Microbiological Study of León Raw Cow-Milk Cheese, a Spanish Craft Variety

The levels of several microbial groups (aerobic mesophilic flora, aerobic psychrotrophic flora, lactic acid bacteria, Micrococcaceae, enterococci, Enterobacteriaceae, and molds and yeasts), and some biochemical parameters were investigated during the manufacture and ripening of four batches of León cow cheese produced from raw milk without the addition of starter cultures. The study of the microbial characteristics of this cheese constitutes the first step towards the establishment of a starter culture which would allow the making of a product both more uniform and safer from the point of view of health. The total microbial counts were high throughout the elaboration and ripening. Almost all the microbial groups reached their maximum counts in curd and afterwards dropped throughout the ripening process. The greatest drop was shown by Enterobacteriaceae, which had disappeared after 3 months of ripening. Lactic acid bacteria were the major microbial group, reaching counts similar to the total aerobic mesophilic flora at all sampling points. Lactococcus lactis subsp. lactis dominated in milk (62.5% of the isolates obtained in de Man-Rogosa-Sharpe (MRS) agar at this sampling point), curd (82.5% of the isolates obtained at this sampling point) and one-week-old cheese (85% of isolates obtained at this sampling point), while Lactobacillus casei subsp. casei was the most predominant species in eight-week-old cheese (55% of isolates obtained at this sampling point) and twelve-week-old cheese (47.5% of isolates obtained at this sampling point). According to our data, a starter suitable for the production of León cow cheese would be made up of these two species. Some species of Leuconostoc or enterococci could also be added to this starter with the aim of improving the organoleptic characteristics of the final product or to emphasize the characteristics of this variety.

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Antilisterial activity of lactic acid bacteria against Listeria monocytogenes strains originating from different sources

Czech Journal of Food Sciences ◽

10.17221/475/2012-cjfs ◽

2014 ◽

Vol 32 (No. 2) ◽

pp. 145-151 ◽

Cited By ~ 4

Author(s):

I. Složilová ◽

S. Purkrtová ◽

M. Kosová ◽

M. Mihulová ◽

E. Šviráková ◽

...

Keyword(s):

Lactic Acid ◽

Listeria Monocytogenes ◽

Lactic Acid Bacteria ◽

Starter Culture ◽

Raw Milk ◽

Starter Cultures ◽

Cow Milk ◽

Live Cells ◽

Dairy Equipment ◽

Different Sources

Eight individual bacteriocin-producing lactic acid bacteria (LAB) strains and three bacteriocin-non-producing cheese starter cultures were evaluated for their ability to inhibit the growth of six Listeria monocytogenes strains, originating from the guinea-pig lymph nodes, raw cow milk, and manufacturing dairy equipment. Results showed that either live cells or cell-free neutralised supernatant (CFNS) and/or heated CFNS of six individual LAB strains (Lcc. lactis subsp. lactis CCDM 416 and NIZO R5, Lbc. plantarum HV 11 and DC 1246, P. acidilactici HV 12, and Ent. mundtii CCM 1282) and one starter culture (DELVO-ADD<sup>®</sup> 100-X DSF) were effective in the suppression of at least one listeria strain. Neither any individual LAB strain nor starter culture was antagonistic toward all studied L. monocytogenes strains, indicating diverse sensitivity/resistance among L. monocytogenes strains to antimicrobial compounds of LAB. The significant susceptibility of listerias isolated from raw milk and dairy equipment together with the strong antilisterial activity of DELVO-ADD<sup>® </sup>100-X DSF could be applied in dairy technology, where commonly used starter cultures could play both the biopreservative and fermentation role.  

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Newly isolated lactic acid bacteria from silage targeting biofilms of foodborne pathogens during milk fermentation

BMC Microbiology ◽

10.1186/s12866-019-1618-0 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 7

Author(s):

Elizaveta Gavrilova ◽

Elizaveta Anisimova ◽

Alsu Gabdelkhadieva ◽

Elena Nikitina ◽

Adel Vafina ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Foodborne Pathogens ◽

Pathogenic Bacteria ◽

Starter Culture ◽

Raw Milk ◽

Raw Material ◽

Plant Materials ◽

Organoleptic Characteristics ◽

Milk Fermentation

Abstract Background Raw milk, meat and plant materials are subjected to high risks of contamination by various pathogenic bacteria and thus their growth prevention is a great challenge in the food industry. Food fermentation by lactic acid bacteria (LAB) besides changing its organoleptic characteristics also helps to eliminate unfavorable microflora and represses growth of pathogens. To the date only few LABs has been reported to exhibit activity against bacteria embedded in the biofilms characterized by extreme resistance to antimicrobials, high exchange rate with resistance genes and represent high risk factor for foodborne disease development. Results Six novel LAB strains isolated from the clover silage exhibited pronounced antibacterial activity against biofilm embedded pathogens. We show explicitly that these strains demonstrate high acidification rate, completely repress the growth of E. coli, S. aureus and to a lesser extent P. aeruginosa as well as exhibit appropriate probiotic and milk-fermenting properties. Moreover, in contrast to the approved probiotic strain Lactobacillus plantarum 8PA3, the new isolates were able to efficiently eradicate preformed biofilms of these pathogens and prevent bacterial spreading originating from the biofilm. We suggest these strains as potential additives to the pre-cultures of conventional LAB strains as efficient tools targeting foodborne pathogens in order to prevent food contamination from either seeded raw material or biofilm-fouled equipment. Conclusions The AG10 strain identified as L. plantarum demonstrate attractive probiotic and milk fermentation properties as well as high resistance to simulated gastric conditions thus appearing perspective as a starter culture for the prevention of bacterial contamination originating from fouled equipment during milk fermentation.

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Effect of somatic cells count of raw caw milk on the fermentation process and quality of ayran

Food Science and Applied Biotechnology ◽

10.30721/fsab2020.v3.i1.73 ◽

2020 ◽

Vol 3 (1) ◽

pp. 1

Author(s):

Ivelina Ivanova ◽

Ahmet Uzatici ◽

Ertugrul Bilgueu ◽

Tatyana Balabanova ◽

Galin Ivanov

Keyword(s):

Lactic Acid ◽

Milk Fat ◽

Fermentation Process ◽

Scientific Information ◽

Starter Culture ◽

Somatic Cells ◽

Raw Milk ◽

Quality Characteristics ◽

Cow Milk ◽

Organoleptic Characteristics

The present study aimed to provide scientific information for the effect of somatic cells count (SCC) of raw cow milk on the fermentation process and quality characteristics of ayran. Test ayran samples were produced from three different batches of cow milk with low (<400,000 cells.cm-3), medium (between 500,000 and 600,000 cells.cm-3) and high (1000,000 cells.cm-3) SCC, respectively. The main physicochemical parameters as pH, total solids, milk fat, protein, lactose, lactic acid content and microbiological parameters as somatic cells count (SCC) and total viable count (TVC) of raw milk and ayran samples were studied. During the first coagulation stages, the higher SCC in the milk seems to have an inhibiting effect on the development of the lactic acid bacteria from the starter culture and on the fermentation process, respectively. Nevertheless, SCC of the raw milk did not have a significant effect on the composition of the ayran. The increase in the SCC values up to 1000,000 cells.cm-3 in the raw cow’s milk affected negatively the organoleptic characteristics of the ayran made from it. Practical applications:The knowledge for the effect of SCC of raw caw milk on the fermentation process allows us to optimize the technology parameters for production of ayran and to improve its quality characteristics. The data from sensory analysis of ayran samples produced by milks with different SCC will provide additional information for the importans of the implementation of the monitoring of somatic cells in raw caw milk quality control.

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Development of biotechnology for gluten-free sourdough bakery products with a new microbial composition

Khleboproducty ◽

10.32462/0235-2508-2020-29-12-59-63 ◽

2020 ◽

Vol 29 (12) ◽

pp. 59-63

Author(s):

O.I. Parakhina ◽

◽

M.N. Lokachuk ◽

L.I. Kuznetsova ◽

E.N. Pavlovskaya ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Starter Culture ◽

Comparative Assessment ◽

Starter Cultures ◽

Bakery Products ◽

Gluten Free ◽

Microbial Composition ◽

Fermentative Activity ◽

Theoretical Foundations

The research was carried out within the framework of the theme of state assignment № 0593–2019–0008 «To develop theoretical foundations for creating composite mixtures for bakery products using physical methods of exposure that ensure homogeneity, stability of mixtures and bioavailability of nutrients, to optimize diets population of Russia». The data on the species belonging of new strains of lactic acid bacteria and yeast isolated from samples of good quality gluten-free starter cultures are presented. A comparative assessment of the antagonistic and acid-forming activity of strains of lactic acid bacteria and the fermentative activity of yeast was carried out. The composition of microbial compositions from selected strains of LAB and yeast was developed. The influence of the starter culture on the new microbial composition on the physicochemical, organoleptic indicators of the bread quality and resistance to mold and ropy-disease was investigated.

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Evaluating the technological properties of lactic acid bacteria in Wagyu cattle milk

Journal of Dairy Research ◽

10.1017/s0022029921000339 ◽

2021 ◽

pp. 1-7

Author(s):

Harutoshi Tsuda ◽

Kana Kodama

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Raw Milk ◽

Starter Cultures ◽

Technological Properties ◽

Mature Milk ◽

16S Rdna Sequence Analysis ◽

Physiological And Biochemical Characteristics ◽

Fermented Dairy Products ◽

Fermented Dairy

Abstract This paper reveals the technological properties of lactic acid bacteria isolated from raw milk (colostrum and mature milk) of Wagyu cattle raised in Okayama Prefecture, Japan. Isolates were identified based on their physiological and biochemical characteristics as well as 16S rDNA sequence analysis. Streptococcus lutetiensis and Lactobacillus plantarum showed high acid and diacetyl-acetoin production in milk after 24 h of incubation at 40 and 30°C, respectively. These strains are thought to have potential for use as starter cultures and adjunct cultures for fermented dairy products.

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Lactic Acid Bacteria in Cheddar Cheese Made with Sodium Chloride, Potassium Chloride or Mixtures of the Two Salts

Journal of Food Protection ◽

10.4315/0362-028x-58.1.62 ◽

1995 ◽

Vol 58 (1) ◽

pp. 62-69 ◽

Cited By ~ 14

Author(s):

K. ANJAN REDDY ◽

ELMER H. MARTH

Keyword(s):

Lactic Acid ◽

Sodium Chloride ◽

Lactic Acid Bacteria ◽

Potassium Chloride ◽

Starter Culture ◽

Cheddar Cheese ◽

Starter Cultures ◽

Detectable Effect ◽

Agar Media ◽

Cheese Curd

Three different split lots of Cheddar cheese curd were prepared with added sodium chloride (NaCl) potassium chloride (KCl) or mixtures of NaCl/KCl (2:1 1:1 1:2 and 3:4 all on wt/wt basis) to achieve a final salt concentration of 1.5 or 1.75%. At intervals during ripening at 3±1°C samples were plated with All-Purpose Tween (APT) and Lactobacillus Selection (LBS) agar. Isolates were obtained of bacteria that predominated on the agar media. In the first trial (Lactococcus lactis subsp. lactis plus L. lactis subsp. cremoris served as starter cultures) L. lactis subsp.lactis Lactobacillus casei and other lactobacilli were the predominant bacteria regardless of the salting treatment Received by the cheese. In the second trial (L. lactis subsp. lactis served as the starter culture) unclassified lactococci L. lactis subsp. lactis unclassified lactobacilli and L. casei predominated regardless of the salting treatment given the cheese. In the third trial (L. lactis subsp. cremoris served as the starter culture) unclassified lactococci unclassified lactobacilli L. casei and Pediococcus cerevisiae predominated regardless of the salting treatment applied to the cheese Thus use of KCl to replace some of the NaCl for salting cheese had no detectable effect on the kinds of lactic acid bacteria that developed in ripening Cheddar cheese.

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Production of Nigerian Yoghurt Using Lactic Acid Bacteria as Starter Cultures

Asian Food Science Journal ◽

10.9734/afsj/2020/v16i330173 ◽

2020 ◽

pp. 32-42

Author(s):

S. Aforijiku ◽

S. M. Wakil ◽

A. A. Onilude

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Proximate Composition ◽

Room Temperature ◽

Starter Cultures ◽

Cow Milk ◽

Spontaneous Fermentation ◽

Overall Acceptability ◽

Fermentation Control ◽

Better Than

Aim: This work was carried out to investigate the influence of Lactic Acid Bacteria (LAB) on organoleptic quality and proximate composition of yoghurt, and viability of starter cultures in yoghurt. Methods: The LAB starter cultures were selected based on their ability to produce diacetyl and lactic acid. Results: Lactobacillus caseiN1 produced the highest quantity (2.72 g/L) of diacetyl at 48 hrs of incubation while Pediococcus acidilacticiG1 had the lowest amount (0.50 g/L). The pH of produced yoghurt ranged between 4.40 and 5.58 while the corresponding lactic acid contents ranged between 0.70 and 0.96 g/L. Yoghurt produced with cow milk inoculated with L. PlantarumN24 and L. BrevisN10 had the lowest pH (4.40) at significant level of P≤0.05. Yoghurt with mixed culture of L. PlantarumN24 and L. PlantarumN17 had the highest protein content (5.13%) while spontaneous fermentation (control) produced the least (0.48%). Yoghurt produced from cow milk inoculated with L. PlantarumN24 and L. PlantarumN17 was rated best with overall acceptability (9.0) during first day of storage while the commercial yoghurt (5.8) and spontaneous fermentation (6.8) had least overall acceptability at P≤0.05. Conclusion: Yoghurt samples stored in refrigerator had more viable LAB counts for a period of 21 days while the samples stored at room temperature had a day count except for yoghurt produced with cow milk inoculated with L. plantarumN24 which retained its viability at the second day. The yoghurt produced with selected LAB starters are better than commercial yoghurt in terms of sensory properties, proximate composition, pH and viability.

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Influence of Enterococci and Lactobacilli on Listeria

Czech Journal of Food Sciences ◽

10.17221/676-cjfs ◽

2010 ◽

Vol 27 (Special Issue 2) ◽

pp. 12-17

Author(s):

K. Kučerová ◽

I. Korbová ◽

Š. Horáčková ◽

E. Šviráková ◽

M. Plocková

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Raw Milk ◽

Proteinase K ◽

Cow Milk ◽

Live Cells ◽

Enterococcus Spp ◽

Almost All

A collection of lactic acid bacteria (38 Enterococcus and 41 Lactobacillus strains) was tested for the antilisterial activity against 15 Listeria spp. strains (two L. monocytogenes, one L. ivanovii and 12 L. innocua strains) using agar spot method. Out of all 79 bacteria only six Enterococcus strains (1/3A, 3/3A, 6/4D, 6/1A, 1282 and EN3) exhibited antilisterial activity against almost all used indicator strains, when their live cells were tested. When their cell free neutralised supernatants (CFNS) were tested against four selected indicator strains (L. innocua Ln-03, Ln-06, Ln-10 and L. monocytogenes CCM5576) only two Enterococcus spp. strains were active – E. faecalis 6/1A strain from raw cow milk of minor interest due to the activity of its CFNS only against L. innocua Ln-06 and thermolability of the compound and E. mundtii 1282 strain from goat raw milk with CFNS active against 13 Listeria spp. strains including L. monocytogenes. E. mundtii 1282 strain produced probably a bacteriocin, because it completely lost the activity after treatment CFNS with proteinase K.

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The Effects of Cultivating Lactic Starter Cultures with Bacteriocin-Producing Lactic Acid Bacteria

Journal of Food Protection ◽

10.4315/0362-028x-64.1.81 ◽

2001 ◽

Vol 64 (1) ◽

pp. 81-86 ◽

Cited By ~ 24

Author(s):

A. OUMER ◽

S. GARDE ◽

P. GAYA ◽

M. MEDINA ◽

M. NUÑEZ

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Starter Culture ◽

Starter Cultures ◽

The Other ◽

Aminopeptidase Activity ◽

Adjunct Cultures ◽

Nisin Z ◽

Bacteriocin Producer ◽

Test Organisms

The effects of bacteriocins produced by six strains of lactic acid bacteria on 9 mesophilic and 11 thermophilic commercial starter cultures were investigated in mixed cultures of commercial starters with bacteriocin-producing strains in milk. The bacteriocins produced by the test organisms were nisin A, nisin Z, lacticin 481, enterocin AS-48, a novel enterocin, and a novel plantaricin. Mesophilic commercial starters were in most cases tolerant of bacteriocins, with only two of the starters being partially inhibited, one by four and the other by two bacteriocins. The aminopeptidase activities of mesophilic starters were generally low, and only one of the combinations of mesophilic starter–bacteriocin producer gave double the aminopeptidase activity of the starter culture without the bacteriocin producer. Thermophilic commercial starters were more sensitive to bacteriocins than mesophilic starters, with six thermophilic starters being partially inhibited by at least one of the bacteriocins. Their aminopeptidase activities were generally higher than those of the mesophilic starters. The aminopeptidase activities of seven thermophilic starters were increased in the presence of bacteriocins, by factors of up to 9.0 as compared with the corresponding starter cultures alone. Bacteriocin-producing strains may be used as adjunct cultures to mesophilic starters for the inhibition of pathogens in soft and semihard cheeses, because mesophilic starters are rather tolerant of bacteriocins. Bacteriocin producers may also be used as adjunct cultures to thermophilic starters of high aminopeptidase activity, more sensitive to lysis by bacteriocins than mesophilic starters, for the acceleration of ripening in semihard and hard cheeses.

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Importância das Bactérias Ácido Láticas e não Starter (NSLAB) na Tecnologia de Produção dos Derivados Lácteos

Ensaios e Ciência C Biológicas Agrárias e da Saúde ◽

10.17921/1415-6938.2020v24n4p348-352 ◽

2020 ◽

Vol 24 (4) ◽

pp. 348-352

Author(s):

Maria Tereza Pereira ◽

Elsa Helena Walter de Santana ◽

Joice Sifuentes dos Santos

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Lactococcus Lactis ◽

Lactobacillus Casei ◽

Streptococcus Thermophilus ◽

Raw Milk ◽

Fermented Milk ◽

Starter Cultures ◽

Bacillus Spp ◽

Lactobacillus Spp

Produtos lácteos fermentados contêm bactérias ácido lácticas (BAL), naturalmente presentes ou adicionadas na matriz láctea como culturas iniciadoras (starters), contribuindo com aroma, textura, valor nutricional e segurança microbiológica. Lactobacillus spp., Streptococcus spp., Lactococcus spp. e Leuconostoc spp. são utilizados como culturas starters em laticínios. As BAL podem ser classificadas em mesofílicas (ex Lactococcus lactis) e termofílicas (ex Streptococcus thermophilus), e de acordo com seus metabólitos de fermentação em homofermentativas (ácido lático) e heterofermentativas (ácido lático, dióxido de carbono, diacetil e outros compostos flavorizantes). Entre as BAL há um grupo de bactérias lácticas que não fazem parte da cultura láctica (non starter lactic acid bacteria - NSLAB), que são oriundas do leite cru, do ambiente de ordenha ou da indústria formando biofilmes. As NSLAB são representadas por espécies heterofermentativas de lactobacilos mesofílicos como Lactobacillus casei spp., L. paracasei spp., L. rhamnosus spp. e L. plantarum spp., e ainda por Pediococcus spp., Leuconostoc spp. e Micrococcus spp. NSLAB termoduricas como Bacillus spp. também são relatadas. As NSLAB em queijos podem ajudar a desenvolver sabor e aroma, porém também são associadas aos defeitos em queijos e leites fermentados. Problemas como odores estranhos, sabor amargo ou muito ácido, perda de viscosidade, perda de coloração, estufamento e formação de gás são associados com a presença e contaminação por NSLAB. Assim, as BAL são importantes micro-organismos na indústria láctea, garantindo sabores e aromas aos derivados. Já a presença de NSLAB podem ser associados com defeitos em queijos e leites fermentados, sendo um problema na indústria beneficiadora. Palavras-chave: Característica Sensorial. Leites Fermentados. Queijo. Textura. Abstract Fermented dairy products contain acid bacteria (BAL) naturally present or added to the dairy matrix as starter cultures (starters), contributing to aroma, texture, nutritional value and microbiological safety. Lactobacillus spp., Streptococcus spp., Lactococcus spp. and Leuconostoc spp. are used as starter dairy crops. As BAL it can be classified as mesophilic (ex: Lactococcus lactis) and thermophilic (ex: Streptococcus thermophilus), and agree with its fermentation metabolites in homofermentative (lactic acid) and heterofermentative (lactic acid, carbon dioxide, diacetyl and other flavorings). Among the BAL, there is a group of lactic bacteria that are not part of the dairy culture (non-initiating lactic acid bacteria - NSLAB) that originate from raw milk, the milking environment or the biofilm-forming industry. NSLAB is represented by heterofermentative species of mesophilic lactobacilli such as Lactobacillus casei spp., L. paracasei spp., L. rhamnosus spp. and L. plantarum spp., and also by Pediococcus spp., Leuconostoc spp. and Micrococcus spp. Termoduric NSLAB such as Bacillus spp. are also related. NSLAB in cheeses may help develop flavor and aroma, and they are also associated with defects in fermented cheeses and milks. Problems such as strange odors, bitter or very acidic taste, loss of viscosity, loss of color, establishment and gas training are associated with the presence and contamination by NSLAB. Thus, BALs are important microorganisms in the dairy industry, contributing to the dairy flavors and aromas. The presence of NSLAB, on the other hand, can be associated with defects in fermented milk and cheese, being a problem in the processing industry. Keywords: Cheese. Fermented Milk. Sensory Characteristic. Texture.

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