My first loaf!

Happy with how it turned out! Really delicious but seems like the crumb has a somewhat shiny look to it when I cut it open. Any idea of what that is or what I could do better?

400g KA bread flour, 100g KA whole wheat 375gish of water 75g of starter 10 g salt

Automate for 1 hour Mixed in starter and salt and don’t think I mixed it enough Fold 4x every 30 minutes for 2 hours, was not as stretchy as it looks in videos lol Proof for 4 hours in oven with light on Take out, shape, and put in fridge for 20 hrs Preheat cast iron Dutch oven for 1 hr at 500F Bake for 20 minutes with top on Down to 450F for 25 minutes, cooled for 4 hours