I'm making a link here to a show that I've been watching on hulu.com, and this particular episode is about water, but for my interest it shows canning tuna in Italy. In this video there is only a short highlight of canning the tuna. It shows cooking the tuna in boiling water, scraping the skin off and boning the tuna, cutting it into pieces to fit the jars and putting the jars into a pot of water.
What I get from watching the video is that the tuna is packed in jars with screw tops unlike the canning jars we use in the U.S. but tops that things like our pickles from a store come in. I forget the different names for the different tops. Blast getting holes in my mind. Regardless of canning warnings from Ball, I frequently can things in recycled pickle-type jars. They seal. Period.
I also get that they are canning the tuna in a water bath. My Ball Blue Book calls for processing tuna in a pressure cooker for 1 hour and 40 minutes for half-pints or pints.
Now I know that the canning guides for the U.S. are litigation driven nowadays, and that the way people canned things in the past was different. People can argue that science is better, and we have more knowledge of bacteria, its survival and affect on our food than people used to have. It's still a subject that I ponder frequently.
At ORNL I worked with a man from a city west of Nashville, TN, and he used to talk about his youth and how his mother did things. He was from a large family, like, 14-15 siblings, and they weren't well off. He has talked about his mother canning fish whenever the kids brought a large one home, and she would pack the jars and cover them with melted, hot bacon fat or lard.
At one time I priced tuna for home canning. I was wondering how effective it would be cost-wise. My conclusion was that living in the middle of the country made buying fresh tuna prohibitive. Maybe if I lived on a coast and could go out fishing for tuna, it might be worthwhile. Otherwise, nah.
Here's the link to the video: http://www.hulu.com/watch/85506#i0,p0,s1,d0