I've soaked some beans in room temperature water overnight, since 6pm (white navy beans).
How long can I keep them in water before I must use them?
Will they last a day or so at room temperature and in water, or should I drain and store in the fridge, or must I cook with them immediately?
It rather depends on the temperature of the room. Where I live, in the summer it gets hot and humid, and they shouldn't be out on the counter during the day, or they ferment. In winter (like spring in the northern US, 45-70 farenheit) they can be out for two days with no problem.
My recommendation would be to soak overnight for morning use, or to soak during the day for evening use. It also helps to change the water every few hours, though this isn't critical. If you refrigerate them with the water, you get an extra half-day. Refrigerating drained gets another day or so.
Either way, they should always be shaded, never in direct sunlight.
If they do spoil, you'll know, as they'll have a sour/yeasty smell to them.
I have soaked mine many times up to 2.5 days until I could get to them. I always plan to soak for 1 to 1.5 days (overnight then cook the next evening would be 1.5 days) but life happens so I just change the water and soak (on my countertop) another 24 hours without any problems. I do soak my beans in water with some apple cider vinegar and salt, the traditional way of soaking to remove inherent toxins. Maybe this make them last longer to soak for a longer time. Ive also soaked overnight, then realized I couldnt make them for a few days and simply put them in clean water in the refrigerator for up to 3 more days (changing the water daily).
