Is Dry Oven Canning Safe?

The answer is NO.  As Wise Geek so elegantly explains this...

Oven canning is not safe because it is a dry heat and the jars are not made for that. They can explode. Contamination is the main fear when it comes to dry canning. In order for food to be shelf-stable, it must be heated to a hot enough temperature that any latent bacteria in the food is killed off. The premise behind dry canning is usually sound, as a 200°F oven is generally hot enough to be considered sterile. Not all oven thermometers are accurate, however, and it can be tough for home cooks to know whether the external temperature is actually penetrating the jars.

There is no way for cooks to test the internal jar temperature without removing the lids and compromising the food. Any bacteria that remains in sealed jars can grow into toxins over time, which can cause serious food poisoning once the contents is eventually consumed. Sometimes spoiled food looks discolored or has an unpleasant taste, but not always.

Then there is oil.  Some of the few things that have oil in them are nuts and seeds and even some flours.  The heat from the oven liquefies the oil making the product go rancid faster than if you had left it alone, which defeats the purpose.

Is it practical to use canning jars for dry good?

Lets pretend you have twenty, 1 pound bags of pinto beans and you want to store them air tight for long-term food storage.  Right off the bat you're going to have to buy, at minimum, two boxes of jars that run about $10-$15 each depending on where you live.  You will also have the added cost of using your electricity/gas to oven can your food.  Depending on how often and how much you can, that can raise your monthly bills considerably. 

Assuming you already have a vacuum sealer machine, a 3- 20 foot rolls of bags cost approximately $26.50, however, you will be able to seal and store much more.  Something else you might consider is instead of using the jars and the space they take up dry canning, use them for canning meat items and things you can not otherwise vacuum seal (Mmmmm, like salsa).  If you insist on storing your dry goods in jars then the safest and cheapest way to go would be to use an Oxygen Absorber in the jar and then use a vacuum seal jar attachment to remove air and seal the jar tightly.  If you do not have a vacuum sealer you can still add an Oxygen Absorber and then listen for the *ping* sound we all love about 15 minutes after you tighten the ring. The three most dangerous things you can do to your food storage is expose them to heat, light and moisture.  So why expose your food to heat if you don't have to?

In our home we use storage totes and five gallon buckets to store our dry goods.  When we vacuum seal the food in the bags we pack them tightly in a storage tote and once full we place the lid on them and stack them up. I love how light the tote is (depending on the food) compared to stacking and moving jars.  We typically use the vacuum sealer for items like crackers, drink mixes, tea bags, dried herbs, coffee, etc.  For things such as rice, beans, flour, and sugar we use the five gallon buckets with Mylar bags. 

As you can see, Dry Oven Canning can be more expensive, take up more space and can be very dangerous, as with any canning that does not practice safe, tried and true practices.  Keep your family safe and stick to methods that have been tested and proven safe.