Discoloured Golf Balls

Was up at my local course today and found a load of balls on my way round, it looked like the greenkeepers were killing time as the course was closed until noon, anyway I got the balls home around 15 Titleist Pro vs a few Nike,Pinacle and some others, quite a nice haul :D, any way after getting them home and cleaning them up the majority look like new, some though are discoloured off white, most likely they were in the Lake for a while, the question is would this have had any big effect on the performance of the ball or is it just ugly to look at lol