I've just found this website and it's great! I'm a keen amateur baker from the UK. I often use a bathe (cold water) when making SD breads, but I don't know why I do it - other than I've picked up the habit. My typical white SD recipe would be:
500g bakers flour (100%)
50g rye (10%)
130g starter at 100% hydration (26%)
290ml water at 5degC (58%)
90ml bathe (iced water) (18%)
10g sea salt (2%)
I add the bathe at the end of the initial kneading, just as the dough starts to come together. Can anyone explain what the bathe does?