A method for producing a cheese with reduced amount of galactose
A technology of lactose and galactose, applied in the field of producing cheese with reduced galactose
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0149] Example 1 : ST Gal(+) bacteria - also able to greatly reduce the release of galactose in the presence of large amounts of lactose (eg in milk), i.e. the first aspect is the ST Gal(+) of step "(a)(I)" )bacteria
[0150] Reference strains:
[0151] - ST strain CHCC4323: has the so-called native wild-type sequence of GalK (referred to herein as GalK(-)), and can be considered as an ST reference strain, corresponding to the ST used commercially relevant today for the manufacture of mozzarella cheese strains;
[0152] - ST strain 4323-2 (CHCC14993): it contains a mutation in the GalK (galactokinase) gene (referred to herein as Gal(+)), which can be seen as corresponding to WO2011 / 026863A1 (Chr Hansen) and WO2011 / 092300A1 (Chr. Hansen) described the reference strains prepared strains.
[0153] Deposited strains
[0154] CHCC14994: DSM 25838 ST strain - disclosed in WO2013 / 160413A1 (Chr. Hansen).
[0155] CHCC19097: The new DSM 32594 ST strain described herein.
[...
Embodiment 2
[0190] Example 2: Method for obtaining "Lb.Gal(+)Lac(-) bacteria" of step "(a)(II)" of the first aspect - MRS criteria
[0191] L. delbrueckii subsp. lactis CHCC27906 was isolated as a lactose-negative mutant of the lactose-positive (and galactose-positive) wild-type strain L. delbrueckii subsp. lactis CHCC14951.
[0192] Cells of CHCC14951 were subjected to UV mutagenesis with a UV crosslinker (Energy 120MJ). Cells with a lethality of 99% (60 min UV treatment) were seeded on MRS-agar plates containing X-Gal. Lactose-positive colonies appear blue due to β-galactosidase activity, whereas lactose-negative mutants grow as white colonies.
[0193] A series of putative lactose-negative colonies were purified and retested in MRS supplemented with 1% lactose, 1% glucose as the only carbohydrate.
[0194] With an initial pH of 6.8, the final pH of CHCC14951 and the lactose-negative mutant CHCC27906 reached 4.2 after 18 hours at 37°C in MRS-glucose. CHCC14951 was acidified in a si...
Embodiment 3
[0200] Example 3: Compared with prior art using ST Gal(+) alone or using ST Gal(+) and Lb.Gal(+)Lac(+) co-culture, using ST Gal(+) and Lb.Gal(+) of the present invention ) Lac(-) Co-cultures lead to significantly higher % galactose reduction in milk
[0201] milk fermentation
[0202] The ST strain was grown in M17 as an overnight culture, while the lactose-negative Lb strain was pre-incubated overnight in MRS broth to receive a fully grown culture.
[0203] For co-cultivation experiments, when grown alone, ST strains were inoculated from overnight cultures at 1% in milk (pasteurized at 98°C / 30min, 9.5% total solids). In mixed cultures, the inoculum percentage was 0.75% for ST and 0.25% for Lb Gal(+)Lac(-) or Lb Gal(+)Lac(+) strains.
[0204] Incubation was performed at 37 °C for 16 hr. At the end of the fermentation, samples were taken to measure the galactose content in the fermented milk, the reduction in secreted galactose compared to the galactose negative refere...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More