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1
Hosoda, M., H. Hashimoto, H. Morita, M. Chiba e A. Hosono. "Studies on antimutagenic effect of milk cultured with lactic acid bacteria on the Trp-P2-induced mutagenicity to TA98 strain of Salmonella typhimurium". Journal of Dairy Research 59, n. 4 (novembre 1992): 543–49. http://dx.doi.org/10.1017/s0022029900027217.
Testo completoAbstract (sommario):
SummaryThe inhibitory effects of cultured milk using 76 strains of lactic acid bacteria isolated from milk products were investigated on the mutagenicity of 3-amino-1-methyl-5H-pyrido[4,3−b]indole (Trp-P2), a tryptophan pyrolysate for Salmonella typhimurium TA98. Each cultured milk sample displayed its characteristic antimutagenic effect against the mutagenicity of Trp-P2. The milk cultured with Lactobacillus acidophilus LA106 (LA2) showed the highest inhibition of 82·1% among the strains used. Milk samples cultured with Lactococcus lactis subsp. lactis, L11103 (10−3) and L11102 (KM) also exhibited higher inhibition percentages.
2
ITOH, Takatoshi. "Functional Benefits from Lactic Acid Bacteria used in Cultured Milk". Nihon Chikusan Gakkaiho 63, n. 12 (1992): 1276–89. http://dx.doi.org/10.2508/chikusan.63.1276.
Testo completo
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Hudecová, A., Ľ. Valík e D. Liptáková. "Quantification of Geotrichum candidum growth in co-culture with lactic acid bacteria". Czech Journal of Food Sciences 27, Special Issue 2 (3 gennaio 2010): 18–27. http://dx.doi.org/10.17221/205/2009-cjfs.
Testo completoAbstract (sommario):
The growth dynamics of filamentous fungus G. candidum was studied during the co-cultivation with the commercial lactic acid bacteria (LAB) culture Fresco. The experiments were carried out in milk and on the surface of a milk agar at the temperature ranging from 5 to 37°C. Ratkowsky model was used to describe the relationships of the fungal growth rate to the temperature during both, single and co-cultivation with LAB in milk. Simultaneous growth of LAB affected significantly the growth rate of the filamentous fungus. The growth of G. candidum was in average 39% slower in the co-culture than in the single cultivation. LAB pre-inoculated and growing in the solid medium did not show any significant inhibitory effect on the surface growth of G. candidum at all tested temperature. The precise data describing the growth of this cheese yeast-like fungus, G. candidum, may fill a gap in the field of quantitative food mycology and may be used for predicting its behavior in real conditions.
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BİÇER, Yusuf, e Gürkan UÇAR. "Lactic acid bacteria and identification with PCR-DGGE". International Journal of Biological Research 5, n. 1 (5 aprile 2017): 22. http://dx.doi.org/10.14419/ijbr.v5i1.7392.
Testo completoAbstract (sommario):
Lactic acid bacteria (LAB) are an important group in the industrially using microorganisms. The first pure cultures of bacteria was "Bacterium lactis" (probably Lactococcus lactis), obtained in 1873 by J. Lister. LAB are Gram-positive, non motile, non spore-forming, except Sporolactobacillus inulinus, catalase negative, microaerophilic or anaerobic microorganisms. LAB can be found in milk and dairy products, plants and human and animal intestinal mucosa. LAB have low Guanine and Cytosine (G+C) ratio.The industrial applications of lactic acid bacteria is considered, it is emphasized that reliable typing methods in strain levels are getting important about both study on cultures used in functional foods and determining the performance of LAB starter cultures. Denaturing Gradient Gel Electrophoresis (DGGE) is the most common technique in molecular fingerprinting culture-independent techniques. The technique is based on the separation of the same length but having different sequences of the Polymerase Chain Reaction (PCR) products.
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Tasturganova, Elmira, Fatima Dikhanbaeva, Alexandr Prosekov, Gulzat Zhunusova, Bagila Dzhetpisbaeva e Ainur Matibaeva. "Research of Fatty Acid Composition of Samples of Bio-Drink Made of Camel Milk". Current Research in Nutrition and Food Science Journal 6, n. 2 (25 agosto 2018): 491–99. http://dx.doi.org/10.12944/crnfsj.6.2.23.
Testo completoAbstract (sommario):
Adequate nutrition is the most important determinant of the human health. Taking into account this factor, development of the technology for special purpose dairy products based on camel milk using probiotic starter cultures that will have the ability to destroy toxic metabolites, produce amino acids, volatile fatty acids and synthesize vitamins is the urgent task. In connection with the objective set, we have developed 4 samples of dairy products based on camel milk, and examined fatty acid composition thereof on the basis of the Scientific Research Institute of Biotechnology FSBEI HE Kemerovo Institute of Food Science and Technology (University). In the scientific article four samples of the product based on milk are considered. The first sample of the fermented Bacterial leaven of thermophilic lactic acid lactococcus, propionic acid and acetic acid bacteria and Bacterial leaven of thermophilic lactic acid sticks АНВ. The second sample was prepared using Bacterial leaven of thermophilic lactic acid sticks АВ and Bacterial leaven of thermophilic lactic acid lactococcus, propionic acid and acetic acid bacteria. The third sample fermented Bacterial leaven of thermophilic lactic acid sticks Бн and Bacterial leaven of thermophilic lactic acid sticks АНВ. The fourth sample prepared with the addition of Bacterial leaven of thermophilic lactic acid sticks АВ and Bacterial leaven of thermophilic lactic acid sticks Бн. Using the method of chemical ionization with positive and negative ions recording on a chromatographic mass-spectrometer, we determined the content of saturated and unsaturated fatty acids in the samples studied. High content of these acids was found in samples № 1 and № 2. In samples 3 and 4, the acid content was low.
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Složilová, I., S. Purkrtová, M. Kosová, M. Mihulová, E. Šviráková e K. Demnerová. "Antilisterial activity of lactic acid bacteria against Listeria monocytogenes strains originating from different sources". Czech Journal of Food Sciences 32, No. 2 (22 aprile 2014): 145–51. http://dx.doi.org/10.17221/475/2012-cjfs.
Testo completoAbstract (sommario):
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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Levasseur-Garcia, Cecile, Christel Couderc e Helene Tormo. "Discrimination of lactic acid bacteria Enterococcus and Lactococcus by infrared spectroscopy and multivariate techniques". Journal of Near Infrared Spectroscopy 25, n. 4 (30 luglio 2017): 231–41. http://dx.doi.org/10.1177/0967033517719383.
Testo completoAbstract (sommario):
Raw milk is often described as a major source of lactic acid bacteria for indigenous lactic starter. These indigenous starters contribute to the sensorial quality of cheese. Raw milk, rich in Lactoccocus lactis may therefore be very interesting for the cheese making. Currently, the most commonly used methods to differentiate lactic acid bacteria, and particularly the closely related phenotypes Lactococcus and Enterococcus, are based on DNA sequencing, but the cost and time required for these analytical methods hinder their use for rapid screening of raw material. The present study therefore proposes a simple alternative method to identify and discriminate against Lactococcus and Enterococcus, at the genus, but also at the species level, that is based on collecting near infrared spectra directly from bacterial colonies in Petri dishes. The infrared spectra of 280 strains of Lactococcus and Enterococcus cultured on solid media were collected by using a spectrometer with a wavelength range of 908 to 1684 nm and a remote probe. The best Classification And Regression Trees models for genus and species discrimination gave an excellent classification rate of 87% on an external validation set (30 strains). Loading line plots, with prominent bands at 900–960 and 1270–1390 nm, confirmed that the source of variation was due to changes in the polysaccharides.
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FOUCAUD, CATHERINE, SYLVIANE FURLAN, PASCALE BELLENGIER, VINCENT JUILLARD e JEAN RICHARD. "Nutritional value of the non-protein N that accumulates during growth of proteinase-positive strains of Lactococcus lactis in milk for dairy lactococcal and leuconostoc isolates". Journal of Dairy Research 65, n. 3 (agosto 1998): 491–501. http://dx.doi.org/10.1017/s002202999800288x.
Testo completoAbstract (sommario):
To estimate the suitability of cultured milk for the subsequent growth of dairy lactic acid bacteria in cheese manufacturing, control milk was first cultured until the end of the exponential phase with one of four proteolytic (Prt+) strains of Lactococcus lactis differing in their proteolytic enzymes, and pasteurized after readjusting the pH to its initial value. Nineteen non-proteolytic (Prt−) strains of Lc. lactis and nine Leuconostoc mesenteroides strains of dairy origin were then grown in the precultured milk until the stationary phase and their growth was compared with that in control milk. Despite the accumulation of non-protein N (NPN) during preculture, the growth of most Prt− strains of Lc. lactis in precultured milk was either reduced or unchanged whereas that of Ln. mesenteroides strains was unchanged or slightly stimulated. This reduction in growth was reversed by adding an NPN source to precultured milk, indicating that it was due to the exhaustion of assimilable NPN in precultured milk. Thus, preculturing milk with Prt+ strains of Lc. lactis could not be recommended for promoting the subsequent growth of starter cultures in cheese manufacturing.
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PITT, WAYNE M., TERENCE J. HARDEN e RON R. HULL. "Behavior of Listeria monocytogenes in Pasteurized Milk during Fermentation with Lactic Acid Bacteria". Journal of Food Protection 63, n. 7 (1 luglio 2000): 916–20. http://dx.doi.org/10.4315/0362-028x-63.7.916.
Testo completoAbstract (sommario):
The behavior of Listeria monocytogenes in pasteurized milk during fermentation with starter and nonstarter lactic acid bacteria was investigated. Pasteurized milk was co-inoculated with approximately 104 CFU/ml of L. monocytogenes and 106 CFU/ml of Lactococcus lactis, Lactococcus cremoris, Lactobacillus plantarum, Lactobacillus bulgaricus, or Streptococcus thermophilus. Inoculated milks were incubated at 30°C or 37°C for 24 to 72 h. Listeria monocytogenes survived and also grew to some extent during incubation in the presence of all starter cultures; however, inhibition ranged from 83 to 100% based on maximum cell populations. During incubation with L. bulgaricus and L. plantarum, L. monocytogenes was completely inactivated after 20 h and 64 h of incubation at 37°C and 30°C, respectively. The pH of the fermenting milks declined steadily throughout the fermentation periods and was approximately 4.2 at the conclusion of the experimental period regardless both of the starter culture and pathogen combination or the temperature of incubation.
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Taye, Yeshambel, Tadesse Degu, Haben Fesseha e Mesfin Mathewos. "Isolation and Identification of Lactic Acid Bacteria from Cow Milk and Milk Products". Scientific World Journal 2021 (10 agosto 2021): 1–6. http://dx.doi.org/10.1155/2021/4697445.
Testo completoAbstract (sommario):
Lactic acid bacteria (LAB) have long been consumed by people in several fermented foods such as dairy products. A study was conducted on lactating dairy cows to isolate and characterize LAB from dairy products found in and around Bahir-Dar city, North Western Ethiopia. Milk and milk products were randomly collected from dairy farms, milk vending shops, individual households, and supermarkets for bacteriological investigations. A total of sixteen samples were taken from different sources and cultured on different selective media: de Man, Rogosa, and Sharpe (MRS) agar for Lactobacillus spp.; M17 agar for Lactococcus spp.; Rogasa SL agar for Streptococci spp.; and MRS supplemented with cysteine (0.5%) for Bifidobacteria spp. Different laboratory techniques were implemented for LAB isolation and identification. A total of 41 bacterial isolates were grouped under five different genera of LAB and Bifidobacteria spp. were identified based on the growth morphology on the selective media, growth at a different temperature, gas production from glucose, carbohydrate fermentation, and other biochemical tests. LAB genera such as Lactobacillus, Lactococcus, Leuconostoc, Pediococcus, Streptococcus, and Bifidobacterium spp. were isolated and identified from raw milk, cheese, and yogurt. Based on the current study, the majority of the LAB (24.38%) was isolated from cheese and yogurt. Among these, Lactobacillus, Lactococcus (21.94%), Streptococcus (19.51%), Leuconostoc (14.64%), Bifidobacteria (12.19%), and Pediococcus (7.31%) spp. were also identified from these products. Furthermore, based on the bacterial load count and different identification methodologies, our study revealed that Lactobacillus spp. were the dominant LAB isolated from milk and milk products. As a result, since there are few studies on the isolation and identification of lactic acid bacteria from dairy products in Ethiopia, more research studies are needed to complete the identification and characterization to species level and their possible role as probiotics.
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Ačai, Pavel, Alžbeta Medved'ová, Tatiana Mančušková e L'ubomír Valík. "Growth prediction of two bacterial populations in co-culture with lactic acid bacteria". Food Science and Technology International 25, n. 8 (7 luglio 2019): 692–700. http://dx.doi.org/10.1177/1082013219860360.
Testo completoAbstract (sommario):
The co-culture growth of Staphylococcus aureus, Escherichia coli and lactic acid bacteria starter culture in milk was quantitatively evaluated and modelled with a set of coupled differential equations originally proposed by Baranyi and Roberts and by Gimenez and Dalgaard (BR–GD model). The lactic acid bacteria starter culture showed the ability to induce an early stationary phase of both E. coli and S. aureus populations at different combination of temperature (ranging from 12 to 37 ℃) and lactic acid bacteria inocula (from approx. 103 to 106 CFU/ml). First, the prediction ability was performed only with parameters estimated from individual growth curves of E. coli, S. aureus and the lactic acid bacteria in milk (Dataset 1, 21 experiments). Subsequently, the model was extended with the average competition coefficients (E-BR–GD model) that represented quantitative relations among the populations. The prediction ability of this model was validated with the second dataset consisting of seven experiments. Results and also their statistical indices (accuracy and bias factors) showed that the E-BR–GD model improved growth prediction of all involved populations. Thus, the total root mean square error decreased from 0.457, 0.840 and 0.322 log CFU/ml (BR–GD model) to 0.290, 0.245 and 0.333 log CFU/ml (E-BR–GD) for S. aureus, E. coli and lactic acid bacteria, respectively. This approach in growth prediction of multiple competing microbial populations can be used in assessment of S. aureus and E. coli exposure from raw milk cheeses consumption and contribute to decision making in prevention of staphylococcal enterotoxin production.
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Zhang, Shuang, e Lan Wei Zhang. "Effect of Exopolysaccharide Producing Lactic Acid Bacterial on the Gelation and Texture Properties of Yogurt". Advanced Materials Research 430-432 (gennaio 2012): 890–93. http://dx.doi.org/10.4028/www.scientific.net/amr.430-432.890.
Testo completoAbstract (sommario):
Lactic acid bacterial play a important role in yogurt texture and gel quality. The performance of lactic acid bacteria starter directly affected the quality of yogurt. Exopolysaccharide (EPS)-producing LAB may improve the texture of fermented milks, depending on the strain. EPS production was found to have a major effect on the texture properties and gelation properties, but varying textures with EPS production, structure and interaction with milk proteins. Yoghurts fermented with EPS-producing cultures showed different mouth thickness and ropiness rheological parameters and varying syneresis and gel firmness. The mechanism that how the metabolic properties of EPS producing lactic acid bacteria affect the texture and gel quality of yogurt is reviewed in the article.
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Slyvka, I. M., O. Y. Tsisaryk, G. V. Dronyk e L. Y. Musiy. "Strains of lactic acid bacteria isolated from traditional Carpathian cheeses". Regulatory Mechanisms in Biosystems 9, n. 1 (21 febbraio 2018): 62–68. http://dx.doi.org/10.15421/021808.
Testo completoAbstract (sommario):
Traditional national fermented products and cheeses are a source for the search for species and strains of lactic acid bacteria (LAB) which are not within the range of bacterial agents used in the dairy industry. Classical and modern genetic-molecular methods are used to identify LAB isolated from such products. The purpose of our work was isolation and identification of LAB from traditional Carpathian cheeses made from ewe's milk and the study of their technological properties. Three samples of cheese were selected for our research – one sample of brine cheese bryndza and one sample of budz (bryndza before salting), produced in the highlands of the Carpathians and one sample of buts, produced in the foothills zone. 106 cultures were isolated from the samples of cheese. Genus and species identification was completed using classical microbiological and molecular genetics methods. Based on the complex of tinctorial, cultural, physiological and biochemical indices, the LAB isolated were assigned to the following genera and species: Lactococcus spp. (26 cultures), including L. lactis (13 cultures) and L. garvieae (13 cultures); Lactobacillus spp. – L. plantarum (31 cultures); Enterococcus spp. – E. faecium (25 cultures); Leuconostoc spp. – L. mesenteroides (24 cultures). These results were confirmed by molecular genetics methods. The largest range of species was found in a sample of bryndza from the Carpathian highlands. The isolated cultures were studied according to technological properties – milk-coagulation activity, acid-forming ability and resistance to different concentrations of kitchen salt. Most strains of L. lactis ssp. lactis, L. plantarum and L. mesenteroides were active acid-forming agents and coagulated milk in 3–9 hours, while L. garvieae and E. faecium coagulated milk after more than 24 hours. More than 80% of cultures showed resistance to 4% of kitchen salt solution, E. faecium was observed to have the highest salt tolerance. The results of RAPD typing showed significant intra-species heterogeneity, which indicates the need for further research on identification of individual strains. In all samples of cheese, L. lactis, L. garvieae, E. faecium were detected, which shows that they are typical representatives within the traditional Carpathian bryndza. Particular attention was paid to E. faecium, as many researchers have indicated probiotic properties of individual strains, as well as the ability to synthesize volatile substances that enrich the flavor bouquet of cheeses. Today strains of E. faecium are involved in the bacterial composition of starter cultures for cheeses.
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CHAMPAGNE, C. P., F. GIRARD e N. MORIN. "Inhibition of the Psychrotrophic Bacteria of Raw Milk by Addition of Lactic Acid Bacteria". Journal of Food Protection 53, n. 5 (1 maggio 1990): 400–403. http://dx.doi.org/10.4315/0362-028x-53.5.400.
Testo completoAbstract (sommario):
Two commercial cultures of lactic acid bacteria (LAB) were added to raw milk in order to inhibit the development of psychrotrophic bacteria. The effects of inoculation level, pH development, media for culture preparation, and milk heat treatment on the inhibitory activity of LAB were studied. Inoculation levels of 2.5 × 106/mL and less of LAB did not significantly reduce psychrotrophic growth. Maximum inoculation level of LAB studied was 25 × 106/mL and this reduced psychrotrophic development by a factor of 10; however, milk pH was reduced to 6.54 over 48 h of incubation at 7°C with this inoculation level. This acidification was not responsible for the inhibitory activity of LAB on psychrotrophs. The LAB were more effective when psychrotroph populations had high multiplication rates. Initial populations of Pseudomonas putida in pasteurized milk did not influence the activity of the LAB. Pseudomonas putida grew faster in sterile milk than in pasteurized milk, but average inhibition rates of LAB were similar in both media.
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Кригер, Ольга, Olga Kriger, Светлана Носкова e Svetlana Noskova. "Properties of Lactic Acid Microorganisms: Long-Term Preservation Methods". Food Processing: Techniques and Technology 48, n. 4 (13 febbraio 2019): 30–38. http://dx.doi.org/10.21603/2074-9414-2018-4-30-38.
Testo completoAbstract (sommario):
Among the relevant studies on lactic acid bacteria there are projects devoted to the multienzyme complexes of starter cultures, new competitive bacterial concentrates and their use in fermented functional milk products. In fermented milk production, the process of albuminolysis has a significant impact on the consistency, taste, and smell of the product. Therefore, lactic acid bacteria with high proteolytic properties are of the greatest interest for fermented milk industry. The present research features long- term methods for preservation of the properties of lactic acid microorganisms. The experiment defined the regime parameters of combined starter lyophilisation. The results prove that fermented milk production requires high-quality starter strains. The authors developed a long-term method for preservation of properties of particular strains of lactic acid microorganisms. The method presupposes freeze-drying with the following parameters: freezing temperature – minus 25°C in a protective 5%-glycerol medium (90 minutes); the drying temperature – 30°C (6 hours); refrigerating load – 5.45 kW/m²; residual pressure – 0.6‒0.8 kPa, bed depth – 2 mm. The authors also developed the necessary documentation (No. 9225-096-02054145-2013), procedures, and formula of the fermented milk product with a combined direct application starter.
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REINHEIMER, JORGE A., ANA G. BINETTI, ANDREA QUIBRONI, NANCI B. BAILO, AMELIA C. RUBIOLO e GIORGIO GIRAFFA. "Natural Milk Cultures for the Production of Argentinian Cheeses". Journal of Food Protection 60, n. 1 (1 gennaio 1997): 59–63. http://dx.doi.org/10.4315/0362-028x-60.1.59.
Testo completoAbstract (sommario):
Samples (32) of natural milk cultures used in the Santa Fe, Argentina, area for soft and semihard cheese production were examined. The microbial composition (including lactic acid microflora characterization) and technological parameters (acidifying and proteolytic activities) were evaluated. The cultures contained mainly thermophilic lactic acid bacteria, identified as Streptococcus salivarius subsp. thermophilus (96.8% of the total strains) and Enterococcus spp. The strains showed a low proteolytic activity. The isolates of S. salivarius subsp. thermophilus exhibited a widespread phage resistance. The nonlactic microflora comprised coliforms, yeasts, spore-forming bacteria and lactate fermentative bacteria. The samples showed an acidity level from 0.38 to 0.69% lactic acid (pH from 4.25 to 5.75). The acidifying activity was optimal at 45°C. The advantages and disadvantages of the employment of natural milk starters are discussed.
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Matejčeková, Zuzana, Elena Dujmić, Denisa Liptáková e Ľubomír Valík. "Modeling of lactic acid fermentation of soy formulation with Lactobacillus plantarum HM1". Food Science and Technology International 25, n. 2 (4 ottobre 2018): 141–49. http://dx.doi.org/10.1177/1082013218803257.
Testo completoAbstract (sommario):
Lactic acid bacteria alone or with special adjunct probiotic strains are inevitable for the preparation of various specific functional foods. Moreover, because of their growth and metabolism, the final products are preserved for a certain time. Thus, growth dynamics of the lactic acid bacteria of the Fresco DVS 1010 culture ( Lactococcus lactis spp. lactis, Lactococcus lactis spp. cremoris, Streptococcus salivarius spp. thermophilus) during liquid-state fermentation of soya mashes and pH values within the process were analyzed in this study. Although milk is the most typical growth medium for the lactic acid bacteria, presumable viable counts of Fresco culture reached levels 109 CFU ml−1 after 8 h, representing 2–3 log increase in comparison to initial state (specific growth rates ranged from 1.06 to 1.64 h−1). After 21 days of storage period, the pH levels in the products were reduced to 4.50–4.70, representing a decrease of about 1.5–1.7 units. All prepared soybean products contained detectable amounts of raffinose-series oligosaccharides (0.25–0.68 g per 100 g) that were reduced in average by about 30.5% during period of 21 days.
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SCHAACK, MICHELLE M., e ELMER H. MARTH. "Behavior of Listeria monocytogenes in Skim Milk during Fermentation with Mesophilic Lactic Starter Cultures". Journal of Food Protection 51, n. 8 (1 agosto 1988): 600–606. http://dx.doi.org/10.4315/0362-028x-51.8.600.
Testo completoAbstract (sommario):
The ability of Listeria monocytogenes to grow and compete with mesophilic lactic acid bacteria was examined. Autoclaved skim milk was inoculated with 103 cells of L. monocytogenes (strain V7 or Ohio)/ml, and with 5.0, 1.0, 0.5 or 0.1% of a milk culture of either Streptococcus cremoris or Streptococcus lactis. Inoculated milks were fermented for 15 h at 21 or 30°C, followed by refrigeration at 4°C. Samples were plated on McBride Listeria Agar to enumerate L. monocytogenes and on either APT Agar or plate count agar to enumerate lactic acid bacteria. L. monocytogenes survived in all fermentations, and commonly also grew to some extent. Incubation at 30°C with 5% S. lactis as inoculum appeared to be the most inhibitory combination for strain V7, causing 100% inhibition in growth based on maximum population attained. S. cremoris at the 5.0% and 0.1% inoculum levels, was slightly less inhibitory to L. monocytogenes at 37°C, but it was slightly more inhibitory to L. monocytogenes at the 1.0% inoculum level than was S. lactis. In general, S. lactis reduced the pH of fermented milks more than did S. cremoris. The population of L. monocytogenes began to decrease before 15 h in only one test combination, which was use of a 5.0% inoculum of S. cremoris and 30°C incubation. In most instances, growth of the pathogen appeared to be completely inhibited when the pH dropped below 4.75.
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Morandi, Stefano, Tiziana Silvetti, Alberto Tamburini e Milena Brasca. "Changes in oxidation-reduction potential during milk fermentation by wild lactic acid bacteria". Journal of Dairy Research 83, n. 3 (agosto 2016): 387–94. http://dx.doi.org/10.1017/s0022029916000339.
Testo completoAbstract (sommario):
Oxidation-reduction potential (Eh) is a fundamental physicochemical property of lactic acid bacteria that determines the microenvironment during the cheese manufacture and ripening. For this reason the Eh is of growing interest in dairy research and the dairy industry. The objective of the study was to perform a comprehensive study on the reduction activity of wild lactic acid bacteria strains collected in different periods (from 1960 to 2012) from Italian dairy products. A total of 709 strains belonging to Lactococcus lactis, Enterococcus durans, E. faecium, E. faecalis and Streptococcus thermophilus species were studied for their reduction activity in milk. Kinetics of milk reduction were characterised by the minimum redox potential (Eh7) and time of reaching Eh7 (tmin), the maximum difference between two measures (Δmax) and the time at which these maximum differences occurred (t*). Broad diversity in kinetic parameters was observed at both species and strain levels. E. faecalis and L. lactis resulted to be the most reducing species, while S. thermophilus was characterised by the lowest reducing power while the greatest heterogeneity was pointed out among E. durans and E. faecium strains. Considering the period of collection (1960–2012) we observed that the more recently isolated strains generally showed less reducing activity. This trend was particularly evident for the species E. durans, E. faecium and L. lactis while an opposite trend was observed in E. faecalis species. Data reported in this research provide new information for a deeper understanding of redox potential changes during milk fermentation due to bacterial growth. Gain knowledge of the redox potential of the LAB cultures could allow a better control and standardisation of cheesemaking process.
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Coppola, Salvatore, Vincenzina Fusco, Rosamaria Andolfi, Maria Aponte, Giuseppe Blaiotta, Danilo Ercolini e Giancarlo Moschetti. "Evaluation of microbial diversity during the manufacture of Fior di Latte di Agerola, a traditional raw milk pasta-filata cheese of the Naples area". Journal of Dairy Research 73, n. 3 (29 marzo 2006): 264–72. http://dx.doi.org/10.1017/s0022029906001804.
Testo completoAbstract (sommario):
Microbial diversity of the raw milk for the production of Fior di Latte di Agerola and its changes during cheesemaking were studied. Viable counts showed that at the end of curd ripening, loads of lactic acid bacteria, both mesophilic and thermophilic rods and cocci, higher than those commonly evidenced in similar cheeses produced by using natural or commercial starters, were detected. Identification of 272 isolates, supported by molecular diagnostic aids, evidenced representative cultures of a high number of bacterial taxa of interest as participating in the process, although most of the isolates belonged to Lactococcus lactis and Lactobacillus helveticus species. RAPD-PCR and REA-PFGE biotyping were performed for the isolates of the above species and it was shown that most of the strains isolated from the raw milk occurred during the whole cheesemaking process, and an active role of these strains in the fermentation was supposed. The results offer further proof of the importance of the raw milk as source of technologically interesting strains of lactic acid bacteria capable of driving the fermentation of traditional cheeses.
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Ahlberg, S., P. Kärki, M. Kolmonen, H. Korhonen e V. Joutsjoki. "Aflatoxin M1 binding by lactic acid bacteria in milk". World Mycotoxin Journal 12, n. 4 (4 dicembre 2019): 379–86. http://dx.doi.org/10.3920/wmj2019.2461.
Testo completoAbstract (sommario):
This research focused on biocontrol solution to increase food safety through studying lactic acid bacteria (LAB) which can bind aflatoxins in milk. Aflatoxins are toxic contaminants found in feeds and foods. In milk aflatoxin is found in metabolised form, aflatoxin M1 (AFM1). Three indigenous LAB Lactobacillus strains and one Lactococcus strain isolated from Kenyan spontaneously fermented foods were tested for their AFM1 binding abilities in different conditions and after different treatments along with two reference Lactobacillus strains. Binding of AFM1 in different concentrations was examined with unconcentrated, concentrated, heat treated and concentrated heat-treated LAB cultures. Observed binding of AFM1 by LAB varied between 11 to 100%, being approximately at the level of 40% throughout the analysis sets. The results of this study suggest that the aflatoxin binding ability by LAB strain is not strongly strain specific and depends on many external and condition variables. Also, the methods used in determination of aflatoxin binding warrant critical evaluation.
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Câmara, SP, A. Dapkevicius, C. Riquelme, RB Elias, CCG Silva, FX Malcata e MLNE Dapkevicius. "Potential of lactic acid bacteria from Pico cheese for starter culture development". Food Science and Technology International 25, n. 4 (15 gennaio 2019): 303–17. http://dx.doi.org/10.1177/1082013218823129.
Testo completoAbstract (sommario):
Autochthonous lactic acid bacteria may provide a means of promoting the quality and safety of traditional fermented food products, in particular, artisanal cheeses. Pico cheese is an artisanal, dairy specialty of the Azores in risk of disappearing. Efforts to maintain its quality to the requirements of the modern markets are, thus, necessary. Lactic acid bacteria were isolated from artisanal Pico cheese, identified by sequencing of the 16S rRNA gene, and their potential as starter cultures was evaluated by studying their acidification ability, enzymatic activities (caseinolysis, lipolysis and API-ZYM profile), diacetyl and expolysaccharide production, autolysis, antimicrobial activity against Listeria monocytogenes ATCC 7466, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29523, Pseudomonas aeruginosa ATCC 27853 and Clostridium perfringens ATCC 8357, sensory evaluation of odour formation in milk, syneresis and firmness of the curd. Several of the studied lactic acid bacteria isolates showed interesting properties for practical application as starters in artisanal cheese production. The isolates with the highest number of positive traits and, therefore, the most promising for starter development were Lactococcus lactis ssp. lactis L1C21M1, Lactobacillus paracasei L1B1E3, Leuconostoc pseudomesenteroides L1C1E6, Lactobacillus casei L1A1E5 and L1C1E8.
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Terzic-Vidojevic, Amarela, Milica Nikolic, Katarina Veljovic, Maja Tolinacki, M. Busarcevic e L. Topisirovic. "Analysis of the lactic acid bacteria microflora in traditional Caucasus cow's milk cheeses". Archives of Biological Sciences 61, n. 3 (2009): 395–406. http://dx.doi.org/10.2298/abs0903395t.
Testo completoAbstract (sommario):
A total of 157 lactic acid bacteria (LAB) were isolated from three hand-made cheeses taken from different households in the region of the Caucasus Mountains. The cheeses were manufactured from cow's milk without the addition of a starter culture. The isolates of LAB were characterized by subjecting them to phenotypic and genotypic tests. The results of identification of LAB indicate that the examined cheeses contained 10 species, viz., Lactobacillus plantarum, Lactobacillus paraplantarum, Lactobacillus arizonensis, Lactobacillus farciminis, Lactobacillus brevis, Lactococcus lactis subsp. lactis, Leuconostoc mesenteroides subsp. mesenteroides, Leuconostoc pseudomesenteroides, Enterococcus faecium, and Enterococcus faecalis. The strains within the species L. plantarum, L. arizonensis, L. paraplantarum, L. farciminis, and L. pseudomesenteroides showed good proteolytic activity.
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Harnentis, Harnentis, Nurmiati Nurmiati, Yetti Marlida, Frederick Adzitey e Nurul Huda. "γ-Aminobutyric acid production by selected lactic acid bacteria isolate of an Indonesian indigenous fermented buffalo milk (dadih) origin". August-2019 12, n. 8 (agosto 2019): 1352–57. http://dx.doi.org/10.14202/vetworld.2019.1352-1357.
Testo completoAbstract (sommario):
Aim: This study aimed at optimizing γ-aminobutyric acid (GABA) production using lactic acid bacteria (LAB) of an Indonesian indigenous fermented buffalo milk (dadih) origin. This study utilized LAB previously cultured from dadih that has the ability to produce GABA. Materials and Methods: The study started with the identification of selected LAB by 16S rRNA, followed by optimization of GABA production by culture conditions using different initial pH, temperature, glutamate concentration, incubation time, carbon, and nitrogen sources. 16S rRNA polymerase chain reaction and analysis by phylogenetic were used to identify Lactobacillus plantarum (coded as N5) responsible for the production of GABA. Results: GABA production by high-performance liquid chromatography was highest at pH of 5.5, temperature of 36°C, glutamate concentration of 500 mM, and incubation time of 84 h. Peptone and glucose served as the nitrogen and carbon sources, respectively, whereas GABA was produced at optimum fermentation condition of 211.169 mM. Conclusion: Production of GABA by L. plantarum N5 was influenced by initial pH of 5.5, glutamic acid concentration, nitrogen source, glucose as carbon source, and incubation temperature and time. Keywords: fermented buffalo milk, Indonesian indigenous product, lactic acid bacteria, γ-aminobutyric acid.
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Martinovic, Aleksandra, Roger Abrahamsen e Dragojlo Obradovic. "Biochemical activities of selected strains of Lactic Acid Bacteria". Biotehnologija u stocarstvu 22, n. 1-2 (2006): 139–51. http://dx.doi.org/10.2298/bah0602139m.
Testo completoAbstract (sommario):
In this paper the results of the research on biochemical activities of selected strains of Lactic Acid Bacteria, isolated from indigenous fermented milk products of Serbia and Montenegro have been shown. The growth rate of the selected strains has been examined during 24 hrs period of time as well as carbon dioxide production ability, ability of production/degradation of specific sugars, organic acids and rate of production of volatile compounds that are significantly influencing the aroma of the final products. The analyses for determination of synthesis of sugars, organic acids and volatile compounds have been done by automatic direct headspace gas chromatography (HCGC) and high performance liquid chromatography (HPLC). The examined strains have shown significant level of biochemical activities that can introduce them to the group of potential starter cultures for industrial production of different fermented milk products.
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Cruciata, Margherita, Ciro Sannino, Danilo Ercolini, Maria L. Scatassa, Francesca De Filippis, Isabella Mancuso, Antonietta La Storia, Giancarlo Moschetti e Luca Settanni. "Animal Rennets as Sources of Dairy Lactic Acid Bacteria". Applied and Environmental Microbiology 80, n. 7 (17 gennaio 2014): 2050–61. http://dx.doi.org/10.1128/aem.03837-13.
Testo completoAbstract (sommario):
ABSTRACTThe microbial composition of artisan and industrial animal rennet pastes was studied by using both culture-dependent and -independent approaches. Pyrosequencing targeting the 16S rRNA gene allowed to identify 361 operational taxonomic units (OTUs) to the genus/species level. Among lactic acid bacteria (LAB),Streptococcus thermophilusand some lactobacilli, mainlyLactobacillus crispatusandLactobacillus reuteri, were the most abundant species, with differences among the samples. Twelve groups of microorganisms were targeted by viable plate counts revealing a dominance of mesophilic cocci. All rennets were able to acidify ultrahigh-temperature-processed (UHT) milk as shown by pH and total titratable acidity (TTA). Presumptive LAB isolated at the highest dilutions of acidified milks were phenotypically characterized, grouped, differentiated at the strain level by randomly amplified polymorphic DNA (RAPD)-PCR analysis, and subjected to 16S rRNA gene sequencing. Only 18 strains were clearly identified at the species level, asEnterococcus casseliflavus,Enterococcus faecium,Enterococcus faecalis,Enterococcus lactis,Lactobacillus delbrueckii, andStreptococcus thermophilus, while the other strains, all belonging to the genusEnterococcus, could not be allotted into any previously described species. The phylogenetic analysis showed that these strains might represent different unknown species. All strains were evaluated for their dairy technological performances. All isolates produced diacetyl, and 10 of them produced a rapid pH drop in milk, but only 3 isolates were also autolytic. This work showed that animal rennet pastes can be sources of LAB, mainly enterococci, that might contribute to the microbial diversity associated with dairy productions.
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Li, Ci Li, e Chun Ran Han. "Selection of Lactic Acid Bacteria Stains for the Fermentation of Kidney Beans". Advanced Materials Research 183-185 (gennaio 2011): 1254–57. http://dx.doi.org/10.4028/www.scientific.net/amr.183-185.1254.
Testo completoAbstract (sommario):
The fermentative nature of five lactic acid bacteria was studied by using saccharified kidney beans. The production of lactic acid of lactobacillus acidophilus (La) was the one with highest yield and quickest production rate. The optimal mixes cultures was Lactobacillus acidophilus (La) ， Lactobacillus plantarum（Lp）and Bifidobacterium bifidum (Bb). The optimum proportion of species was La:Lp:Bb= 2: 1: 1. Soybean milk can promote the growth of the lactic acid bacteria.
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Utami, Tyas, Amaralda Cindarbhumi, Marcella C. Khuangga, Endang S. Rahayu, Muhammad Nur Cahyanto, Sri Nurfiyani e Eni Zulaichah. "Preparation of Indigenous Lactic Acid Bacteria Starter Cultures for Large Scale Production of Fermented Milk". Digital Press Life Sciences 2 (2020): 00010. http://dx.doi.org/10.29037/digitalpress.22327.
Testo completoAbstract (sommario):
<div>Lactobacillus plantarum Dad 13, an indigenous probiotic was examined its ability to be used as a single starter culture or mixed cultures with Streptococcus thermophilus Dad 11 for milk fermentation. Both cultures were isolated from dadih, a traditional fermented buffalo milk. The purposes of this study were to produce indigenous lactic acid bacteria starter cultures using halal growth medium and evaluate their application on large scale fermented milk production. The halal medium was developed using natural compounds such as sucrose, meat peptone, mung bean sprout extract, tomato extract, and young coconut water. Meat peptone was prepared by hydrolysis of halal meat using crude bromelain. Lactic acid bacteria were grown in the halal growth medium then harvested, frozen and freeze-dried. A single freeze-dried starter culture of L. plantarum Dad 13 and frozen mixed cultures of L. plantarum Dad 13 and S. thermophilus Dad 11 were prepared for production of fermented milk drink and yogurt respectively in industrial scale. The growth of these lactic acid bacteria in halal growth medium increased the viable cell to two log cycles (109 CFU/mL) for L. plantarum Dad 13 and one log cycle for S. thermophilus Dad 11 (108 CFU/mL), respectively. The viable cell of freeze-dried L. plantarum Dad 13 and S. thermophilus Dad 11 were 7.57 x 1010 CFU/g and 6.35 x 109 CFU/g, respectively. The number of viable cells and pH of both fermented milk drink and yogurt products was relatively stable to 107 CFU/mL and 108 CFU/mL, respectively during cold storage for four to six weeks. The sensory characteristics of the products were comparable to the ones using commercial starter cultures. It can be concluded that these indigenous starter cultures can be applied for the production of probiotic fermented milk.</div>
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DE URRAZA, PATRICIO J., ANDREA GÓMEZ-ZAVAGLIA, MARIO E. LOZANO, VICTOR ROMANOWSKI e GRACIELA L. DE ANTONI. "DNA fingerprinting of thermophilic lactic acid bacteria using repetitive sequence-based polymerase chain reaction". Journal of Dairy Research 67, n. 3 (agosto 2000): 381–92. http://dx.doi.org/10.1017/s002202990000426x.
Testo completoAbstract (sommario):
DNA fingerprints of lactic acid bacteria were generated by polymerase chain reaction using a primer based on the repetitive elements found in the genome of Streptococcus pneumoniae (BOX-PCR). The method made it possible to identify 37 isolates from raw milk, industrial starters and yogurt. Differentiation at species, subspecies and strain level was possible for Lactobacillus delbrueckii subsp. lactis, Lb. delbrueckii subsp bulgaricus and Str. thermophilus. BOX-PCR was also applied to studying the strain composition of a starter culture and the direct detection of strains in commercial fermented milk.
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Němečková, I., H. Dragounová, M. Pechačová, J. Rysová e P. Roubal. "Fermentation of vegetable substrates by lactic acid bacteria as a basis of functional foods". Czech Journal of Food Sciences 29, Special Issue (4 gennaio 2012): S42—S48. http://dx.doi.org/10.17221/282/2011-cjfs.
Testo completoAbstract (sommario):
People suffering from lactose intolerance, cow’s milk allergy or phenylketonuria or people on low-protein diet are restricted in the consumption of dairy products. Their consumers’ basket should be variegated and enriched with probiotics. The main task was to evaluate important growth and metabolic characteristics of lactic acid bacteria in rice, natural rice, corn, chickpea and barley. Suspensions of the respective flours in water (8% w/w) were supplemented with glucose (1% w/w), pasteurised and fermented. Suitable combinations of cultures and substrates enable the growth of microorganisms minimally by t 2 decimal orders. This is connected with a specific shape of the acidification curve pH should be higher than 4.5 after 4-h fermentation. The vegetable samples contained lower concentrations of organic acids than milk samples because of their lower contents of the buffering substances. Fermentation did not result in any decrease in the concentration of protein or phenylalanine. Thus, special formulas of foods for people on phenylketonuria diet or low-protein diets should be conceived. Fermentation of vegetable substrates seems to be a prospective technology in functional foods manufacturing.
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MAURIELLO, GIANLUIGI, MARIA APONTE, ROSAMARIA ANDOLFI, GIANCARLO MOSCHETTI e FRANCESCO VILLANI. "Spray-Drying of Bacteriocin-Producing Lactic Acid Bacteria". Journal of Food Protection 62, n. 7 (1 luglio 1999): 773–77. http://dx.doi.org/10.4315/0362-028x-62.7.773.
Testo completoAbstract (sommario):
Cell survival, cellular damage, and antagonistic activity were investigated after spray-drying of four bacteriocin-producing strains of lactic acid bacteria: Lactococcus lactis subsp. lactis 140, isolated from natural whey culture and producing a narrow-inhibitory spectrum bacteriocin); L. lactis subsp. lactis G35, isolated from pizza dough and producing nisin; Lactobacillus curvatus 32Y and Lactobacillus sp. 8Z, isolated from dry sausages. Trials were performed with bacteria suspended in skimmed milk or directly grown in whey. Three air temperatures at the inlet of the drier (160, 180, and 200°C) and three flow rates (10, 13, and 17 ml/min) were assayed. Cell viability and bacteriocin activity of the dried materials were determined immediately after the process and after 5, 15, 30, and 60 days of storage at 4°C. There was no significant difference between the two feeding suspensions in cell survival, always decreasing with the increase of inlet-air temperature. No loss of bacteriocin activity was detected in reconstituted powders, nor was any loss of ability to produce bacteriocin found after drying. Investigations of sensitivity to NaCl revealed only temporary damage to dried bacteria. During storage for 2 months at 4°C, all samples, but mainly the lactococcal strains, displayed a gradual decrease in cell survival. Bacteriocin activity remained at the same level, allowing powders to be considered as effective biopreservatives.
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Alessandria, Valentina, Ilario Ferrocino, Francesca De Filippis, Mauro Fontana, Kalliopi Rantsiou, Danilo Ercolini e Luca Cocolin. "Microbiota of an Italian Grana-Like Cheese during Manufacture and Ripening, Unraveled by 16S rRNA-Based Approaches". Applied and Environmental Microbiology 82, n. 13 (22 aprile 2016): 3988–95. http://dx.doi.org/10.1128/aem.00999-16.
Testo completoAbstract (sommario):
ABSTRACTThe microbial ecology of cheese involves a rich and complex interaction between starter lactic acid bacteria and nonstarter lactic acid bacteria (NSLAB), mainly originating from raw milk and/or from the environment, that can contribute to the final characteristics of cheese. The aim of the present research was the exploration of the active microbiota by RNA-based approaches during the manufacturing and ripening of a Grana-like cheese. Reverse transcriptase PCR (RT-PCR)-denaturing gradient gel electrophoresis (DGGE) and RNA-based high-throughput sequencing were applied to profile microbial populations, while the enumeration of active bacteria was carried out by using quantitative PCR (qPCR). Three different cheese productions (named D, E, and F) collected in the same month from the same dairy plant were analyzed. The application of the qPCR protocol revealed the presence of 7 log CFU/ml of bacterial load in raw milk, while, during ripening, active bacterial populations ranged from <4 to 8 log CFU/ml. The natural whey starters used in the three productions showed the same microbiota composition, characterized by the presence ofLactobacillus helveticusandLactobacillus delbrueckii. Nevertheless, beta-diversity analysis of the 16S rRNA sequencing data and RT-PCR-DGGE showed a clear clustering of the samples according to the three productions, probably driven by the different milks used. Milk samples were found to be characterized by the presence of several contaminants, such asPropionibacterium acnes,Acidovorax,Acinetobacter,Pseudomonas, and NSLAB. The core genera of the starter tended to limit the development of the spoilage bacteria only in two of the three batches. This study underlines the influence of different factors that can affect the final microbiota composition of the artisanal cheese.IMPORTANCEThis study highlights the importance of the quality of the raw milk in the production of a hard cheese. Independent from the use of a starter culture, raw milk with low microbiological quality can negatively affect the populations of lactic acid bacteria and, as a consequence, impact the quality of the final product due to metabolic processes associated with spoilage bacteria.
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Syachroni, Fatma Maruddin, Farida Nur Yuliati e Andi Nurul Mukhlisah. "Pengaruh Kombinasi Starter Kultur Lactobacillus plantarum dan Lactobacillus acidophillus terhadap Karakteristik Mikrobiologis dan Kimiwawi pada Minuman Fermentasi." Jurnal Sains dan Teknologi Peternakan 1, n. 2 (5 giugno 2020): 36–41. http://dx.doi.org/10.31605/jstp.v1i2.708.
Testo completoAbstract (sommario):
Lactobacillus plantarum and Lactobacillus acidophilus are a probiotic bacteria which can be combined as a starter fermentation products using fresh milk and reconstitution milk as a growth medium. The aim of this study was to determine the combined effect of L. plantarum and L. acidophilus on total bacteria, lactic acid, and pH levels were used as a starter culture fermented milk beverage. The study was designed using a completely randomized design (CRD) 3 treatments (a combination of 1:1, 1:2, and 2:1) with 5 replications. The results showed that the number of bacteria at the level of a combination of 1:1, 1:2, and 2:1 respectively were 8.96±5.80; 8.22±5.80 and 8.72±5.80 (log cfu/ml), lactic acid content were 0.36±0.008 %; 0.41±0.008 %; and 0.49±0.008 %, and the pH were 4.91±0.02; 4.67±0.02; and 4.54±0.02. The best combination of L. plantarum and L. acidophilus bacteria for fermented milk was 1:1 based on the growth activity of lactic acid bacteria and pH.
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CHAMPAGNE, CLAUDE P., e NANCY GARDNER. "Enumeration of Psychrotrophic Bacteria in Raw Milk Inoculated with Lactic Acid Bacteria by the Agar Droplet Method". Journal of Food Protection 53, n. 3 (1 marzo 1990): 241–44. http://dx.doi.org/10.4315/0362-028x-53.3.241.
Testo completoAbstract (sommario):
Selected cultures of lactic acid bacteria (LAB) can be added to raw milk with the aim of inhibiting growth of pyschrotrophic bacteria. We compared the standard pour plate method (7°C/10 d) and a rapid surface plate method (18°C/45 h) with the agar droplet method for enumeration of psychrotrophs in raw milks seeded with LAB. The LAB did not interfere with the standard method or the 7°C/5 d agar droplet method, but interfered with the surface plate method. High correlations were obtained between the standard method and the agar droplet method (7°C) in uninoculated raw milk. High correlations were also found when LAB were added, but only when agar droplet plates were read after 4 or 5 d of incubation (7°C); sharp decreases in correlations were observed upon further incubation. Correlations between standard method and agar droplet method (7°C) were influenced by the LAB culture added as well as their level of inoculation. Inoculation levels greater than 106 per mL produced a decrease in correlation.
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Bojanic-Rasovic, Mirjana. "Potential of indigenous lactobacilli as starter culture in dairy products". Acta Periodica Technologica, n. 48 (2017): 39–52. http://dx.doi.org/10.2298/apt1748039b.
Testo completoAbstract (sommario):
Traditional production of fermented dairy products involves lactic acid bacteria that are normally present in the milk and production environment. These lactic acid bacteria represent the niche microbiota of the geographical area and they are responsible for local types of fermented products. In order to standardize indigenous products, the basic requirement is the application of the determined indigenous lactic acid bacteria as starter cultures affecting their specific characteristics by performing fermentation and influencing the ripening process. In the process of cheese fermentation usually participate bacteria of the genus Lactococcus and homofermentative lactobacilli. However, the process ripening is influenced mainly by the so-called nonstarter lactic acid bacteria - lactobacilli and secondary microflora. Lactobacilli during ripening of cheese continue to breakdown the rest of lactose, but they are primarily important in the process of protein breakdown. During metabolism of sugars and amino acids, lactobacilli produce aromatic compounds which have a positive effect on the flavor of the product. Some species of lactobacilli are available as probiotics. Some lactobacilli produce bacteriocins, which prevent the growth of pathogens, as well as many spoilage microorganisms. Indigenous lactobacilli have application especially in the production of typical local dairy products that are well accepted by the local population. Besides that, the use of indigenous lactic acid bacteria as starter cultures allows the production of cheese with designated geographical origin that could be placed on the international market. Consequently, indigenous lactic acid bacteria are a challenge for further research and possible their practical application in the dairy industry.
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Martín-Platero, Antonio M., Eva Valdivia, Mercedes Maqueda, Inés Martín-Sánchez e Manuel Martínez-Bueno. "Polyphasic Approach to Bacterial Dynamics during the Ripening of Spanish Farmhouse Cheese, Using Culture-Dependent and -Independent Methods". Applied and Environmental Microbiology 74, n. 18 (25 luglio 2008): 5662–73. http://dx.doi.org/10.1128/aem.00418-08.
Testo completoAbstract (sommario):
ABSTRACT We studied the dynamics of the microbial population during ripening of Cueva de la Magahá cheese using a combination of classical and molecular techniques. Samples taken during ripening of this Spanish goat's milk cheese in which Lactococcus lactis and Streptococcus thermophilus were used as starter cultures were analyzed. All bacterial isolates were clustered by using randomly amplified polymorphic DNA (RAPD) and identified by 16S rRNA gene sequencing, species-specific PCR, and multiplex PCR. Our results indicate that the majority of the 225 strains isolated and enumerated on solid media during the ripening period were nonstarter lactic acid bacteria, and Lactobacillus paracasei was the most abundant species. Other Lactobacillus species, such as Lactobacillus plantarum and Lactobacillus parabuchneri, were also detected at the beginning and end of ripening, respectively. Non-lactic-acid bacteria, mainly Kocuria and Staphylococcus strains, were also detected at the end of the ripening period. Microbial community dynamics determined by temporal temperature gradient gel electrophoresis provided a more precise estimate of the distribution of bacteria and enabled us to detect Lactobacillus curvatus and the starter bacteria S. thermophilus and L. lactis, which were not isolated. Surprisingly, the bacterium most frequently found using culture-dependent analysis, L. paracasei, was scarcely detected by this molecular approach. Finally, we studied the composition of the lactobacilli and their evolution by using length heterogeneity PCR.
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Tsuda, Harutoshi, e Kana Kodama. "Evaluating the technological properties of lactic acid bacteria in Wagyu cattle milk". Journal of Dairy Research 88, n. 2 (maggio 2021): 210–16. http://dx.doi.org/10.1017/s0022029921000339.
Testo completoAbstract (sommario):
AbstractThis 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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Ha, Thi Quyen, e Thi Minh Tu Hoa. "Selection of lactic acid bacteria producing bacteriocin". Journal of Vietnamese Environment 8, n. 5 (17 gennaio 2017): 271–76. http://dx.doi.org/10.13141/jve.vol8.no5.pp271-276.
Testo completoAbstract (sommario):
Lactic acid bacteria were isolated from 10 samples of the traditionally fermented foods (5 samples of Vietnamese fermented pork roll and 5 samples of the salted field cabbage) and 5 samples of fresh cow milks collected from households in Vietnam. 22 strains of lactic acid bacteria were isolated for inhibition to Lactobacillus plantarum JCM 1149. Of these, only 2 strains including DC1.8 and NC1.2 have rod shape, the others have coccus shape. 7 strains showing higher antibacterial activity were selected for checking spectrum of antibacteria with indicator bacteria consistting of Bacillus subtilis ATCC 6633, Enterococcus faecium JCM 5804 and Staphylococcus aureus TLU. By which, 3 strains including NC3.5 (from Vietnamese fermented pork roll), DC1.8 (from salted field cabbage) and MC3.19 (from fresh cow milk) were selected because of their higher antibacterial ability. However, the antibacterial activity of the lactic acid bacteria can be based on their disposable compounds and some other antibacterial compounds produced during their growth (such as lactic acid, H2O2, bacteriocins, etc.). For seeking lactic acid bacteria with capability of producing bacteriocins, antibacterial compounds with protein nature, 3 above strains were checked sensitiveness to proteases (including protease K, papain, α – chymotrypsin and trypsin). Because bacteriocins are proteinaceous antibacterial compounds, so their antibacterial activity will be reduced if proteases are added. The result showed DC1.8 and MC3.19 were capable of producing bacteriocin during culture process. They were identified as Lactobacillus acidophilus and Lactococcus lactis and classified, respectively, based on analysis chemical characterisitcs by standard API 50 CHL kit and phylogeny relationship by 16s rRNA sequences.
Các chủng vi khuẩn lactic được phân lập từ 10 mẫu thực phẩm lên men truyền thống (5 mẫu nem chua, 5 mẫu dưa cải bẹ muối) và 5 mẫu sữa bò tươi được thu thập từ các hộ gia đình ở Việt Nam. 22 chủng vi khuẩn lactic đã được phân lập với tiêu chí có khả năng kháng lại vi khuẩn kiểm định Lactobacillus plantarum JCM 1149. Trong số đó, 2 chủng DC1.8 và NC1.2 có tế bào hình que, các chủng còn lại có tế bào hình cầu. 7 chủng thể hiện hoạt tính kháng khuẩn cao được lựa chọn để xác định phổ kháng khuẩn rộng hơn với ba loài vi khuẩn kiểm định Bacillus subtilis ATCC 6633, Enterococcus faecium JCM 5804 và Staphylococcus aureus TLU. Từ đó lựa chọn được 3 chủng có hoạt tính kháng khuẩn cao hơn hẳn. Các chủng này gồm NC3.5 phân lập từ nem chua, DC1.8 phân lập từ dưa cải bẹ muối và MC3.19 phân lập từ sữa bò tươi. Tuy nhiên, hoạt tính kháng khuẩn của vi khuẩn lactic bao gồm những hợp chất nội tại có trong nó và cả những hợp chất được sinh ra trong quá trình phát triển của nó (như axit lactic, H2O2, bacteriocin, …). Với định hướng tìm chủng vi khuẩn lactic có khả năng sinh bacteriocin, chất kháng khuẩn có bản chất protein, 3 chủng trên được kiểm tra độ nhạy cảm với các protease (gồm protease K, papain, α – chymotrypsin và trypsin). Do bacteriocin là chất kháng khuẩn có bản chất protein nên hoạt tính kháng khuẩn của chúng sẽ bị giảm nếu protease được bổ xung vào. Kết quả lựa chọn được chủng DC1.8 và MC3.19 có khả năng sinh bacteriocin. Hai chủng này được phân loại đến loài nhờ vào phân tích đặc điểm sinh hóa bằng kit API 50 CHL và mối quan hệ di truyền thông qua trình tự gen 16s rRNA. Kết quả phân loại đã xác định chủng DC1.8 thuộc loài Lactobacillus acidophilus và chủng MC3.19 thuộc loài Lactococcus lactis.
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MONTEAGUDO-MERA, A., I. CARO, L. B. RODRÍGUEZ-APARICIO, J. RÚA, M. A. FERRERO e M. R. GARCÍA-ARMESTO. "Characterization of Certain Bacterial Strains for Potential Use as Starter or Probiotic Cultures in Dairy Products". Journal of Food Protection 74, n. 8 (1 agosto 2011): 1379–86. http://dx.doi.org/10.4315/0362-028x.jfp-10-392.
Testo completoAbstract (sommario):
The present work was aimed at characterizing 12 strains of lactic acid bacteria (LAB) to obtain improved potential starter or probiotic cultures that could be used for making dairy products from ewe's milk and cow's milk. Eight strains with antimicrobial properties, isolated from ewe's milk and from cheese made from ewe's and/or cow's milk, were studied. They were identified as Enterococcus faecalis (five strains), Lactococcus lactis subsp. cremoris, Leuconostoc mesenteroides, and Lactobacillus paracasei subsp. paracasei (one strain of each species). Additionally, four strains were obtained from the American Type Culture Collection: Lactobacillus casei 393 (isolated from cheese), L. lactis subsp. lactis 11454 (origin nonspecified and a producer of nisin), and two strains isolated from human feces (L. paracasei subsp. paracasei 27092 and Lactobacillus rhamnosus 53103, antibacterial agent producer). All E. faecalis strains showed at least one virulence factor (either hemolysin or gelatinase), which emphasizes the importance of these studies in this species. Both L. lactis strains and most Lactobacillus spp. were good acidifiers in ewe's milk and cow's milk at 30°C. High β-galactosidase activity, as well as aminopeptidase activities that favor the development of desirable flavors in cheese, were detected in all Lactobacillus spp. strains. Furthermore, L. rhamnosus ATCC 53103 showed α-fucosidase activity (thought to help colonization of the intestine) and lack of α-glucosidase activity (a trait considered positive for diabetic and obese humans). This last enzymatic activity was also lacking in L. lactis ATCC 11454. L. mesenteroides was the only strain D(−)-lactic acid producer. The selection of any particular strain for probiotic or dairy cultures should be performed according to the technological and/or functional abilities needed.
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Hosoda, Masataka, Hideo Hashimoto, Hirotsugu Morita, Midori Chiba e Akiyoshi Hosono. "Antimutagenicity of Milk Cultured with Lactic Acid Bacteria Against N-Methyl-N’-Nitro-N-Nitrosoguanidine". Journal of Dairy Science 75, n. 4 (aprile 1992): 976–81. http://dx.doi.org/10.3168/jds.s0022-0302(92)77839-4.
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HOSONO, Akiyoshi, e Hidekazu SHIRAI. "Antimutagenicity of Milk Cultured with Lactic Acid Bacteria Against the Heated Solution of Cysteine-Glucose". Nihon Chikusan Gakkaiho 67, n. 12 (1996): 1076–81. http://dx.doi.org/10.2508/chikusan.67.1076.
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SUÁREZ, V. B., M. L. CAPRA, M. RIVERA e J. A. REINHEIMER. "Inactivation of Calcium-Dependent Lactic Acid Bacteria Phages by Phosphates". Journal of Food Protection 70, n. 6 (1 giugno 2007): 1518–22. http://dx.doi.org/10.4315/0362-028x-70.6.1518.
Testo completoAbstract (sommario):
The capacity of three phosphates to interrupt the lytic cycle of four specific autochthonal bacteriophages of lactic acid bacteria used as starters was assayed. The phosphates used (polyphosphates A and B and sodium tripolyphosphate–high solubility [TAS]) were selected on the basis of their capacity to sequester divalent cations, which are involved in the lytic cycle of certain bacteriophages. The assays were performed in culture media (deMan Rogosa Sharpe and Elliker broths) and reconstituted (10%, wt/vol) commercial skim milk to which phosphates had been added at concentrations of 0.1, 0.3, and 0.5% (wt/vol). Phosphate TAS was the most inhibitory one, since it was able to inhibit the lytic cycle of all bacteriophages studied, in both broths and milk. In broth, polyphosphates A and B inhibited the lytic cycle of only two bacteriophages at the maximal concentration used (0.5%), whereas in milk, they were not capable of maintaining the same inhibitory effect.
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OUMER, A., S. GARDE, P. GAYA, M. MEDINA e M. NUÑEZ. "The Effects of Cultivating Lactic Starter Cultures with Bacteriocin-Producing Lactic Acid Bacteria". Journal of Food Protection 64, n. 1 (1 gennaio 2001): 81–86. http://dx.doi.org/10.4315/0362-028x-64.1.81.
Testo completoAbstract (sommario):
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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Rubak, Yuliana Tandi, Lilis Nuraida, Dyah Iswantini e Endang Prangdimurti. "Angiotensin-I-converting enzyme inhibitory peptides in milk fermented by indigenous lactic acid bacteria". February-2020 13, n. 2 (2020): 345–53. http://dx.doi.org/10.14202/vetworld.2020.345-353.
Testo completoAbstract (sommario):
Background and Aim: Fermented milk can be used to produce antihypertensive peptides. Lactic acid bacteria (LAB) with its proteolytic system hydrolyze milk protein during fermentation to produce several peptides, which include antihypertensive bioactive peptides. This study aimed to investigate the ability of indigenous LAB for the production of angiotensin-I-converting enzyme inhibitory (ACE-I) peptides in fermented milk and to characterize the ACEI peptides. Materials and Methods: Reconstituted milk (11%) inoculated with ten LAB isolates, and then incubated at 37°C until it reaches pH 4.6. The evaluation was carried out for LAB count, lactic acid concentration, peptide content, and ACE-I activity. The low molecular weight (MW) peptides (<3 kDa) were identified using Nano LC Ultimate 3000 series system Tandem Q Exactive Plus Orbitrap high-resolution mass spectrometry. Results: The result showed that the ten LAB isolates were able to produce ACE-I in fermented milk with the activities in the range of 22.78±2.55-57.36±5.40%. The activity of ACE-I above 50% produced by Lactobacillus delbrueckii BD7, Lactococcus lactis ssp. lactis BD17, and Lactobacillus kefiri YK4 and JK17, with the highest activity of ACE-I produced by L. kefiri YK4 (IC50 0.261 mg/mL) and L. kefiri JK17 (IC50 0.308 mg/mL). Results of peptide identification showed that L. kefiri YK 4 could release as many as 1329, while L. kefiri JK 17 could release 174 peptides. The peptides produced were 95% derived from casein. The other peptides were from α-lactalbumin, β-lactoglobulin, and serum amyloid A. The peptides produced consisted of 6-19 amino acid residues, with MWs of 634-2079 Dalton and detected at 317-1093 m/z. A total of 30 peptides have been recognized based on literature searches as ACE-I peptides (sequence similarity: 100%). Conclusion: L. kefiri YK4 and JK17 are the potential to be used as starter cultures to produce the bioactive peptide as ACE-I in fermented milk.
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MD Makut, NJ Emelogu, IK Ekeleme, JE Owuna e FU Alfa. "Antimicrobial activity of lactic acid bacteria isolated from locally fermented cow milk products sold in Keffi, Nigeria on clinical bacteria". GSC Advanced Research and Reviews 8, n. 2 (30 agosto 2021): 078–84. http://dx.doi.org/10.30574/gscarr.2021.8.2.0165.
Testo completoAbstract (sommario):
Lactic acid bacteria (LAB) are renowned for the potential of producing antimicrobial compounds. This study focuses on isolation and antimicrobial effect of lactic acid bacteria isolated from locally fermented cow milk products (Nono, Kindirmo and Maishanu). The antimicrobial effect of the LAB isolates against clinical test isolates was also investigated. Fifty (50) samples each of Nono and Kindirmo, and twenty-five (25) of Maishanu were collected from cow milk products sellers in Keffi, Nasarawa State Nigeria. Standard microbiological methods were used for the isolation and identification of Lactic acid bacteria from fermented cow milk products. The percentage isolation rate of Lactobacillus species from Nono and Kindirmo showed that 52.0% were isolated from Nono and 58.0% from kindirmo. The highest percentage occurring Lactobacillus species from Nono was Lactobacillus plantarum (14.0%) and the highest percentage occurring Lactobacillus species from kindirmo was Lactobacillus delbrueckii (16.0%). The Lactobacillus species isolated were screened for antibacterial activity and it was observed that seven (7) were able to show inhibition zones. The antimicrobial effect of the LAB culture supernatant against clinical isolates of Staphylococcus aureus, Escherichia coli and Shigella dysenteriae was investigated using agar diffusion technique. The highest 22.00mm was observed by Lactobacillus delbrueckii and Lactobacillus delbrueckii against Shigella dysenteriae, while the least inhibition zone of 15.00mm was observed by Lactobacillus delbrueckii and Lactobacillus acidophilus against E. coli. In conclusion, the zones of inhibition observed in this research strongly suggest that various antimicrobial compounds (lactic acid, acetic acid, propionic acid and bacteriocins) produced during the fermentation process are potent in the control of growth of the test bacteria.
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Montanuci, Flávia Daiana, Tatiana Colombo Pimentel, Sandra Garcia e Sandra Helena Prudencio. "Effect of starter culture and inulin addition on microbial viability, texture, and chemical characteristics of whole or skim milk Kefir". Food Science and Technology 32, n. 4 (13 novembre 2012): 580–865. http://dx.doi.org/10.1590/s0101-20612012005000119.
Testo completoAbstract (sommario):
The effect of inulin addition and starters (Kefir grains or commercial starter culture) on the microbial viability, texture, and chemical characteristics of Kefir beverages prepared with whole or skim milk was evaluated during refrigerated storage. The type of starter did not influence microbial viability during the storage of the beverages, but the chemical and textural changes (decreases in pH, lactose concentration, and inulin and increased acidity, firmness, and syneresis) were more pronounced in the formulations fermented with grains than those fermented with the starter culture. The addition of inulin did not influence acidity or viability of lactic acid bacteria, but in general, its effect on the survival of acetic acid bacteria, Lactococcus and yeasts, firmness, and syneresis depended on the type of milk and starter culture used. Generally, the yeast, acetic acid bacteria, and Leuconostoc counts increased or remained unchanged, while the total population of lactic acid bacteria and Lactococcus were either reduced by 1 to 2 logs or remained unchanged during storage.
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Terzic-Vidojevic, Amarela, Sanja Mihajlovic, Gordana Uzelac, Natasa Golic, Dj Fira, M. Kojic e Lj Topisirovic. "Identification and characterization of lactic acid bacteria isolated from artisanal white brined Golija cows’ milk cheeses". Archives of Biological Sciences 66, n. 1 (2014): 179–92. http://dx.doi.org/10.2298/abs1401179t.
Testo completoAbstract (sommario):
The aim of this study was to identify and characterize the lactic acid bacteria (LAB) of artisanal Golija raw and cooked cows? milk cheeses traditionally manufactured without the addition of starter culture. A total of 188 Gram-positive and catalase-negative isolates of Golija cheeses were obtained from seven samples of different ripening time. Phenotypebased assays as well as rep-PCR and 16S rDNA sequence analysis were undertaken for all 188 Lstrains. The most diverse species were isolated from 20-day-old BGGO8 cheese (Lactobacillus fermentum, Lactobacillus plantarum, Lactobacillus casei/paracasei, Lactobacillus sucicola, Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. lactis bv. diacetylactis, Enterococcus faecium, Enterococcus durans and Leuconostoc mesenteroides). In other Golija cheeses Lactobacillus reuteri, Lactobacillus curvatus, Lactobacillus rhamnosus, Lactococcus lactis subsp. cremoris, Lactococcus garvieae, Streptococcus thermophilus and Leuconostoc pseudomesenteroides were found. Pronounced antimicrobial properties showed enterococci (13/42) and lactococci (12/31), while the good proteolytic activity demonstrated lactococci (13/31) and lactobacilli (10/29).
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THIERRY, ANNE, DELPHINE SALVAT-BRUNAUD e JEAN-LOUIS MAUBOIS. "Influence of thermophilic lactic acid bacteria strains on propionibacteria growth and lactate consumption in an Emmental juice-like medium". Journal of Dairy Research 66, n. 1 (febbraio 1999): 105–13. http://dx.doi.org/10.1017/s0022029998003331.
Testo completoAbstract (sommario):
Swiss-type cheeses such as Emmental are characterized by the successive development of thermophilic lactic acid bacteria (TLAB) and propionibacteria. The aim of this study was to determine whether the choice of TLAB strain influenced propionibacteria. TLAB and propionibacteria were cultured sequentially under the conditions prevailing in cheese. Firstly, 11 Emmental juice-like media were prepared by fermenting casein-enriched milk with pure or mixed cultures of TLAB (Lactobacillus helveticus, Lb. delbrueckii subsp. lactis and Streptococcus thermophilus), differing in their proteolytic activities. TLAB cells were then removed by microfiltration. Finally, five strains of Propionibacterium freudenreichii were grown on these media at 24°C under anaerobiosis and their growth characteristics and lactate consumption determined. The media mainly differed in their contents of peptides (1·9–5·3 g/kg) and free amino acids (1·0–5·6 g/kg) and the proportions of lactate isomers (42–92% of the L(+) isomer). Propionibacteria were significantly (P<0·05) influenced by TLAB strains (differences in doubling times of up to 20% and differences in lactate consumption after 600 h culture of up to 52%). The influence of TLAB was similar for all the propionibacteria tested, depended on the TLAB strains and could not be generalized to the TLAB species. Propionibacteria were stimulated by high peptide levels, low levels of free amino acids and NaCl, a low proportion of L(+)-lactate and other undetermined factors. However, variations due to TLAB were less than those between propionibacteria strains.
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Bojanic-Rasovic, Mirjana, Sigrid Mayrhofer, Mary Ochome, Erna Ajanovic, Marija Zunabovic, Aleksandra Martinovic e Konrad Domig. "Diversity of lactic acid bacteria isolated from traditional Montenegrin dairy products". Genetika 50, n. 2 (2018): 465–82. http://dx.doi.org/10.2298/gensr1802465b.
Testo completoAbstract (sommario):
Traditional production of fermented dairy products in Montenegro is carried out without adding defined starter cultures. This way of production involves lactic acid bacteria (LAB) that are normally present in the raw milk and production environment. This autochthonous ("wild") fermentation microbiota represents a reservoir of unknown strains. In order to study the LAB diversity, 25 indigenous dairy products in Montenegro have been tested. Isolation was performed on microbial media M17 and MRS agar with or without supplementations under aerobic and anaerobic conditions at temperatures of 30?C, 37 ?C and 44?C. Identification of these isolates at species level was done by species-specific PCR and gene regions sequencing of representatives of each RAPD-cluster. RAPD-PCR was used to characterize the isolates at strain level. Nine Lactobacillus species, five Leuconostoc species, four Enterococcus species as well as strains of the species Lactococcus lactis, Pediococcus pentosaceus and Streptococcus thermophilus were detected. It can be concluded that a rich lactic acid bacteria diversity existed in the analyzed Montenegrin dairy products. Further examination of the isolates could lead to the development of autochthonous starter cultures that would contribute to a product that is characteristic for the geographical area and to which the local population is accustomed.
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Paliy, A. P., S. O. Gujvinska e M. S. Alrawashdeh. "Selection of technological regime and cryoprotector for lyophilization of lactobacteria (Lactobacillus spp.)". Ukrainian Journal of Ecology 10, n. 4 (10 agosto 2020): 184–90. http://dx.doi.org/10.15421/2020_186.
Testo completoAbstract (sommario):
Despite the success achieved in the comprehensive study of probiotic cultures, today there are a number of problems associated with the low viability of lactic acid bacteria during their processing and long-term storage in probiotics. Our work aimed to select the optimal technological regime and cryoprotectant to preserve the viability of lactic acid bacteria Lactobacillus spp. during their lyophilization. According to the results of the conducted researches, it is established that for freeze-drying of probiotic cultures Lactobacillus spp. in the facility LZ-45.27 (Frigera, Czech Republic) the most optimal is the mode which provides a rise of temperature within 45 hours from minus 70.0±1.0 °C to plus 26.0±1.0 °C with a speed of 2.2±0.1 °C/hour. It is effective to use protective media for lactobacilli, which consist of: skim milk (90%) and sucrose (10%); skim milk (90%) and lactose (10%); skim milk (90%), glucose (2.5%), sucrose (2.5%), lactose (5.0%) (P≤0.05). Freeze-drying of lactic acid bacteria under optimal conditions and the addition of cryoprotectants will avoid the problems associated with a significant reduction in the number of microbial cells. The results of research can be used for long-term storage of cultures of lactobacilli by their lyophilization.