pickyourown.org/
I got sick once from improperly canned food and it was AWFUL....please process safely!! Thanks!
What is canning in the oven? How do you go about doing this? I have for a long time been interested in canning. This may be something I may want to do. Please someone reply. Thank you.
By Warren from Prince Albert, Saskatchewan, Canada
Oven canning means processing the filled jars in the oven as opposed to a boiling water bath or pressure canner. However, unlike the other two methods it isn't considered safe. Ovens don't provide the reliable, even heat required to kill some nasty bacteria including botulism. Plus jars may crack or even explode. Some people do use this method but it isn't recommended.
Canning is a great thing to do and I hope you try it out! Do an online search for the USDA guide Principles of Home Canning or try the Ball Blue Book to start out.
My mother and I recently canned a vegetable stew. She swears by the oven canning method and so we did that. We kept everything hot from the stew, to the jars (kept hot in the oven before canning) and then placing them back into the oven at 350 C for another 30 min.
My question is, why is this method not recommended even with everything being consistently hot? I would imagine everything would be killed off.The recommended method for canning vegetables is pressure canning. Oven canning is not recommended. Botulism could develop with your method. Discard this stew for the sake of your health and invest in a pressure canner.
nchfp.uga.edu/
Here are two links that talk about why the oven method is not a good idea. The uneven temperatures is the biggest reason...this means that some of the food could be dangerous to consume because it wasn't heated correctly.
Having gotten sick from something canned the right way and still was a fail, I encourage people to can safely, follow recipes exactly and to follow only approved canning methods.
SAFETY FIRST!!! I would not eat anything canned in this method so you may want to discard what was canned this way.
This method is a thing of the past and sometimes we all have to rethink what we believe to be tried and true and perhaps never failed us in the past (?).
It is probably true that your mother has never known of anyone to get sick due to eating food canned by this method but that does not mean it could not happen with what you have just prepared.
Apparently there were cases of food poisoning and this method was deemed the culprit (CDC) so after many trials of this and other methods it was found that canning in the oven was many times not safe and this method should not be used.
Please convince your mother that if you intend to do canning in the future to please purchase proper canning equipment so there will be no danger of botulism (if instructions are followed properly).
I'm sorry if your food has to be discarded but most likely; someone will eat some of it just to prove that it is safe - if that does happen - I hope it is..
I see no reason not to oven can DRY foods. The point of a pressure canner is that you can achieve a higher boiling point for liquids. Under 10psi you will increase the temperature to around 240 degrees. You cannot achieve that in an oven since there is no pressure and liquid boilsat around 212 based on atmospheric pressure.
However for dry ingredients you certainly can achive 240 or higher in an oven. The other issue is that water is denser than air so transfer of heat is better, but this can be overcome by adding time. They also claim temperature fliufuation is greater which is also true since the thermocouple used to turn the oven on and off turns heat into low voltage must hit the lower limit to turn the element or gas back on. But again simply using a probe thermometer to see how your oven performs and putting the temp as high as you need to keep the lower limit above the temp required.
So for dry ingredients with a little thought put into the process it would be completely safe.
If it hasn't been long, just dump in bags and freeze if you are worried.
Can you can cornmeal and oatmeal in Mason jars in the oven?
According to the Pepper Project this is an excellent way to store dry foods for years. Oven canning is very popular for rice, oatmeal, cornmeal and other dry foods. Here is a link if you would like to learn more.
I canned beef several years ago in the oven in pint jars. I can't remember the degrees or time. The lady I got the recipe from died and I lost it. I can't remember if it was 250 degrees for 3 hours or what.
I know she told me to keep the jars in the oven overnight and they would seal. She said not to open the oven till morning.Canning meat in the oven is not recommended. You need to can meat in a pressure canner.
I make pickles beets mustard beans etc and have my jars and lids in the oven 200 degrees. I fill one jar at a time with food and then wipe the top of jar and then grab the hot lids and put on tight. They pop as they cool and they are complete. Im making spaghetti sauce now and will do the same. Ill have the hot spaghetti sauce and then grab one hot jar from the oven, pour the sauce in, wipe the top and then grab a lid and ring from the oven. Put on top and tighten. As it cools the lid pops. This is the way I do my canning with no problems. I feel more scared doing a hot bath method.
I oven canned sweet potatoes very successfully a few years ago but cant remember how long I left the oven on. How long do you do it for?
