I don't know what causes it, but they sure look delish to me! Those yellow tastebombs are too small to squeeze out of their skin i guess. Maybe let them ripen a bit longer if it bothers you. Or stir fry them.
I've got this with 20 tomato green zebra plants but much worse, with hard vertical gushes. And they had bud rot, which i addressed by adding chalk to the
water. I cut them off and threw them on the
compost if it was bad. If it just started while they are ripe i read you can still use half the tomato. But the chalk made it better.
Then some got mosaics disease, i freaked out because i read it's very contagious and gave up watering them for a bit , but somehow it got contained to a few plants. And the whole
greenhouse is pumping out a kilo of delicious tomatoes a day with no end in sight, i share with friends and community now, all the perfect ones go to others.
Next year i'll prepare the soil better, and only plant the seeds of the good plants with little problems. See how that goes.
I also give bad tomatos to the
chickens, they'll pick the seeds out.