Impact of Freezing on the Microbiological Quality and Physical Characteristics of Buffalo Mozzarella Cheese

Buffalo Mozzarella cheese from Campania is one of the most worldwide appreciated Italian dairy products. The increased demand for buffalo dairy products and the limited availability of the finest buffalo milk has prompted the diffusion of illicit practices, such as the use of milk, curd, or other products that are frozen or bought at low cost. The aim of this research was to provide preliminary results about the trend of the microbial communities of buffalo milk, curd and Buffalo Mozzarella cheese, during freezing storage of eleven months. At the same time, the alterations of physical properties and the presence of the molecular marker “γ4-casein”, have been investigated. The results showed that freezing reduced the concentrations of the total bacterial count, Enterobacteriaceae, coliforms, Escherichia coli and yeasts in fresh milk and, the concentrations of the total bacterial count, coliforms, lactic acid bacteria and yeasts in mature curd. In the finished product, no notable decreases were observed, except for lactic acid bacteria. About the γ4-casein, no increase was observed in all matrices. These preliminary results allow us to conclude that the freezing process if properly carried out, does not compromise the microbiological quality and the physical properties of the Buffalo Mozzarella cheese.

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Microbiological Quality of Rabbit Meat

Journal of Food Protection ◽

10.4315/0362-028x-67.5.966 ◽

2004 ◽

Vol 67 (5) ◽

pp. 966-971 ◽

Cited By ~ 18

Author(s):

JOSE M. RODRÍGUEZ-CALLEJA ◽

JESÚS A. SANTOS ◽

ANDRÉS OTERO ◽

MARÍA-LUISA GARCÍA-LÓPEZ

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Microbiological Quality ◽

Bacterial Count ◽

Meat Production ◽

Total Bacterial Count ◽

Indicator Organisms ◽

Ph Values ◽

Rabbit Meat ◽

Microbial Groups

World rabbit meat production is estimated to be over 1 million tons, and Spain is the third largest producer. Although rabbit meat is marketed and consumed worldwide, information on microbiological quality is very scarce. Here, we report indicator organisms, spoilage flora, sensory quality, and some physicochemical traits of 24 h postmortem chilled rabbit carcasses and prepackaged rabbit meat stored chilled in air for 0 to 3 days at the retail level. The mean total bacterial count (4.01 ± 0.48 log CFU/g) for carcasses dressed at a small abattoir by a manual process was significantly lower (P < 0.05) than that (4.96 ± 0.90 log CFU/g) for carcasses dressed at a large abattoir in automated slaughter lines. Both groups of carcasses had mean pH values of 5.98. The dominant contaminants on carcasses from the small abattoir were Pseudomonas, lactic acid bacteria, and yeasts. These microorganisms and Brochothrix thermosphacta were dominant on carcasses from the large abattoir. On prepacked hind legs (pH 6.26 ± 0.18) stored at −1 to + 1° C (supermarket 1), mean aerobic mesophilic count was 5.87 ± 1.03 log CFU/g, and the major microbial groups were Pseudomonas, yeasts, lactic acid bacteria, and B. thermosphacta. On prepacked whole carcasses (pH 6.37 ± 0.18) displayed at −1 to + 5° C (supermarket 2), mean aerobic mesophilic count was 6.60 ± 1.18 and the same microbial groups were dominant. Relative Escherichia coli incidence was supermarket 2 > large abattoir > supermarket 1 > small abattoir. Overall, low numbers of coliforms, Enterobacteriaceae, psychrotrophic clostridia, coagulase-positive staphylococci, and molds were found. Sensory scores, pH values, and L-lactic acid content differentiated fresh carcasses from retail samples. Data obtained suggest that the microflora of chilled rabbit meat are different from those found on the meat of other animals.

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The characteristic of sheep cheese “Bryndza” from different regions of Slovakia based on microbiological quality

Potravinarstvo Slovak Journal of Food Sciences ◽

10.5219/1239 ◽

2020 ◽

Vol 14 ◽

pp. 69-75 ◽

Cited By ~ 1

Author(s):

Miroslava Kačániová ◽

Ľudmila Nagyová ◽

Jana Štefániková ◽

Soňa Felsöciová ◽

Lucia Godočíková ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Kluyveromyces Lactis ◽

Microbiological Quality ◽

Aerobic Condition ◽

Plate Count ◽

Total Bacterial Count ◽

Microscopic Fungi ◽

Gram Positive ◽

Gram Negative

The aim of our study was to describe microorganisms which occur in the traditional Slovak cheese „Bryndza“. There were a total of 60 cheese samples collected from ten different farms during May 2019. The microbiota studies included the total bacterial count, coliforms, enterococci, lactic acid bacteria, yeasts and microscopic fungi. The total bacterial counts were cultivated on plate count agar at 30 °C in aerobic conditions, lactic acid bacteria on MRS at 37 °C in anaerobic conditions, coliform on VRBL and VRBG at 37 °C in aerobic condition, yeasts and microscopic fungi on MEA at 25 °C under aerobic condition. Gram-positive, Gram-negative and yeasts isolates were identified with MALDI-TOF MS Biotyper. Totally, a number of 1175 isolates of G-, G+ and yeast were identified with score higher than 2 and moulds. Escherichia coli and Stenotrophomonas maltophilia were the most frequently identified species of Gram-negative and Leuconostoc mesenteroides ssp. mesenteroides and Lactococcus lactis ssp. lactis from Gram-positive bacteria. Yarrowia lipolitica and Kluyveromyces lactis were the most distributed yeasts. Lactic acid bacteria group was represented by Lactobacillus, Lactococcus, Leuconostoc and Pediococcus. The most abundant genera of lactic acid bacteria were Lactobacillus with 11 species. This study describes the indigenous microbiota of the traditional ewe's milk cheeses from Slovakia.

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USE OF LACTIC ACID BACTERIA IN PEANUT SEED TREATMENT

JOURNAL OF TECHNOLOGY & INNOVATION ◽

10.26480/jtin.01.2021.20.22 ◽

2020 ◽

Vol 1 (1) ◽

pp. 20-22

Author(s):

Hoai Huong Nguyen ◽

Bich Tram Tran Le

Keyword(s):

Heat Treatment ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Seed Treatment ◽

Bacterial Count ◽

Positive Control ◽

Culture Broth ◽

Total Bacterial Count ◽

Conventional Agriculture ◽

Aspergillus Sp

Three lactic acid bacteria (LAB) strains, Lactobacillus sp. L5, Lactobacillus sp. L3, Lactobacillus sp. L2N, isolated from Vietnamese traditional Nem chua grew well in cabbage broth supplemented with 12 g/L glucose and 15 g/L peptone and showed inhibitory activity ranging from 40% to 44% against Aspergillus sp. CDP isolated from mould contaminated peanuts, while Daconil 75WP – a fungicide compounds – as a positive control showed only 26.9%. LAB strains also displayed Indole-acetic acid (IAA) production, P-solubilization and biofilm formation. Soaking seeds in separate cabbage based culture broth of three LAB strains with/without heat treatment and mixed culture broths at the ratio 1:1:1 with the total bacterial count 108cfu/mL exhibited the antifungal activity of mixed cultures in both cases with or without bacterial culture heat treatment. Soaking seeds in the same mixed bacterial cultures without heat treatment increased seed germination and vigor index, compared to the control seeds without any treatment and those treated with fungicide compounds. After 75 days of sowing the length and total fresh weight of LAB-treated peanut plants increased by 22.4 % and 99.6%, higher than that of Daconil treated ones with only 15.9% and 59.7% increment. Moreover, the fresh yield of peanut pegs increased 2.5 times, compared to those of untreated and Daconil treated seeds. This study suggested that seed treatment with LAB is a novel technology towards organic farming to replace fungicide used in conventional agriculture.

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78. A Study of the Quantitative Changes in the Microbiological Flora of Sweet-Cream Salted Butter of Good Keeping Quality when held at 15° F. for a Period of Two to Eight Months

Journal of Dairy Research ◽

10.1017/s002202990000100x ◽

1934 ◽

Vol 5 (2) ◽

pp. 137-143 ◽

Cited By ~ 5

Author(s):

M. Grimes ◽

A. J. Hennerty

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Titratable Acidity ◽

Bacterial Count ◽

Total Bacterial Count ◽

Noticeable Increase ◽

Keeping Quality ◽

Quantitative Changes ◽

Micro Organisms ◽

Microbiological Flora

1. Data, taken over a period of eight months, are presented, concerning the quantitative changes which take place in the microflora of sweet-cream salted cold-stored butter of good keeping quality.2. Tables showing the influence of varying periods of cold storage on the development of acidity, total bacterial count, yeasts, moulds, gelatin liquefying bacteria and types of micro-organisms in forty-nine churnings of butter cold stored at 15° F. are given.3. There was a slight increase in the titratable acidity.4. There was a noticeable increase of the yeast count, in many cases without apparently injuring the keeping quality.5. The numbers of Oidium lactis present tended to decrease.6. The following types of bacteria persisted in the sweet-cream salted butter in decreasing numbers: (a) various types of micrococci; (b) lactic acid bacteria of non-coagulating and acid coagulating types, including “slow” varieties of Str. lactis; (c) acid with coagulation and gas; (d) rennet digesting; (e) alkaline-forming; (f) alkaline digesting.

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Diversity of microorganisms in the traditional Slovak cheese

Potravinarstvo Slovak Journal of Food Sciences ◽

10.5219/1061 ◽

2019 ◽

Vol 13 (1) ◽

pp. 532-538

Author(s):

Miroslava Kačániová ◽

Simona Kunova ◽

Elena Horská ◽

Ľudmila Nagyová ◽

Czeslaw Puchalski ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Bacterial Count ◽

Raw Milk ◽

Lactobacillus Helveticus ◽

Coliform Bacteria ◽

Plate Count ◽

Total Bacterial Count ◽

Organoleptic Characteristics ◽

Microbiological Methods

The aim of the present study was to describe the microbial groups of the traditional Slovak cheese Parenica during rippening. The microbial group included the total bacterial count, coliform bacteria, enterococci, lactic acid bacteria, and microscopic filamentous fungi, which may affect the organoleptic characteristics of this product. A total of 42 cheese samples were collected from four different farms during three months. The total bacterial counts were cultivated on Plate count agar at 30 °C, lactic acid bacteria (LAB) on MRS, APT and MSE at 37 °C, coliform bacteria on VRBL at 37 °C. Gram-positive and Gram-negative isolates were identified by MALDI-TOF MS profiling. Bacillus sp. and Enterococcus faecium were the most frequently identified species of bacteria. Candida kefyr was the most distributed yeast according to microbiological methods. Lactic acid bacteria group was represented by Lactobacillus helveticus, L. jensenii, L. alimentarius, L. crispatus, L. curvatus, L. fermentum, L. suebicus, L. delbrueckii ssp. lactis, L. paracasei ssp. paracasei, Lactococcus lactis ssp. lactis, Leuconostoc lactis and Le. mesenteroides ssp. mesenteroides . This report describing the indigenous microbiota of the traditional raw milk cheeses from Slovakia. Our results provide useful information on occurrence of valuable microbial strain for the industrialization of producing of the traditional dairy products in Slovakia.

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EFFECT OF STORAGE TEMPERATURE ON THE MICROFLORA OF IRRADIATED AND NONIRRADIATED VACUUM-PACKAGED PETRALE SOLE FILLETS

Journal of Milk and Food Technology ◽

10.4315/0022-2747-31.8.231 ◽

1968 ◽

Vol 31 (8) ◽

pp. 231-236 ◽

Cited By ~ 6

Author(s):

Gretchen A. Pelroy ◽

John P. Seman

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Storage Temperature ◽

Radiation Treatment ◽

Bacterial Count ◽

Total Bacterial Count ◽

Polyethylene Bags ◽

Aerobic Flora ◽

Storage Temperatures ◽

Coagulase Positive Staphylococcus

Petrale sole fillets that were vacuum packaged in mylar-polyethylene bags were irradiated at 0.0, 0.1, 0.2, and 0.3 megarad and stored at 0.5, 3.3, 5.6, 7.8, 10.0, 15.6, and 22.2 C. The fish were monitored throughout storage for spoilage, total bacterial count, coliform count, enterococcus count, and the presence of coagulase-positive Staphylococcus. Generic changes in the aerobic flora were determined by the identification of nearly 14,000 microbial isolates. The predominant spoilage flora of the irradiated fish stored at all the temperatures were lactic acid bacteria. The predominant flora at the time of spoilage of the nonirradiated fish stored at 5.6 C and below was Pseudomonas. When the nonirradiated fish was stored above 5.6 C, the predominant spoilage flora was lactic acid bacteria. Coliforms and enterococci showed growth at the higher storage temperatures but were suppressed by the radiation treatment. No coagulase-positive Staphylococcus were found in any of the irradiated samples.

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The evolution of lactic acid bacteria community during the development of mature sourdough

Acta periodica technologica ◽

10.2298/apt0940111z ◽

2009 ◽

pp. 111-122

Author(s):

Tanja Zugic-Petrovic ◽

Natasa Jokovic ◽

Dragisa Savic

Keyword(s):

Principal Component Analysis ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Bacterial Population ◽

Principal Component ◽

Bacterial Count ◽

Phenotypic Characterization ◽

Statistical Techniques ◽

Total Bacterial Count ◽

Genus Lactobacillus

In order to follow the composition and changes in lactic acid bacteria (LAB) population of rye flour sourdough that was continuously propagated by a repeated inoculation, sixty-two strains of LAB were isolated and characterized. The LAB were the only bacteria detected, both at the end of the second propagation step and in the stage of mature sourdough (after two weeks of continuous daily refreshment). The stable ecological system in rye sourdough could be established from the second propagation step onward. The predominant genera of LAB during the development of sourdough were lactobacilli, which were grouped in eight clusters. Heterofermentative lactobacilli were in majority in both propagation step two and a mature sourdough participating 56% and 70% of total bacterial count, respectively. The identification based on a phenotypic characterization that was carried out by using a set of 36 tests, showed that the lactobacilli contained in the two sourdough steps did not clearly belong to any known species of the genus Lactobacillus. In addition, the structure of the bacterial population were monitored by two statistical techniques (Hierachical Cluster Analysis and Principal Component Analysis), being applied to phenotypical characteristics of the isolates.

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Galactooligosaccharide effects as prebiotic on intestinal microbiota of different fish species

RUDN Journal of Agronomy and Animal Industries ◽

10.22363/2312-797x-2019-14-3-266-278 ◽

2019 ◽

Vol 14 (3) ◽

pp. 266-278

Author(s):

Seyed Hossein Hoseinifar ◽

Hien Van Doan ◽

Ghasem Ashouri

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Gut Microbiota ◽

Intestinal Microbiota ◽

Bacterial Communities ◽

Bacterial Count ◽

Control Group ◽

Total Bacterial Count ◽

The Caspian Sea ◽

Caspian Roach

Manipulation of the gut microbiota toward potentially beneficial bacteria (probiotics) has beneficial effects on fish physiology and health. The effects of prebiotics on gut microbiota are species specific. The present study aimed at investigation of the effects of galactooligosaccharide (GOS) as prebiotic on intestinal microbiota of Caspian roach and Caspian white fish fingerlings. which are among the most economically valuable species in the Caspian Sea. The study was conducted in a completely randomized design with two set of experiment each of them include three treatments in triplicates in which 0 (control), 1 and 2% GOS were used in diet for 6 weeks. At the end of the period, changes in the intestinal microbiota, including total bacterial count, lactic acid count and lactic acid bacteria (LAB) levels and dominance of LAB in the intestinal microbiota, were measured by culture-based method. Dietary GOS had no significant effect on total bacterial count in both species (P < 0.05). The LAB levels in the intestinal microbiota in the treatments fed with prebiotics was significantly higher than the control group (P < 0.05). LAB bacteria showed the highest increase and dominance in treatments fed with 2% GOS. Also, the highest ratio of lactic acid bacteria to the total number of viable bacteria was observed in the treatment with 2% GOS treatment (P < 0.05). The results of this study indicated the possibility of alterations in the bacterial communities of Caspian roach and Caspian white fish fingerlings gut toward beneficial bacterial communities using GOS as prebiotic.

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