In an attempt to be more self-sustaining in my gardening efforts, I have decided to save tomato seeds to plant next year. Apparently, only heirloom tomato seeds will produce the same tomato that the seeds came from. Most tomato seeds sold in stores are hybrid, and may give different results (which would make for some interesting Frankenstein-type experiments, I suppose). However, I had Black Krim and Brandywine tomatoes this year, both of which meet my needs.
Step 1: Use your best looking tomatoes (what you sow so shall you reap!). Remove seeds from tomatoes and place in a shallow container (preferably with a lid) - don't worry about separating them from the gel, that comes later.
Step 2: Cover with water.
Step 3: Let sit around for 3-5 days to develop mold.
Step 4: Remove the mold cap and and any floating seeds.
Step 5: Rinse seeds using a fine mesh strainer, but don't go crazy trying to remove the gel, not a big deal. It's hard to see in the picture but I'm using one of those dollar-store nylon strainers here.
Step 6: Spread seeds on a plate to dry - they stick to paper towels or regular dinner plates; paper plates are supposed to be the best. I did not have paper plates so risked it with the regular plate - I definitely had more than a few that stuck to the plate. I imagine the outer layer of the seed has been damaged and won't germinate but I can't tell which ones they were so I've just kept them all.
Step 7: When fully dry, place in an envelope and label. Store in a cool, dry place.
Step 8: Keep fingers crossed that they will germinate next year!!