Abstract
Background: Whey is a watery part (serum) that remains after the coagulation of milk by acid or proteolytic enzymes and it contains mainly, lactose, proteins, minerals and water. Most of the countries have large dairy and cheese production units which generate huge amounts of whey per liter of milk processed. However, land disposal of whey as a waste product has been widely practiced all over the world that poses serious pollution problems. Thus, it is highly essential that whey has to be processed further to generate more valuable products and subsequently to make it suitable for safe disposal. The aim of the present study was to develop an economical method, so the dairy industry may adapt it to process whey to make it suitable for safe disposal.
Methods: The membrane chromatography was used to develop an economical method for the separation of whey proteins. Cellulose fiber treated with chlorosulfonic acid and commercially available adsorber Sartobind® S was used to optimize the separation of whey protein isolate.
Results: Dead end filtration study showed 1.02 mg / cm2 qm (maximum binding capacity) for cellulose fiber treated with chlorosulfonic acid and 1.3 mg / cm2 qm for Sartobind® S. Cellulose fiber showed 2.7% decrease in adsorption at 30th cycle whereas 26% decrease in adsorption was obtained at 8th cycle for Sartobind® S. The 19.0 fold higher surface area and 200 times higher feed volume was used for cross flow filtration study. It has showed 1.79 mg / cm2 qm for cellulose fiber and 3.2 mg / cm2 qm for Sartobind® S. The average flux was 543 ± 36 l / m2 / h for cellulose fiber and it was 43 ± 0.0 l / m2 / h for Sartobind® S. Electrophoresis of sample eluted at pH 7.0 showed three bands of major whey proteins for cellulose fiber whereas two bands for Sartobind® S. Cellulose fiber showed high potential for industrial applications.
Conclusion: In comparison to commercially available adsorber such as Sartobind® S, which has showed higher whey protein binding capacity (qm). The cellulose fiber treated with CSA appears to be more suitable for industrial applications. As it has shown higher flux (543 ± 36 l / m2 / h) and high flux regeneration capacity with minimum washings that ensures its longer life.
Keywords: Whey proteins, membrane adsorber, cellulose fiber, sartobind® S, flux regeneration, serum.
Graphical Abstract