Crusty beer bread

This rose all night, so is probably over-proved. The scent of baking bread in the morning is wonderful, though. I'm hungry because I didn't have time to taste it before rushing off to work.

200g wholemeal wheat flour
200g wholemeal spelt flour
200g white wheat flour
12g salt
12g caraway seed
400g Brown Beer
2 tbsp yeast gunge harvested from the bottom of the Brown Beer fermenting bucket

Bake at 200°C for 25 minutes, turning down to 150 for a further 20 minutes.