The first of my winter growouts of my F1 plants are just finishing off, and I've been harvesting seed. I've been away for a month and half, and some pods matured on the plants, with the seeds inside the pods germinating in the pod - most disappointing. But I seem to have enough (more than enough, actually) to get a good crop of F2 plants to assess.
For one cross, Chamber of Death X Delta Louisa, I harvested seed last week. Subsequently inspecting the seed, I noticed 2 classes of seed - wrinkled, which are blocky and wrinkly; and dimpled, which are mostly round with only a slight dimple in the seed coat. When I harvested the seed I put it down to early harvesting of pods, and thought the wrinkled ones were just under developed. But I don't think so. Wrinkled seed coat is associated with sweet flavour (I seem to recall that it's got to do with starch development which affects both flavour and how the starch gets 'packed' in the seed).
I'm going to sow them separately, to see if they segregate for flavour.
I subsequently googled this, and found wrinkled seed was one of the characteristics Mendel used in his original experiments. It's also a embryonic trait - you can tell if the F3 plants will have the gene by looking at the seed off the F2 plants. This helps if you want to select for sweetness, and want to limit your growouts, both of which I want. But I'll see how I go growing both for this line, to see if it works out.
My other F2 growouts from my summer growing seed are just setting pods now - I do have some purples, but can't tell if they are snows, yet. All of my plants are suffering from powdery mildew, and it might be a bit late to spray with Potassium Bicarbonate, but I will give it a go this week.