i made oat milk yesterday, the recipe said soak 24-36 hours drain add more water, blend with sweetner cinamon and vanilla. i like the color and texture but its sour. i actually let it soak an extra 10hours but not on purpose. do you think that's why its sour or is it always sour? also the thicker stuff seems to separate when it sets in the fridge will i have to shake it each time?