Water Activity (Aw): The Secret to Sourdough's Shelf Life
If you leave a slice of supermarket white bread on the counter, it will turn into a brick in 24 hours. If you leave it in a bag, it will grow blue fuzz in 3 days. But a loaf of sourdough, sitting cut-side down on a wooden board, behaves differently. It doesn't mould. It doesn't dry out instantly. It simply... ages.