Ultra-filtration, also known as UF, is a filtration process that uses a membrane to selectively concentrate protein, fat and insoluble salts. It is a pressure-driven crossflow filtration process in which the feed solution flows perpendicular to the direction of the filtrate flow. This process can be used to separate particles in the range of pore size 0.01- 0.1 µm with an operating pressure and temperature of 30 to 100 psi and 40 to 80 degrees Fahrenheit, respectively. The most common membrane types are polymeric (organic) and ceramic (inorganic).