Impact of ropy and capsular exopolysaccharide-producing strains of Lactococcus lactis subsp. cremoris on reduced-fat Cheddar cheese production and whey composition

The genome of Lactococcus lactis subsp. lactis bv. diacetylactis SD96, a strain used for cheese production, is presented. SD96 is refractory to phage attack, which is a desired property for starter bacteria. Its 10 plasmids provide industrially important traits, such as lactose and citrate metabolism, proteolytic activity, and phage resistance.

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Contribution of Lactococcus lactis Cell Envelope Proteinase Specificity to Peptide Accumulation and Bitterness in Reduced-Fat Cheddar Cheese

Applied and Environmental Microbiology ◽

10.1128/aem.68.4.1778-1785.2002 ◽

2002 ◽

Vol 68 (4) ◽

pp. 1778-1785 ◽

Cited By ~ 58

Author(s):

Jeffery R. Broadbent ◽

Mary Barnes ◽

Charlotte Brennand ◽

Marie Strickland ◽

Kristen Houck ◽

...

Keyword(s):

Lactococcus Lactis ◽

Cell Envelope ◽

Cheddar Cheese ◽

Gene Replacement ◽

Reversed Phase ◽

Reduced Fat ◽

Key Factor ◽

Industrial Strains ◽

Group A ◽

Or Gene

ABSTRACT Bitterness is a flavor defect in Cheddar cheese that limits consumer acceptance, and specificity of the Lactococcus lactis extracellular proteinase (lactocepin) is widely believed to be a key factor in the development of bitter cheese. To better define the contribution of this enzyme to bitterness, we investigated peptide accumulation and bitterness in 50% reduced-fat Cheddar cheese manufactured with single isogenic strains of Lactococcus lactis as the only starter. Four isogens were developed for the study; one was lactocepin negative, and the others produced a lactocepin with group a, e, or h specificity. Analysis of cheese aqueous extracts by reversed-phase high-pressure liquid chromatography confirmed that accumulation of αS1-casein (f 1-23)-derived peptides f 1-9, f 1-13, f 1-16, and f 1-17 in cheese was directly influenced by lactocepin specificity. Trained sensory panelists demonstrated that Cheddar cheese made with isogenic starters that produced group a, e, or h lactocepin was significantly more bitter than cheese made with a proteinase-negative isogen and that propensity for bitterness was highest in cells that produced group h lactocepin. These results confirm the role of starter proteinase in bitterness and suggest that the propensity of some industrial strains for production of the bitter flavor defect in cheese could be altered by proteinase gene exchange or gene replacement.

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The influence of phage-assisted lysis of Lactococcus lactis subsp. lactis ML8 on cheddar cheese ripening

International Dairy Journal ◽

10.1016/0958-6946(95)00022-u ◽

1995 ◽

Vol 5 (5) ◽

pp. 451-472 ◽

Cited By ~ 52

Author(s):

Vaughan L. Crow ◽

Frank G. Martley ◽

Tim Coolbear ◽

Sally J. Roundhill

Keyword(s):

Lactococcus Lactis ◽

Cheddar Cheese ◽

Lactococcus Lactis Subsp ◽

Cheese Ripening

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Addition to Thermized Milk of Lactococcus lactis subsp. cremoris M104, a Wild, Novel Nisin A–Producing Strain, Replaces the Natural Antilisterial Activity of the Autochthonous Raw Milk Microbiota Reduced by Thermization

Journal of Food Protection ◽

10.4315/0362-028x.jfp-13-521 ◽

2014 ◽

Vol 77 (8) ◽

pp. 1289-1297 ◽

Cited By ~ 10

Author(s):

ALEXANDRA LIANOU ◽

JOHN SAMELIS

Keyword(s):

Lactococcus Lactis ◽

Great Part ◽

Raw Milk ◽

Control Treatment ◽

Lactococcus Lactis Subsp ◽

Milk Samples ◽

Bulk Milk ◽

C 30 ◽

Sterilized Milk ◽

Cheese Production

Recent research has shown that mild milk thermization treatments routinely used in traditional Greek cheese production are efficient to inactivate Listeria monocytogenes and other pathogenic or undesirable bacteria, but they also inactivate a great part of the autochthonous antagonistic microbiota of raw milk. Therefore, in this study, the antilisterial activity of raw or thermized (63°C, 30 s) milk in the presence or absence of Lactococcus lactis subsp. cremoris M104, a wild, novel, nisin A–producing (Nis-A+) raw milk isolate, was assessed. Bulk milk samples were taken from a local cheese plant before or after thermization and were inoculated with a five-strain cocktail of L. monocytogenes (approximately 4 log CFU/ml) or with the cocktail, as above, plus the Nis-A+ strain (approximately 6 log CFU/ml) as a bioprotective culture. Heat-sterilized (121°C, 5 min) raw milk inoculated with L. monocytogenes was used as a control treatment. All milk samples were incubated at 37°C for 6 h and then at 18°C for an additional 66 h. L. monocytogenes grew abundantly (>8 log CFU/ml) in heat-sterilized milk, whereas its growth was completely inhibited in all raw milk samples. Conversely, in thermized milk, L. monocytogenes increased by 2 log CFU/ml in the absence of strain M104, whereas its growth was completely inhibited in the presence of strain M104. Furthermore, nisin activity was detected only in milk samples inoculated with strain M104. Thus, postthermal supplementation of thermized bulk milk with bioprotective L. lactis subsp. cremoris cultures replaces the natural antilisterial activity of raw milk reduced by thermization.

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USING LOCAL ISOLATES OF Lactococcus lactis subsp. lactis AND Lac. Lactis subsp. cremoris AS STARTERS IN CHEDDAR CHEESE PROCCESING

Basrah Journal of Agricultural Sciences ◽

10.33762/bagrs.2006.57312 ◽

2006 ◽

Vol 19 (2) ◽

pp. 99-110

Author(s):

G. H. Majeed ◽

A-M. M.Umran

Keyword(s):

Lactococcus Lactis ◽

Cheddar Cheese ◽

Lactococcus Lactis Subsp

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Autochthonous Enterococcus durans PFMI565 and Lactococcus lactis subsp. lactis BGBU1–4 in Bio-Control of Listeria monocytogenes in Ultrafiltered Cheese

Foods ◽

10.3390/foods10071448 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1448

Author(s):

Marina Ivanovic ◽

Nemanja Mirkovic ◽

Milica Mirkovic ◽

Jelena Miocinovic ◽

Ana Radulovic ◽

...

Keyword(s):

Lactic Acid ◽

High Temperature ◽

Listeria Monocytogenes ◽

Lactic Acid Bacteria ◽

Lactococcus Lactis ◽

Chemical Additives ◽

Enterococcus Durans ◽

Lactococcus Lactis Subsp ◽

Bacteriocin Producer ◽

Cheese Production

Nowadays, consumers are interested in cheese produced without chemical additives or high-temperature treatments, among which, protective lactic acid bacteria (LAB) cultures could play a major role. In this study, the aims were to isolate, identify and characterize antilisterial LAB from traditionally produced cheese, and utilize suitable LAB in cheese production. Among 200 isolated LAB colonies, isolate PFMI565, with the strongest antilisterial activity, was identified as Enterococcus durans. E. durans PFMI565 was sensitive to clinically important antibiotics (erytromicin, tetracycline, kanamycin, penicillin, vancomycin) and had low acidifying activity in milk. E. durans PFMI565 and the previously isolated bacteriocin producer, Lactococcus lactis subsp. lactis BGBU1–4, were tested for their capability to control Listeria monocytogenes in experimentally contaminated ultrafiltered (UF) cheeses during 35 days of storage at 4 °C. The greatest reductions of L. monocytogenes numbers were achieved in UF cheese made with L. lactis subsp. lactis BGBU1–4 or with the combination of L. lactis subsp. lactis BGBU1–4 and E. durans PFMI565. This study underlines the potential application of E. durans PFMI565 and L. lactis subsp. lactis BGBU1–4 in bio-control of L. monocytogenes in UF cheese.

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Cottage cheese fortified by natural additives

Food Research ◽

10.26656/fr.2017.5(s1).013 ◽

2021 ◽

Vol 5 (S1) ◽

pp. 152-159

Author(s):

R.S. Alibekov ◽

A.A. Utebaeva ◽

Z.T. Nurseitova ◽

Z.K. Konarbayeva ◽

B.M. Khamitova

Keyword(s):

Lactococcus Lactis ◽

Physicochemical Characteristics ◽

Fermented Milk ◽

Cottage Cheese ◽

Nutritional Values ◽

Lactococcus Lactis Subsp ◽

Organoleptic Characteristics ◽

Taste And Smell ◽

Cheese Production ◽

Natural Additives

Currently, a significant value for a correct nutrition and human metabolism has available the fermented milk products, as a cottage cheese that is produced by a culture of Lactis Lactococcus lactis subsp and Cremoris Lactococcus lactis subsp with pepsin. Moreover, the enrichment of the functional specificity of such products by vitamins C, E, A, D, K, macro - and microelements is a topical direction. The purpose of this study was to develop new cottage cheese compositions fortified by natural additives: ginger, topinambour and radish. For the achieving of it, following tasks were considered: creating of the cottage cheese production, sensory assessment, analyzing of the organoleptic and physicochemical characteristics, identifying of the macro- and microelements contents in the cottage cheese. From the available sources - ginger, topinambour and radish consist in following antioxidants: retinol (vitamin A), thiamine (B1), folacin (B9), riboflavin (vitamin B2), tocopherol (vitamin E), ascorbic acid (vitamin C) and others. The organoleptic characteristics, such as: appearance and consistency, taste and smell, colour and physicochemical properties confirmed that the developed compositions meet the standard requirements for cottage cheese. Specifically, the samples had a milky-white color, a pleasant uniform consistency with additives particles, without odour and a moderate taste. In addition, the mineral content in the cottage cheese was determined by the Massspectrometry method and using the Scanning Electron Microscope. The presented samples have nutritional values and following valuable macro- and microelements: potassium (15.43-26.90 mg/kg), calcium (6.83-14.37 mg/kg), magnesium (0.85-1.24 mg/kg), phosphorus 97.91-21.77 mg/kg), sodium (3.25-7.36 mg/kg) and others.

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