Lactic bacterium for texturizing food products selected on the basis of phage resistance

• US 9,562,221 B2
• Filed: 02/17/2016
• Issued: 02/07/2017
• Est. Priority Date: 01/28/2010
• Status: Active Grant

• Current Assignee: CHR Hansen Holding A/S
• Original Assignee: CHR Hansen Holding A/S
• Inventors: Janzen, Thomas, Christiansen, Ditte Ellegaard
• Primary Examiner(s): Monshipouri, Maryam
• Application Number:
  US15/045,932
• Publication Number:
  US 20160227803A1
• Time in Patent Office: 356 Days
• US Class Current: 1/1
• CPC Class Codes: A23C 2220/202 Genetic engineering of microorganisms used in dairy technology
• CPC Class Codes: A23C 9/1209 Proteolytic or milk coagulating enzymes, e.g. trypsine
• CPC Class Codes: A23C 9/123 using only microorganisms of the genus lactobacteriaceae; Yoghurt A23C9/13 takes precedence
• CPC Class Codes: A23C 9/1238 using specific L. bulgaricus or S. thermophilus microorganisms; using entrapped or encapsulated yoghurt bacteria; Physical or chemical treatment of L. bulgaricus or S. thermophilus cultures; Fermentation only with L. bulgaricus or only with S. thermophilus
• CPC Class Codes: A23V 2400/11 Lactobacillus
• CPC Class Codes: A23V 2400/123 Bulgaricus
• CPC Class Codes: A23V 2400/143 Fermentum
• CPC Class Codes: A23V 2400/249 Thermophilus
• CPC Class Codes: C12N 1/20 Bacteria; Culture media therefor
• CPC Class Codes: C12N 1/205 Bacterial isolates
• CPC Class Codes: C12N 15/01 Preparation of mutants without inserting foreign genetic material therein; Screening processes therefor
• CPC Class Codes: C12N 15/746 for lactic acid bacteria (Streptococcus; Lactococcus; Lactobacillus; Pediococcus; Enterococcus; Leuconostoc; Propionibacterium; Bifidobacterium; Sporolactobacillus)
• CPC Class Codes: C12N 9/1205 Phosphotransferases with an alcohol group as acceptor (2.7.1), e.g. protein kinases
• CPC Class Codes: C12Q 1/14 Streptococcus; Staphylococcus
• CPC Class Codes: C12R 2001/225 Lactobacillus
• CPC Class Codes: C12R 2001/46 Streptococcus ; Enterococcus; Lactococcus
• CPC Class Codes: C12Y 207/01006 Galactokinase (2.7.1.6)

Abstract

The present invention relates to a bacterial cell with texturizing property, starter cultures comprising the cell, and dairy products fermented with the starter culture.

Claims

1. A method for producing a fermented milk or dairy product comprising:

fermenting a milk or dairy substrate with (i) a Streptococcus thermophilus bacterium comprising a galactokinase (GalK) gene having a −

10 region having a nucleotide sequence selected from the group consisting of TATGAT (SEQ ID NO;

8), TATTAT (SEQ ID NO;

9) and TACTAT (SEQ ID NO;

10) and (ii) a Lactobacillus delbrueckii ssp. bulgaricus bacterium.

2. The method of claim 1, wherein the Streptococcus thermophilus bacterium is CHCC11379 having deposit accession number DSM 22884.

3. The method of claim 1, wherein the Lactobacillus delbrueckii ssp. bulgaricus bacterium is selected from the group consisting of CHCC10019 having deposit accession number DSM 19252, CHCC2008 having deposit accession number DSM 22584, and CHCC3984 having deposit accession number DSM 19251.

4. The method of claim 1, further comprising adding an enzyme to the milk or dairy substrate.

5. The method of claim 4, wherein the enzyme is selected from the group consisting of an enzyme able to crosslink proteins, transglutaminase, an aspartic protease, chymosin, and rennet.

6. The method of claim 1, wherein the fermented milk or dairy product has an increased viscosity and/or increased gel stiffness relative to a milk or dairy product produced via a comparable method but with a Streptococcus thermophilus bacterium having a GalK gene that does not have a −

10 region having a nucleotide sequence selected from the group consisting of SEQ ID NO;

8, SEQ ID NO;

9 and SEQ ID NO;

10.

7. The method of claim 1, wherein the milk or dairy substrate is fermented with the Streptococcus thermophiles bacterium before and/or during fermentation with the Lactobacillus delbrueckii ssp. bulgaricus bacterium.

8. The method of claim 1, wherein the milk or dairy substrate is fermented with the Streptococcus thermophilus bacterium after fermentation with the Lactobacillus delbrueckii ssp. bulgaricus bacterium.

9. The method of claim 4, wherein the enzyme is added before and/or during fermentation.

10. A method for producing a fermented milk or dairy product comprising:

fermenting a milk or dairy substrate with (i) a Lactobacillus delbrueckii ssp. bulgaricus bacterium and (ii) a mutant Streptococcus thermophilus bacterium comprising a mutated galactokinase (GalK) gene having a −

10 region wherein one or both of C and G of the wildtype GalK gene −

10 region (TACGAT, SEQ ID NO;

     7) is replaced with a nucleotide independently selected from the group consisting of A and T.

11. The method of claim 10, wherein the Streptococcus thermophilus bacterium is CHCC11379 having deposit accession number DSM 22884.

12. The method of claim 10, wherein the fermented milk or dairy product has a higher viscosity and/or higher gel stiffness than a milk or dairy product produced via a comparable method but with a wildtype Streptococcus thermophilus bacterium.

13. The method of claim 12, wherein the fermented milk or dairy product has a viscosity of at least 70 Pa when measured as shear stress after 12 hours of growth at 37°

C.

14. The method of claim 10, further comprising adding an enzyme to the milk or dairy substrate.

15. The method of claim 14, wherein the enzyme is selected from the group consisting of an enzyme able to crosslink proteins, transglutaminase, an aspartic protease, chymosin, and rennet.

16. The method of claim 10, wherein the milk or dairy substrate is fermented with the Streptococcus thermophilus bacterium before and/or during fermentation with the Lactobacillus delbrueckii ssp. bulgaricus bacterium.

17. The method of claim 10, wherein the milk or dairy substrate is fermented with the Streptococcus thermophilus bacterium after fermentation with the Lactobacillus delbrueckii ssp. bulgaricus bacterium.

18. The method of claim 14, wherein the enzyme is added before and/or during fermentation.

19. A method for producing a fermented milk or dairy product comprising fermenting a milk or dairy substrate with:

(i) Streptococcus thermophilus bacterium CHCC11379 having deposit accession number DSM 22884 and

(ii) a Lactobacillus delbrueckii ssp. bulgaricus bacterium selected from the group consisting of CHCC10019 having deposit accession number DSM 19252, CHCC2008 having deposit accession number DSM 22584, and CHCC3984 having deposit accession number DSM 19251.

20. The method of claim 19, wherein the fermented milk or dairy product has a higher viscosity and/or higher gel stiffness than a milk or dairy product produced via a comparable method but with a wildtype Streptococcus thermophilus bacterium.