Pasteurisation process for microbial cells and microbial oil

• US 8,895,708 B2
• Filed: 05/09/2012
• Issued: 11/25/2014
• Est. Priority Date: 06/19/2002
• Status: Expired due to Term

• Current Assignee: DSM IP Assets BV (DSM-Firmenich AG), DSM Services USA, Inc
• Original Assignee: DSM IP Assets BV (DSM-Firmenich AG)
• Inventors: Schaap, Albert, Verkoeijen, Daniel
• Primary Examiner(s): NAVARRO, ALBERT MARK
• Application Number:
  US13/467,843
• Publication Number:
  US 20120316354A1
• Time in Patent Office: 930 Days
• Field of Search: None
• US Class Current: 530/412
• CPC Class Codes: A23D 9/00 Other edible oils or fats, e.g. shortenings, cooking oils
• CPC Class Codes: A23D 9/02 characterised by the production or working-up
• CPC Class Codes: A23K 20/158 Fatty acids; Fats; Products containing oils or fats
• CPC Class Codes: A23L 33/115 Fatty acids or derivatives thereof; Fats or oils
• CPC Class Codes: A23L 33/12 Fatty acids or derivatives thereof
• CPC Class Codes: A61K 2800/85 Products or compounds obtained by fermentation, e.g. yoghurt, beer, wine
• CPC Class Codes: A61K 8/67 Vitamins
• CPC Class Codes: A61K 8/925 of animal origin
• CPC Class Codes: A61K 8/9706 Algae
• CPC Class Codes: A61K 8/9728 Fungi, e.g. yeasts
• CPC Class Codes: A61L 2/04 Heat A61L2/08 takes precedence
• CPC Class Codes: A61P 25/00 Drugs for disorders of the nervous system
• CPC Class Codes: A61P 43/00 Drugs for specific purposes, not provided for in groups A61P1/00-A61P41/00
• CPC Class Codes: A61Q 19/00 Preparations for care of the skin
• CPC Class Codes: C07C 57/03 Monocarboxylic acids
• CPC Class Codes: C11B 1/10 by extracting
• CPC Class Codes: C12N 1/005 after treatment of microbial biomass not covered by C12N1/02 - C12N1/08
• CPC Class Codes: C12P 7/6427 Polyunsaturated fatty acids [PUFA], i.e. having two or more double bonds in their backbone
• CPC Class Codes: C12P 7/6432 Eicosapentaenoic acids [EPA]
• CPC Class Codes: C12P 7/6434 Docosahexenoic acids [DHA]
• CPC Class Codes: C12P 7/6463 : obtained from glyceride producing microorganisms, e.g. single cell oil
• CPC Class Codes: C12P 7/6472 : containing polyunsaturated fatty acid [PUFA] residues, i.e. having two or more double bonds in their backbone

Abstract

A protocol for pasteurizing microbial cells is disclosed. The protocol has three stages, a first heating stage, a second plateau stage at which the cells are held at a (maximum and) constant temperature, and a third cooling stage. The heating and cooling stages are rapid, with the temperature of the cells passing through 40 to 80° C. in no more than 30 minutes in the heating stage. The heating rate is at least 0.5° C./minute and during cooling is at least −0.5° C./minute. The plateau maximum temperature is from 70 to 85° C. By plotting the pasteurization protocol on a time (t, minutes) versus temperature (T, ° C.) graph, a trapezium is obtained having an area less than 13,000° C. minute. This results in a smaller energy input and a better quality oil results having a peroxide value (POV) of less than 1.5 and an anisidine value (AnV) of less than 1.0.

Claims

1. A process for obtaining an oil comprising docosahexaenoic acid (DHA) from microbial cells, the process comprising

(a) a process for pasteurizing the microbial cells, which comprises heating the cells and so maintaining the cells at an elevated temperature at a plateau stage wherein the temperature at the plateau stage is above 100 °

C.; and

(b) extracting or isolating the oil from the pasteurized cells.

2. A process according to claim 1, wherein the temperature at the plateau stage is above 110 °

C.

3. A process according to claim 1, wherein the temperature at the plateau stage is from 100-160°

C.

4. A process according to claim 3, wherein the temperature at the plateau stage is from 110-160 °

C.

5. A process according to claim 3, wherein the temperature range at the plateau stage is from 100-140°

C.

6. A process according to claim 1, wherein (a) comprises maintaining the cells at an elevated temperature (T, °

C.) for a time (t, minutes) at a plateau stage wherein the product tT is from 140 to 100,800 °

C. minute.

7. A process according to claim 1, wherein the oil comprises at least 10% DHA.

8. A process according to claim 7, wherein the oil comprises at least 35% DHA.

9. A process according to claim 1, wherein (b) comprises extracting the oil from the pasteurized microbial cells using a solvent.

10. A process according to claim 1, wherein (b) comprises extracting a crude DHA-containing oil from the pasteurized cells and subjecting the crude oil to one or more refining steps.

11. A process according to claim 1, which further comprises incorporating the oil in a foodstuff, food supplement, or infant formula.

12. A process according to claim 1, which further comprises blending the oil with another oil.

13. A process according to claim 1, wherein the cells comprise a yeast, a bacteria, an algae and/or a fungi.

14. A process according to claim 1, wherein the cells comprise a dinoflagellate.

15. A process according to claim 1, wherein the cells comprise a Crypthecodinium.

16. A process according to claim 1, wherein the cells comprise a Thraustochytrium.

17. A process for obtaining an oil comprising at least 35% docosahexaenoic acid (DHA) from microbial cells, the process comprising

(a) a process for pasteurizing the microbial cells, which comprises heating the cells and so maintaining the cells at an elevated temperature at a plateau stage wherein the temperature at the plateau stage is above 80 °

C.; and

(b) extracting or isolating the oil from the pasteurized cells.

18. A process according to claim 17, wherein the temperature at the plateau stage is above 100 °

C.

19. A process according to claim 18, wherein the temperature at the plateau stage is above 110 °

C.

20. A process according to claim 17, wherein the temperature at the plateau stage is from 80-160 °

C.

21. A process according to claim 20, wherein the temperature at the plateau stage is from 100-160 °

C.

22. A process according to claim 21, wherein the temperature at the plateau stage is from 110-160 °

C.

23. A process according to claim 21, wherein the temperature at the plateau stage is from 100-140 °

C.

24. A process according to claim 17, wherein (a) comprises maintaining the cells at an elevated temperature (T, °

C.) for a time (t, minutes) at a plateau stage wherein the product tT is from 140 to 100,800 °

C. minute.

25. A process according to claim 17, wherein the cells comprise a yeast, a bacteria, an algae and/or a fungi.

26. A process according to claim 17, wherein the cells comprise a dinoflagellate.

27. A process according to claim 17, wherein the cells comprise a Crypthecodinium.

28. A process according to claim 17, wherein the cells comprise a Thraustochytrium.

29. A process according to claim 17, wherein the oil comprises at least 40% DHA.

30. A process according to claim 17, wherein (b) comprises extracting the oil from the pasteurized microbial cells using a solvent.

31. A process according to claim 30, wherein (b) comprises extracting a crude DHA-containing oil from the pasteurized cells and subjecting the crude oil to one or more refining steps.

32. A process according to claim 17, which further comprises incorporating the oil in a foodstuff, food supplement or infant formula.

33. A process according to claim 17, which further comprises blending the refined oil with another oil.