However, albumin is lost at each process stage, with roughly 20% of the albumin lost through precipitation stages before fraction V. In order to purify the albumin, there is an extraction with water, and adjustment to 10% ethanol, pH of 4.5 at −3 °C. Any precipitate formed here is done so by filtration and is an impurity. These precipitates are discarded. Reprecipitation, or repetition of the precipitation step in order to improve purity, is done so by raising ethanol concentration back to 40% from the extraction stage. The pH is 5.2 and it is conducted at −5 °C. Several variations of Cohn fraction were created to account for lower cost and higher yield. Generally, if the yield is high, the purity is lowered, to roughly 85-90%.