Purification of the two major proteins from whey concentrate using a cation-exchange selective adsorption process

Separation Technologies for Whey Protein Fractionation

Whey is a by-product of cheese, casein, and yogurt manufacture. It contains a mixture of proteins that need to be isolated and purified to fully exploit their nutritional and functional characteristics. Protein-enriched fractions and highly purified proteins derived from whey have led to the production of valuable ingredients for many important food and pharmaceutical applications. This article provides a review on the separation principles behind both the commercial and emerging techniques used for whey protein fractionation, as well as the efficacy and limitations of these techniques in isolating and purifying individual whey proteins. The fractionation of whey proteins has mainly been achieved at commercial scale using membrane filtration, resin-based chromatography, and the integration of multiple technologies (e.g., precipitation, membrane filtration, and chromatography). Electromembrane separation and membrane chromatography are two main emerging techniques that have been developed substantially in recent years. Other new techniques such as aqueous two-phase separation and magnetic fishing are also discussed, but only a limited number of studies have reported their application in whey protein fractionation. This review offers useful insights into research directions and technology screening for academic researchers and dairy processors for the production of whey protein fractions with desired nutritional and functional properties.

Isolation and purification of beta-lactoglobulin from cow milk

Aim:

The present study was undertaken to standardize a convenient method for isolation and purification of β-lactoglobulin (β-lg) from cow milk keeping its antigenicity intact, so that the purified β-lg can be used for detection of cow milk protein intolerance (CMPI).

Materials and Methods:

Raw milk was collected from Gir breed of cattle reared in Haringhata Farm, West Bengal. Milk was then converted to skimmed milk by removing fat globules and casein protein was removed by acidification to pH 4.6 by adding 3 M HCl. β-lg was isolated by gel filtration chromatography using Sephacryl S-200 from the supernatant whey protein fraction. Further, β-lg was purified by anion-exchange chromatography in diethylaminoethyl-sepharose. Molecular weight of the purified cattle β-lg was determined by 15 percent one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis and was analyzed by gel documentation system using standard molecular weight marker.

Results:

The molecular weight of the purified cattle β-lg was detected as 17.44 kDa. The isolated β-lg was almost in pure form as the molecular weight of purified β-lg monomer is 18kDa.

Conclusion:

The study revealed a simple and suitable method for isolation of β-lg from whey protein in pure form which may be used for detection of CMPI.