Tomato plant
From Self-sufficiency
Saving seeds
Version 1
To save tomato seeds cut out the center, use as much of the tomato as you can, run the center with seeds thou a sieve in cold water. Use your hands and just water until the seeds are clean of any pulp. Then spread them out on a screen or paper towel to dry. Make sure they're thoroughly dry before packaging. Package in paper and be sure and write on it when what they are and when you saved them.
Version 2
Squeeze the seeds in a jar pulp and all and it has to ferment for 3 weeks or until mold grows on top, when that happens you rinse the seeds in a sieve and dry on a paper towel, I was told by a expert you always have to ferment the seeds first.