Though not the best image (I was trying to get all these tomatoes in the stockpot), here’s a few Zapotec Pleated tomatoes (back), along with some San Marzanos (right) and what I think is a spontaneous cross between the two on the left.
Or, it’s possible it’s a “sport” of Zapotec. Either way, it’s a flavorful, productive tomato that has thick crack- and blemish-free skin, thick flesh, and very few seeds and juice–making it an excellent candidate for sauces and paste.
This is my main candidate for developing a stable new variety of my own. The other varietal experiments have more to do with improving an existing, stable variety–Red Pear (Red Fig) for a shorter, stumpier neck that’s less prone to cracking, and Polish Linguisa for a hardier, more productive strain.
To save tomato seeds, I use a couple of nice, squishy-ripe fruits–best if they come from more than one plant (ensuring more genetic diversity). You can save seeds from hybrids, but many of the plants will not be the same as the parents. Better to save seed from single variety parents (open-pollinated/heirlooms).
I usually use a half-pint canning jar for this process, but any small glass jar with a tight-fitting lid is a good candidate.
Cut open the fruits and squeeze the seeds into the jar. Try to avoid getting too many big clumps of flesh–this won’t harm the seed-saving process, but it does make it messier. Don’t try to fill the jar with seeds–just a thin layer at the bottom of the jar is enough.
Then, fill the jar with clean tap water (leave an inch or so for “shake room.” Tighten the lid and shake the jar, then leave it on the counter out of direct sunlight for a couple days, shaking well each day. Label the jar with the variety.
When you start getting a layer of “crud” at the top (probably the second day), separate from the seeds at the bottom, pour that off and refresh the water, then shake again. You only need to leave the seeds in the jar three days or so–just long enough to dissolve the gelatinous coating on the seeds.
Once the seed coating looks to have dissolved, pour the water out of the jar slowly, in order to leave the seeds in the bottom with as little water as possible. Take a small (dessert-sized) plate, reach into the jar, and scrape the seeds out onto the plate–separating them as much as possible (they will usually clump a bit). Put a Post-it or other label on the plate with variety info.
I put the seeds on the plate on top of my refrigerator, where it’s dark-ish and dry. I’ll usually go through them with my fingers on the second or third day of drying to try to separate any clumps a little more (this makes it a lot easier to sow the seeds next season).
Once the seeds are dry–three days to a week, depending on your humidity level–package the seeds in an envelope or jar, label with variety, date, and any other notes, and store in cool, dry, dark conditions.