Editing Ultrafiltration (section)

=== Protein concentration ===
UF is used extensively in the dairy industry;<ref>{{cite journal |last1=Villecco F., Aquino R.P., Calabrò V., Corrente M.I., D’Amore M., Grasso A., Naddeo V. |title=Fuzzy-assisted ultrafiltration of whey by-products recovery |journal=Euro-Mediterranean Journal for Environmental Integration |year=2020 |volume=5 |issue=1 |page=8 |doi=10.1007/s41207-019-0138-5 |bibcode=2020EMJEI...5....8V |s2cid=212655195 }}</ref> particularly in the processing of cheese whey to obtain [[whey protein concentrate]] (WPC) and lactose-rich permeate.<ref name=Tamime>{{cite book|last=Tamime|first=A. Y.|title=Membrane Processing Dairy and Beverage Applications.|date=12 December 2012|publisher=Wiley|location=Chicester|isbn=978-1118457023}}</ref><ref name=Nigam>{{cite journal|last1=Nigam|first1=Mayank Omprakash|author2=Bansal, Bipan |author3=Chen, Xiao Dong |title=Fouling and cleaning of whey protein concentrate fouled ultrafiltration membranes|journal=Desalination|date=1 January 2008|volume=218|issue=1–3|pages=313–322|doi=10.1016/j.desal.2007.02.027|bibcode=2008Desal.218..313N }}</ref> In a single stage, a UF process is able to concentrate the whey 10–30 times the feed.<ref name=HB>{{cite book|last=Cheryan|first=Munir|title=Ultrafiltration and Microfiltration Handbook|year=1998|publisher=CRC Press|isbn=1420069020}}</ref><br />
The original alternative to membrane filtration of whey was using steam heating followed by drum drying or spray drying. The product of these methods had limited applications due to its granulated texture and insolubility.  Existing methods also had inconsistent product composition, high capital and operating costs and due to the excessive heat used in drying would often denature some of the proteins.<ref name=Tamime /><br />
Compared to traditional methods, UF processes used for this application:<ref name=Tamime /><ref name=HB />
:*Are more energy efficient
:*Have consistent product quality, 35–80% protein product depending on operating conditions
:*Do not denature proteins as they use moderate operating conditions
The potential for fouling is widely discussed, being identified as a significant contributor to decline in productivity.<ref name=Tamime /><ref name=Nigam /><ref name=HB /> Cheese whey contains high concentrations of calcium phosphate which can potentially lead to scale deposits on the membrane surface. As a result, substantial pretreatment must be implemented to balance pH and temperature of the feed to maintain solubility of calcium salts.<ref name=HB /><ref>Ann-Sofi Jönsson, Gun Trägårdh,
Ultrafiltration applications,
Desalination,
Volume 77,
1990,
Pages 135-179,
ISSN 0011-9164,
https://doi.org/10.1016/0011-9164(90)85024-5</ref>
[[Image:ultra filtration.JPG|thumb|right|200px|A selectively permeable [[Membrane (selective barrier)|membrane]] can be mounted in a [[Laboratory centrifuge|centrifuge tube]]. The [[buffer solution|buffer]] is forced through the membrane by [[centrifugation]], leaving the [[protein]] in the upper chamber.]]