Microbiological analysis of Greek Protected Designation of Origin cheeses and characterisation of the isolated lactic acid bacteria

Formaggio di Fossa di Sogliano is a traditional Italian Protected Designation of Origin (PDO) cheese ripened for a minimum of 5 months, with the feature of a ripening of at least 80 to at most 100 days in pits, digged into tuffaceous rocks according to medieval tradition of Italy. In this study, a challenge test using Listeria innocua as a surrogate of Listeria monocytogenes was performed, with the aim of increasing knowledge concerning the impact of the Fossa cheese process, and especially of the traditional ripening process of this PDO, on the behaviour of L. monocytogenes. Pasteurized milk was experimentally inoculated with 4.5 log CFU/mL cocktail by three L. innocua strains, and L. innocua and Mesophilic Lactic Acid Bacteria (LAB) counts as well as the evolution of temperatures, pH and aw values were monitored throughout the manufacturing and ripening processes. Throughout the ripening in maturation room a constant temperature of 8°C was observed reaching a temperature between 10 and 15.5°C during ripening into pit. In the final products data for LAB concentration, pH and aw values were roughly in accordance with literature, even if some differences were, probably due to variability of artisanal cheese productions. The numbers of L. innocua showed a slight decrease but remained stable until the end of ripening in maturation room, whereas a significant reduction of the microorganism was observed in the final product, at the end of the ripening into the pit. The findings give scientific evidence that the process of this PDO prevented the L. innocua growth, allowing us to speculate a similar behaviour of L. monocytogenes. Based on this study, the recommendation to extend as much as possible the ripening into pit (from 80 to 100 days) was provided to food business operators as a risk mitigation strategy to be implemented.

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Characterization of Lactic Acid Bacteria Isolated from Traditional Butter Produced in Djelfa Province of Algeria

Biosciences Biotechnology Research Asia ◽

10.13005/bbra/2683 ◽

2018 ◽

Vol 15 (3) ◽

pp. 737-746

Author(s):

Guetouache Mourad ◽

Guessas Bettache

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Rural Areas ◽

Lactobacillus Brevis ◽

Fecal Coliforms ◽

Microbiological Analysis ◽

Physiological And Biochemical Characteristics ◽

Genus Lactobacillus ◽

Aerobic Flora

Morphological, physiological and biochemical characteristics were employed to identify lactic acid bacteria (LAB), isolated from traditional (butter) was collected from different rural areas of the province of Djelfa. Among 177 isolates, 79 lactic acid bacterial (LAB) strains were isolated and purified. The results obtained show that the isolates obtained belong to the following genus Lactobacillus, Lactococcus, Enterococci and Leuconostoc characterize the biodiversity of this traditional butter studied. Only Gram-positive and catalase negative isolates were identified at species level. The most common LAB belonging to the species Lactobacillus alimentarius (15.19 %), Lactobacillus plantarum (22.78 %), Lactobacillus fermentum (18.99 %), Lactobacillus brevis (06.33 %), Lactococcus lactis (12.66 %), Lactococcus cremoris (06.33 %), Leuconostoc mesenteroides (06.33 %) and Enterococcus faecalis (11.39 %). The samples pH average was 6.06 ± 0.34, microbiological analysis results were; total mesophilic aerobic flora (TMAF) (2, 22 ± 0, 68).10 3cfu/ml, total coliforms 0,54 ± 0.56 ufc/ml, fecal coliforms 0,6 ± 0.50 cfu/ml, yeast (0,48 ± 0.31). 10 cfu/ml, Staphylococcus aureus, Salmonella and moulds weren’t detected.

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Assessment of an Excision Surface Sampling Method for Microbiological Analysis of Lamb Liver

Journal of Food Protection ◽

10.4315/0362-028x-56.1.58 ◽

1993 ◽

Vol 56 (1) ◽

pp. 58-61 ◽

Cited By ~ 5

Author(s):

TERESA RIVAS ◽

ANTONIO HERRERA ◽

AGUSTIN ARIÑO

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Sampling Method ◽

Microbiological Analysis ◽

Surface Sampling ◽

Plate Counts

Reproducibility of an excision surface sampling method for the microbiological analysis of 204 samples of spoiled and nonspoiled lamb liver was studied. The procedure consisted of removing a 5-cm2 area from the liver (1–2 mm in thickness) with sterile scalpel and metal templates. Since variation was observed in the thickness of the excised portions taken from different livers, all excised samples were weighed and results for microbiological analysis (aerobic Plate counts at 30 and 7°C, Enterobacteriaceae, Pseudomonas, and lactic acid bacteria counts) were expressed as both log CFU/cm2 and log CFU/g. For all groups of microorganisms studied, in both spoiled and nonspoiled samples, a highly significant correlation was found (r ≥ 0.996, p < 0.0001) between results expressed as log CFU/cm2 and log CFU/g.

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Evaluation of microbial and sensory properties of flavored yogurt drink produced by Noaea mucronata and liquid smoke treatment

Infectious Diseases and Herbal Medicine ◽

10.4081/idhm.2020.77 ◽

2020 ◽

Vol 1 (1) ◽

Author(s):

Ghazal Rahimzadeh ◽

Abdullatif Tay ◽

Joe Mac Regenstein ◽

Asad Rokhzadi ◽

Hossein Dabiri

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Sensory Evaluation ◽

Sensory Attributes ◽

Microbiological Analysis ◽

Liquid Smoke ◽

Analysis Application ◽

Yogurt Drink ◽

Total Bacteria ◽

Control Samples

Liquid smoke is more acceptable compared with traditional smoking for various practical and health reasons. This study aimed to investigate the quality attributes of yogurt drink treated with natural and liquid smoke. Yogurt drink samples were divided into four groups; natural smoked, liquid smoked at two concentrations (1 and 2 mL·L-1) and un-smoked control samples. Microbial and sensory attributes of yogurt drink samples were analyzed after 1, 7, 14, and 21 days of storage at 4°C. The final counts of total bacteria, lactic acid bacteria, yeast and molds were significantly lower after the application of 2 mL·L-1 liquid smoke compared to control samples. Moreover, lactic acid bacteria of yogurt drink were not inhibited by natural smoke or 1 mL·L-1 liquid smoke treatments. According to the sensory evaluation and microbiological analysis, application of 1 mL·L-1 of liquid smoke in yogurt drink is the most appropriate and convenient alternative to the traditional smoking method.

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Large Genetic Intraspecific Diversity of Autochthonous Lactic Acid Bacteria and Yeasts Isolated from PDO Tuscan Bread Sourdough

Applied Sciences ◽

10.3390/app10031043 ◽

2020 ◽

Vol 10 (3) ◽

pp. 1043

Author(s):

Michela Palla ◽

Caterina Cristani ◽

Manuela Giovannetti ◽

Monica Agnolucci

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Random Amplified Polymorphic Dna ◽

Intraspecific Variability ◽

Starter Cultures ◽

Intraspecific Diversity ◽

Baked Goods ◽

Protected Designation Of Origin ◽

Complex Microbial Community ◽

Rapd Pcr

The diverse metabolites, positively affecting the nutritional, organoleptic and technological traits of leavened baked goods, are produced by different sourdough lactic acid bacteria (LAB) and yeast strains, as the result of their genetic intraspecific diversity. Therefore, the molecular and functional strain-level characterization of sourdough microbiota is crucial to valorize traditional or origin protected baked end-products, develop innovative starter cultures and design functional cereal-based foods. To this aim, the genetic intraspecific diversity of 96 Lactobacillus sanfranciscensis, 65 Kazachstania humilis and three Saccharomyces cerevisiae characterizing Protected Designation of Origin (PDO) Tuscan bread sourdough, was investigated, using P4, P7 and M13 random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR), (GTG)5 repetitive element sequence-based (rep)-PCR and inter-delta region analyses, respectively. Regarding LAB, the combination of P4, P7 and M13 RAPD-PCR analyses revealed a huge degree of intraspecific variability, discriminating 43 biotypes out of 96 isolates of L. sanfranciscensis. (GTG)5 rep-PCR showed a discriminatory index of 0.95, grouping the 65 K. humilis isolated from PDO Tuscan bread sourdough in 9 biotypes. The high polymorphism among both LAB and yeast isolates of PDO Tuscan bread sourdough outlines a highly complex microbial community structure, whose relative composition and specific physiological characteristics could be responsible for the peculiar organoleptic, rheological, nutritional and potentially nutraceutical features of PDO Tuscan bread.

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Exploration of the Microbial Biodiversity Associated with North Apulian Sourdoughs and the Effect of the Increasing Number of Inoculated Lactic Acid Bacteria Strains on the Biocontrol against Fungal Spoilage

Fermentation ◽

10.3390/fermentation5040097 ◽

2019 ◽

Vol 5 (4) ◽

pp. 97 ◽

Cited By ~ 2

Author(s):

Mattia Pia Arena ◽

Pasquale Russo ◽

Giuseppe Spano ◽

Vittorio Capozzi

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Shelf Life ◽

Restriction Analysis ◽

Rflp Analysis ◽

Food Preservation ◽

Rrna Gene ◽

Microbiological Analysis ◽

Bread Making ◽

Dna Restriction

In this study, we explored the diversity of yeasts and lactic acid bacteria (LAB) associated with six spontaneous sourdough fermentations from the northern part of the Apulian region (Italy). Bacterial and yeast isolates from sourdough were investigated by amplified ribosomal DNA restriction analysis (ARDRA) and restriction fragment length polymorphism (RFLP) analysis, respectively. The identification of the isolates was confirmed by sequencing bacterial 16S gene and yeast ITS1–5.8S–ITS2 rRNA gene amplicons. Microbiological analysis of all sourdough samples revealed that LAB and yeast counts ranged between 1.7 × 105 and 6.5 × 108 cfu/g, and 7.7 × 105 and 2.5 × 107 cfu/g, respectively. The molecular identification at species level revealed the occurrence of Lactobacillus plantarum as the dominant LAB and Saccharomyces cerevisiae as the dominant yeast species in all different sourdough samples. Then, the ability of all isolated strains to inhibit and/or reduce the growth of several selected fungi was valued through the overlay method. In light of their antifungal performances, ten LAB strains were inoculated, singularly and in combination, in subsequent bread-making trials. Overall, we confirmed the potential of LAB to extend the shelf life of bread through spoilage inhibition and, for the first time, we observed a synergistic effect due to the combination of several isolated LAB on the inhibition behavior against selected fungal spoilage strains. Our findings suggest the exploration of a LAB-based approach in order to extend the shelf life of bread, reducing, at the same time, the use of chemical agents for food preservation.

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Bovine mastitis prevention: humoral and cellular response of dairy cows inoculated with lactic acid bacteria at the dry-off period

Beneficial Microbes ◽

10.3920/bm2016.0194 ◽

2017 ◽

Vol 8 (4) ◽

pp. 589-596 ◽

Cited By ~ 11

Author(s):

M. Pellegrino ◽

N. Berardo ◽

J. Giraudo ◽

M.E.F. Nader-Macías ◽

C. Bogni

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Cellular Response ◽

Animal Feed ◽

Bovine Milk ◽

Bovine Mastitis ◽

Memory Cell ◽

Microbiological Analysis ◽

Mastitis Pathogens

The use of lactic acid bacteria (LAB) in animal feed, constitute an alternative tool for bovine mastitis prevention. Previously, two LAB strains were isolated from bovine milk and selected for their probiotics properties. So far, immune response of inoculating LAB in bovine udders at dry-off period has not been investigated. The immunoglobulin isotype levels and memory cell proliferation in blood and milk of animals inoculated with Lactobacillus lactis subsp. lactis CRL1655 and Lactobacillus perolens CRL1724 at dry-off period was studied. Ten animals were inoculated intramammarily with 106 cells of each LAB (IG) and 2 animals used as control (NIG). Milk and blood samples were taken before inoculation and 1, 2, 4, 6, 12 and 24 h and 7 and 14 days after inoculation. Somatic cell count (SCC) in milk, the presence of bovine mastitis pathogens, the levels of antibodies and lymphocyte proliferation were determined. In the IG, the SCC was <250,000 cells/ml up to 4 h after intramammary inoculation. Six and 12 h after inoculation, the SCC increased up to 600,000 and 2,000,000 cells/ml, respectively. In the NIG, the SCC reached the maximum value 7 days after inoculation. Microbiological analysis showed that all samples were negative for major bovine mastitis pathogens after 24-48 h of incubation. In general, LAB inoculation increased the amount of IgG isotypes in blood and milk, and these antibodies were able to recognise Staphylococcus aureus epitopes. Lymphocytes proliferation was significantly higher in the IG at all time points assayed, following LAB or S. aureus stimulation. The lymphocytes of animals inoculated with LAB do not react in vitro to the presence of S. aureus antigen.. The results showed that probiotic microorganisms could be a natural and effective alternative in the prevention of bovine mastitis at dry-off period and act as immunomodulatory stimulating local and systemic defence lines.

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Microflora and Physical-Chemical Characteristics of Omani Laban

Journal of Agricultural and Marine Sciences [JAMS] ◽

10.24200/jams.vol4iss2pp61-64 ◽

1999 ◽

Vol 4 (2) ◽

pp. 61

Author(s):

N. Guizani ◽

K. Al-Ramadani

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Lactobacillus Plantarum ◽

Lactococcus Lactis ◽

Titratable Acidity ◽

Fecal Coliforms ◽

Chemical Characteristics ◽

Microbiological Analysis ◽

Physical Chemical ◽

The Mean

Fifteen samples of Laban made at home in three Omani regions were subjected to physical-chemical and microbiological analysis. Laban had an average titratable acidity, pH, fat, protein and total solids of 1.12%, 3.98, 1.I2%, 2. 11% and 6.29%, respectively. The microbial flora of traditional Omani laban was found to be predominantly mesophilic lactococci. and homofemenentative lactobacili. The mean Lactococci and lactobacilli counts were 1.3 x 10 8 and 2.4 x 10 6/ml respectively. The main microbial types involved in the manufacture of Omani laban were Lactoeoccus lactis ssp lactis. Lacrococcus locus ssp locus biov. Diacetylactis, Lactococcus lactis ssp, Cremoris. and Lactobacillus plantarum. Leuconostoc species were present in low proportion compared to other lactic acid bacteria. All Laban samples contained high yeast numbers and were highly contaminated with coliforms, and fecal coliforms.

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Growth Modeling of Lactic Acid Bacteria and Microbiological Analysis in Two Types of Sliced Vacuum Package Cooked Ham

Revista Ciencias Exatas e Naturais ◽

10.5935/recen.2013.01.07 ◽

2013 ◽

Vol 15 (1) ◽

Author(s):

Simone Geitenes ◽

Mariana F. Batista de Oliveira ◽

Daneysa Lahis Kalschne ◽

Cleonice Mendes Pereira Sarmento

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Growth Modeling ◽

Microbiological Analysis ◽

Cooked Ham ◽

Vacuum Package

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KUALITAS EGGURT KERING DENGAN BAHAN DASAR SUSU DAN BERBAGAI MACAM BIJI-BIJIAN

Buletin Peternakan ◽

10.21059/buletinpeternak.v35i2.597 ◽

2012 ◽

Vol 35 (2) ◽

pp. 107

Author(s):

Indratiningsih (Indratiningsih) ◽

Nurliyani (Nurliyani) ◽

Rihastuti (Rihastuti) ◽

Endang Wahyuni ◽

Widodo (Widodo)

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Microbiological Quality ◽

Fermented Milk ◽

Lactobacillus Bulgaricus ◽

Microbiological Analysis ◽

Green Beans ◽

Black Soybean ◽

Sesame Seeds

This study aimed to determine the chemical, sensory, and microbiological quality of eggurt that was mixed with various grains of sesame, green bean, and black soybean. The addition of grains starch was intended to improve the chemical and sensory quality, as well as to maintain the viability of lactic acid bacteria (LAB) during drying. Eggurt was prepared by fermented milk and albumen inoculated with 5% Lactobacillus bulgaricus and Streptococcus thermophillus (1:1) and incubated at 42°C to form a curd or the pH reached 4.5. Milk and albumen were pasteurized separately. Milk was pasteurized at temperature of 85°C for 30 minutes, while the albumen was pasteurized at temperature of 63°C for 5 minutes. Dried eggurt was produced by mixing of eggurt and blended grain with a ratio of 2:1, and then dried at 50oC for 16 hours. After dried, the eggurt products were then sampled for chemical, sensory and microbiological analysis. The results showed that eggurt mixed with sesame seeds had a highest score on texture (47.50), aceptability (43.06) and total lactic acid bacteria (5.67 log CFU/g) than eggurt mixed with black soybeans and green beans, while eggurt mixed with black soybean had a highest score (P<0.01) on acidity (43.85), fat (9.13%) and protein content (33.06%). There was no different effect between grain sources on degree of sweetness, lactose concentration, pH and acidity levels. It can be concluded that eggurt-sesame has the best sensory and microbiological quality, while the best chemical quality was obtained from eggurt-black soybeans. (Keywords: Quality, Dried eggurt, Milk, Sesame, Green beans, Black soybeans)

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