Comparison of growth and survival of single strains of Lactococcus lactis and Lactococcus cremoris during Cheddar cheese manufacture

Clostridium tyrobutyricum spores survive milk pasteurization and cause late blowing of cheeses and significant economic loss. The effectiveness of nisin-producing Lactococcus lactis ssp. lactis 32 as a protective strain for control the C. tyrobutyricum growth in Cheddar cheese slurry was compared to that of encapsulated nisin-A. The encapsulated nisin was more effective, with 1.0 log10 reductions of viable spores after one week at 30 °C and 4 °C. Spores were not detected for three weeks at 4 °C in cheese slurry made with 1.3% salt, or during week 2 with 2% salt. Gas production was observed after one week at 30 °C only in the control slurry made with 1.3% salt. In slurry made with the protective strain, the reduction in C. tyrobutyricum count was 0.6 log10 in the second week at 4 °C with both salt concentration. At 4 °C, nisin production started in week 2 and reached 97 µg/g after four weeks. Metabarcoding analysis targeting the sequencing of 16S rRNA revealed that the genus Lactococcus dominated for four weeks at 4 °C. In cheese slurry made with 2% salt, the relative abundance of the genus Clostridium decreased significantly in the presence of nisin or the protective strain. The results indicated that both strategies are able to control the growth of Clostridium development in Cheddar cheese slurries.

Download Full-text

The Growth and Survival of Streptococcus Faecalis in Pasteurized Milk American Cheddar Cheese

Journal of Dairy Science ◽

10.3168/jds.s0022-0302(48)92206-1 ◽

1948 ◽

Vol 31 (4) ◽

pp. 285-292 ◽

Cited By ~ 11

Author(s):

F.V. Kosikowsky ◽

A.C. Dahlberg

Keyword(s):

Cheddar Cheese ◽

Streptococcus Faecalis ◽

Growth And Survival ◽

Pasteurized Milk

Download Full-text

Role of Enterococci in Cheddar Cheese: Organoleptic Considerations1

Journal of Milk and Food Technology ◽

10.4315/0022-2747-38.3.142 ◽

1975 ◽

Vol 38 (3) ◽

pp. 142-145 ◽

Cited By ~ 11

Author(s):

JANE P. JENSEN ◽

G. W. REINBOLD ◽

C. J. WASHAM ◽

E. R. VEDAMUTBU

Keyword(s):

Lactic Acid ◽

Fatty Acid ◽

Citric Acid ◽

Free Fatty Acid ◽

Cheddar Cheese ◽

Streptococcus Faecalis ◽

Growth And Survival ◽

Respective Control ◽

Significant Difference

Eight lots of Cheddar cheese were manufactured with two strains each of Streptococcus faecalis and Streptococcus durans and subjected to combinations of two early cooling treatments (air vs. brine cooling) and two curing temperatures (7.2 and 12.8 C). The enterococcus cultures were used as supplemental starters in combination with a commercial lactic culture. These cheeses were analyzed for microbiological growth and survival, proteolysis, lactic acid development, free fatty acid appearance, and citric acid utilization—each being compared with a control cheese made without enterococci. Results were presented in three previous articles. This series is concluded with the results of organoleptic ana1ysis of the cheeses. Cheeses made with S. faecalis were either comparable to or less desirable than their respective control cheeses. Those made with S. durans, however, were in all instances more desirable than their controls. Cheeses cured at 7.2 C were always given the better scores, but there was no statistically significant difference between air- and brine-cooled cheeses.

Download Full-text

Peptide Accumulation and Bitterness in Cheddar Cheese Made Using Single-Strain Lactococcus lactis Starters with Distinct Proteinase Specificities

Journal of Dairy Science ◽

10.3168/jds.s0022-0302(98)75581-x ◽

1998 ◽

Vol 81 (2) ◽

pp. 327-337 ◽

Cited By ~ 72

Author(s):

Jeffery R. Broadbent ◽

Marie Strickland ◽

Bart C. Weimer ◽

Mark E. Johnson ◽

James L. Steele

Keyword(s):

Lactococcus Lactis ◽

Cheddar Cheese ◽

Single Strain

Download Full-text

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.

Download Full-text

An application in cheddar cheese manufacture for a strain of Lactococcus lactis producing a novel broad-spectrum bacteriocin, lacticin 3147.

Applied and Environmental Microbiology ◽

10.1128/aem.62.2.612-619.1996 ◽

1996 ◽

Vol 62 (2) ◽

pp. 612-619 ◽

Cited By ~ 261

Author(s):

M P Ryan ◽

M C Rea ◽

C Hill ◽

R P Ross

Keyword(s):

Lactococcus Lactis ◽

Broad Spectrum ◽

Cheddar Cheese ◽

Lacticin 3147

Download Full-text

Microbiology of Cheddar cheese made with different fat contents using a Lactococcus lactis single-strain starter

Journal of Dairy Science ◽

10.3168/jds.2012-6443 ◽

2013 ◽

Vol 96 (7) ◽

pp. 4212-4222 ◽

Cited By ~ 24

Author(s):

J.R. Broadbent ◽

C. Brighton ◽

D.J. McMahon ◽

N.Y. Farkye ◽

M.E. Johnson ◽

...

Keyword(s):

Lactococcus Lactis ◽

Cheddar Cheese ◽

Single Strain

Download Full-text

Task Distribution between Acetate and Acetoin Pathways To Prolong Growth inLactococcus lactisunder Respiration Conditions

Applied and Environmental Microbiology ◽

10.1128/aem.01005-18 ◽

2018 ◽

Vol 84 (18) ◽

Cited By ~ 3

Author(s):

Bénédicte Cesselin ◽

Christel Garrigues ◽

Martin B. Pedersen ◽

Célia Roussel ◽

Alexandra Gruss ◽

...

Keyword(s):

Lactic Acid ◽

Stationary Phase ◽

Lactococcus Lactis ◽

Time Course ◽

Biomass Yield ◽

Fine Tuning ◽

Ph Homeostasis ◽

Content Type ◽

Growth And Survival ◽

Bacterial Physiology

ABSTRACTLactococcus lactisis the main bacterium used for food fermentation and is a candidate for probiotic development. In addition to fermentation growth, supplementation with heme under aerobic conditions activates a cytochrome oxidase, which promotes respiration metabolism. In contrast to fermentation, in which cells consume energy to produce mainly lactic acid, respiration metabolism dramatically changes energy metabolism, such that massive amounts of acetic acid and acetoin are produced at the expense of lactic acid. Our goal was to investigate the metabolic changes that correlate with significantly improved growth and survival during respiration growth. Using transcriptional time course analyses, mutational analyses, and promoter-reporter fusions, we uncover two main pathways that can explain the robust growth and stability of respiration cultures. First, the acetate pathway contributes to biomass yield in respiration without affecting medium pH. Second, the acetoin pathway allows cells to cope with internal acidification, which directly affects cell density and survival in stationary phase. Our results suggest that manipulation of these pathways will lead to fine-tuning respiration growth, with improved yield and stability.IMPORTANCELactococcus lactisis used in food and biotechnology industries for its capacity to produce lactic acid, aroma, and proteins. This species grows by fermentation or by an aerobic respiration metabolism when heme is added. Whereas fermentation leads mostly to lactic acid production, respiration produces acetate and acetoin. Respiration growth leads to greatly improved bacterial growth and survival. Our study aims at deciphering mechanisms of respiration metabolism that have a major impact on bacterial physiology. Our results showed that two metabolic pathways (acetate and acetoin) are key elements of respiration. The acetate pathway contributes to biomass yield. The acetoin pathway is needed for pH homeostasis, which affects metabolic activities and bacterial viability in stationary phase. This study clarifies key metabolic elements that are required to maintain the growth advantage conferred by respiration metabolism and has potential uses in strain optimization for industrial and biomedical applications.

Download Full-text