Methods for casein production
Embodiments of the invention are directed to a process involving microfiltration of milk, providing a product that is useful as a source of casein and another product that is useful as a source of whey protein. Another embodiment of the invention is directed to preparing milk products like casein, dairy beverages, milk protein concentrates and cheese from microfiltration retentate.
1. A method for the production of a fraction containing micellar casein comprising the steps of:
a. filtering high temperature, short time (HTST) pasteurized skim milk by a microfiltration process in a uniform transmembrane pressure loop system, in which the HTST pasteurized skim milk is heated to a temperature of 73° C. for at least 15 seconds or 72° C. for at least 16 seconds, and wherein the starting product has a pH of 6.5 to 6.8, wherein the temperature of the system is maintained within the range of from 5° C. to 15° C., and wherein the pH is maintained at the same pH as the starting product, and wherein casein in the HTST pasteurized skim milk is concentrated 6-fold during microfiltration; and
b. separating the HTST pasteurized skim milk into a microfiltration permeate fraction comprising whey protein and a microfiltration retentate fraction comprising micellar casein, wherein the retentate fraction comprises a higher solids mass percentage of micellar casein and is depleted in whey protein as compared to the original skim milk,
wherein the method does not include an acidification step.
2. The method of claim 1 , wherein the microfiltration process is carried out using a membrane having a pore size of 20,000-200,000 daltons and a uniform transmembrane pressure of 10-40 psi.