Oligosaccharide mixture

1. An oligosaccharide mixture derived from animal milk, the mixture comprising a lactose:oligosaccharide ratio of less than 250 and containing a spectrum of oligosaccharides that is the same as a spectrum of oligosaccharides of milk from which it was derived, wherein the mixture further comprises an oligosaccharide:β-galacto-oligosaccharide ratio ranging between 1:2 and 1:20.

2. The oligosaccharide mixture as claimed in claim 1 wherein the mixture has a lactose:oligosaccharide ratio of from 125 to 1.25.

3. The oligosaccharide mixture as claimed in claim 1 which is derived from a milk selected from the group consisting of cows' milk, goats' milk and buffalo milk.

4. The oligosaccharide mixture as claimed in claim 1 comprising β-galacto-oligosaccharides.

5. A food product comprising an oligosaccharide mixture derived from animal milk, the mixture comprising a lactose:oligosaccharide ratio of less than 250 and containing a spectrum of oligosaccharides that is the same as a spectrum of oligosaccharides of milk from which it was derived, wherein the mixture further comprises an oligosaccharide:β-galacto-oligosaccharide ratio ranging between 1:2 and 1:20.

6. The food product as claimed in claim 5 which is an infant food or formula.

7. A process for producing an oligosaccharide mixture, the process comprising:

(a) concentrating a deproteinised milk material to 50 to 75% total solids;

(b) subjecting the concentrated milk material to a lactose removal step to produce a liquor having a lactose:oligosaccharide ratio of less than 250; and

(c) demineralising the milk material to produce the oligosaccharide mixture derived from animal milk and having the same spectrum of oligosaccharides as the milk from which it was derived.

8. The process as claimed in claim 7 wherein step (b) comprises a lactose crystallisation step and a concentration step to remove lactose crystals and produce a liquor having a lactose:oligosaccharide ratio of less than 250.

9. The process as claimed in claim 7 wherein step (b) comprises spray-drying the deproteinised milk material and adding water to dissolve the oligosaccharides while leaving the lactose in a crystallised form.

10. The process as claimed in claim 7 wherein the deproteinised milk material is selected from the group consisting of a milk ultrafiltration permeate and a whey ultrafiltration permeate.

11. The process as claimed in claim 7 wherein the lactose removal step is repeated one or more times to further concentrate the liquor and eliminate lactose.

12. The process as claimed in claim 7 comprising treating the liquor product with individual proteases and/or combinations thereof to degrade any remaining milk proteins and peptides into entities with reduced molecular mass.

13. The process as claimed in claim 7 comprising treating the milk material with β-galactosidase to produce a whey material comprising β-galactosyl-oligosaccharides.

14. The process as claimed in claim 7 comprising treating the liquor product with β-galactosidase to produce a liquor comprising β-galactosyl-oligosaccharides.

15. The process as claimed in claim 13 , wherein the β-galactosidase is derived from Aspergillus oryzae.

16. The process as claimed in claim 7 comprising spray-drying the liquor product to produce powder.

17. The oligosaccharide mixture as claimed in claim 1 , wherein the mixture is derived from a deproteinised animal milk material.

18. The process as claimed in claim 7 , wherein concentration of the deproteinised milk material is carried out at a temperature of 50° C. to 90° C.