Baking with whey
I have a yogurt strainer that I use to make Greek yogurt or yogurt cheese (lebneh). The whey drips out of the yogurt, into the box that holds the strainer.
Yesterday I felt experimental and used this whey instead of water when I made my usual ciabatta bread. The whey was thicker than usual, because the yogurt I'd bought had been thickened with pectin rather than allowed to thicken on its own; I won't be buying THAT brand again. The whey was FULL of lactose and some milk solids.
The dough rose enthusiastically (all the extra sugars, I think) but didn't have as much oven spring as usual. The bread is moist and tasty.
In the future, I'll be baking with the whey, but keeping on eye on the dough to make sure that it doesn't over-rise.