Process for treating sweet whey such as to obtain a protein material suitable for hypoallergenic infant formulae

1. A process for treatment of a sweet whey material containing cGMP (caseinoGlycoMacroPeptide), the process comprising:

decationising the sweet whey material to obtain sweet whey having a pH value of 1 to 4.5;

treating the sweet whey in a fluidized bed reactor comprising a specific volume of an anionic resin at a temperature between 10 and 18° C. and at a ratio of protein over resin of 0.20 to 0.35 kg/L, wherein the sweet whey contacts the anionic resin for a sufficient amount of time, so that the anionic resin absorbs between 52% and 58% of the cGMP present in the sweet whey and at least 90% of anions present in the sweet whey; and

recovering a protein material suitable for hypoallergenic infant formulae, the protein material comprising a tryptophan:threonine ratio between 0.350 and 0.360.

2. The process according to claim 1 , wherein the anionic resin absorbs around 55% of the cGMP.

3. The process according to claim 1 , wherein the anionic resin absorbs at least 90% of anions present in the sweet whey.

4. The process according to claim 3 , wherein the anions are selected from the group consisting of chlorine, phosphorous, citrate, sulphate, lactate, and combinations thereof.

5. The process according to claim 1 , wherein the anionic resin absorbs at least 90% of chlorine and of phosphorous anions present in the sweet whey.

6. The process according to claim 1 comprising treating the sweet whey in the fluidized bed reactor at a ratio of cGMP over resin between 39 and 41 g/L.

7. The process according to claim 1 , wherein the sweet whey material is selected from the group consisting of sweet whey obtained after separation of casein coagulated with rennet, a concentrate of sweet whey, a sweet whey demineralized by electrodialysis, ion exchange, reverse osmosis, electrodeionisation or a combination thereof, a concentrate of sweet whey demineralized by electrodialysis, ion exchange, reverse osmosis, electrodeionisation or a combination thereof, a concentrate of proteins of substantially lactose-free sweet whey obtained by ultrafiltration followed by diafiltration, mother liquors of the crystallization of lactose from sweet whey, a permeate of ultrafiltration of a sweet whey, a product of hydrolysis by a protease of a native casein obtained by acid precipitation of skimmed milk with an inorganic acid or by biological acidification obtained by microfiltration of a skimmed milk, a product of hydrolysis of a caseinate by a protease, and combinations thereof.

8. The process according to claim 1 , wherein the sweet whey has a solid content of about 10 to 30 percent by weight after decationisation.