Removing the Seeds from Canned Tomatoes
I checked a few sites on the net about this and all mentioned that it seemed such a shame to waste all the juice during the seeding process. There process by the way was simply to cut the tomato in half and let seeds and juice drip out into the sink drain or a waste receptacle. None even mentioned the use of a food mill for this purpose. None of the sites mentioned seeding canned tomatoes either.
First of all I have never found the seeds to present a problem; they do not seem to make any difference in the taste or presentation. They do however get stuck in your teeth once in awhile. My wife makes excellent meat GRAVY and she never removes the seeds. She simply processes all right from the can into the blender. My mother in-law does the same except she does not use a blender; she dices all by hand removing only the stem and any pieces that she thinks will be bitter.
However you do want to remove the seeds for cream sauces such as Ala Vodka, and also for some soups.
I use primarily canned peeled tomatoes. I seed them by first slicing them down the center long ways and then gently scrape out the seeds using my very handy two-tinned fork, a small knife would work as well. I use two dishes; one to actually scrape the seeds, and the other to hold the seeded pieces. I then put all the tomato juice along with the removed seeds and any tomato pieces into my food mill and process all to obtain as much of the tomato juice as possible. I then discard all remaining stems and seeds from the food mill.
It takes about 10 minutes to seed one 28 can.