Process steps for the preparation of purified fractions of alpha-lactalbumin and beta-lactoglobulin from whey protein concentrates.
Fractions enriched with alpha-lactalbumin (alpha-la) and beta-lactoglobulin (beta-lg) were produced by a process comprising the following successive steps: clarification-defatting of whey protein concentrate, precipitation of alpha-lactalbumin, separation of soluble beta-lactoglobulin, washing the precipitate, solubilization of the precipitate, concentration and purification of alpha-la. The present study evaluated the performance of the process, firstly on a laboratory scale with acid whey and then on a pilot scale with Gouda cheese whey. In both cases soluble beta-lg was separated from the precipitate using diafiltration or microfiltration and the purities of alpha-la and beta-lg were in the range 52-83 and 85-94% respectively. The purity of the beta-lg fraction was higher using acid whey, which does not contain caseinomacropeptide, than using sweet whey. With the pilot scale plant, the recoveries (6% for alpha-la; 51% for beta-lg) were disappointing, but ways of improving each step in the process are discussed.
Gésan-Guiziou
G
G
INRA, Laboratoire de Recherches de Technologie Laitière, Rennes, France.
Daufin
G
G
Timmer
M
M
Allersma
D
D
van der Horst
C
C
D002611:Cheese / Q000032:analysis; D011232:Chemical Precipitation; D005374:Filtration; D006863:Hydrogen-Ion Concentration; D007136:Immunoglobulins / Q000737:chemistry; D007768:Lactalbumin / Q000737:chemistry / Q000302:isolation & purification*; D007782:Lactoglobulins / Q000302:isolation & purification*; D008894:Milk Proteins / Q000737:chemistry*; D009994:Osmolar Concentration; D012710:Serum Albumin, Bovine / Q000737:chemistry; D012995:Solubility; D000067816:Whey Proteins
D007136:Immunoglobulins; D007782:Lactoglobulins; D008894:Milk Proteins; D000067816:Whey Proteins; D012710:Serum Albumin, Bovine; D007768:Lactalbumin