scholarly journals Quantitative Microbiological Analysis of Artisanal Stretched Cheese Manufacture

2021 ◽  
Author(s):  
Veronika Lehotová ◽  
Veronika Antálková ◽  
Alžbeta Medveďová ◽  
Ľubomír Valík
Keyword(s):  
Early Stage ◽  
Storage Period ◽  
Coliform Bacteria ◽  
Microbiological Analysis ◽  
E Coli ◽  
Log Reduction ◽  
Milk Coagulation ◽  
Entire Storage Period ◽  
Stretching Process ◽  
Cheese Production

To evaluate the behaviour of the relevant microbial populations during stretched cheese production, the quantitative microbiological analysis was performed during the critical steps of the preparation. The obtained data distributions proved statistically significant increases in all indicators, on average by 4.55 ± 0.64 log CFU/g of presumptive lactococci counts, 4.06 ±0.61 of lactobacilli, 1.53 ± 0.57 log CFU/g of coliforms, 2.42 ± 0.67 log CFU/g of Escherichia coli, 1.53 ± 0.75 log CFU/g of yeasts and moulds, and 0.99 ± 0.27 log CFU/g of presumptive Staphylococcus aureus, from the early stage of milk coagulation until curd ripening (0–24 h). The following steaming/stretching process caused reductions in viable counts with the most significant inactivation effect on coliform bacteria, including E. coli (-4.0 ± 1.0 log CFU/g). Total viable counts and yeasts and moulds showed 2 and almost 3 log reduction (-2.2 ± 1.1 log CFU/g and -2.6 ± 0.9 log CFU/g), respectively. The lowest decreases in presumptive S. aureus counts were estimated at the level of -1.50 ± 0.64 log CFU/g. The counts of yeasts and moulds showed the best indicatory function during the entire storage period of vacuum-packaged cheeses at 6 °C.

scholarly journals Quantitative Microbiological Analysis of Artisanal Stretched Cheese Manufacture

2021 ◽  
Vol 11 (6) ◽  
pp. 2680
Author(s):  
Veronika Lehotová ◽  
Veronika Antálková ◽  
Alžbeta Medveďová ◽  
Ľubomír Valík
Keyword(s):  
Early Stage ◽  
Storage Period ◽  
Coliform Bacteria ◽  
Microbiological Analysis ◽  
E Coli ◽  
Log Reduction ◽  
Milk Coagulation ◽  
Yeasts And Molds ◽  
Entire Storage Period ◽  
Cheese Production

To evaluate the behavior of the relevant microbial populations during stretched cheese production, quantitative microbiological analysis was performed during the critical steps of the preparation. The obtained data distributions proved statistically significant increases in all indicators, on average by 4.55 ± 0.64 log CFU/g of presumptive lactococci counts, 4.06 ± 0.61 of lactobacilli, 1.53 ± 0.57 log CFU/g of coliforms, 2.42 ± 0.67 log CFU/g of Escherichia coli, 1.53 ± 0.75 log CFU/g of yeasts and molds, and 0.99 ± 0.27 log CFU/g of presumptive Staphylococcus aureus, from the early stage of milk coagulation until curd ripening (0–24 h). The following steaming/stretching process caused reductions in viable counts with the most significant inactivation effect on coliform bacteria, including E. coli (−4.0 ± 1.0 log CFU/g). Total viable counts and yeasts and molds showed 2 and almost 3 log reduction (−2.2 ± 1.1 log CFU/g and −2.6 ± 0.9 log CFU/g), respectively. The lowest decreases in presumptive S. aureus counts were estimated at the level of −1.50 ± 0.64 log CFU/g. The counts of yeasts and molds showed the best indicatory function during the entire storage period of vacuum-packaged cheeses at 6 °C.

Inactivation of Saccharomyces cerevisiae and Polyphenoloxidase in Mango Nectar Treated with UV Light

2006 ◽  
Vol 69 (2) ◽  
pp. 362-368 ◽  
Author(s):  
JOSÉ A. GUERRERO-BELTRÉN ◽  
GUSTAVO V. BARBOSA-CÉNOVAS
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Uv Light ◽  
Storage Period ◽  
Microbial Load ◽  
Microbial Count ◽  
Uv Treatment ◽  
Log Reduction ◽  
First Order Kinetics ◽  
Yellow Orange ◽  
Entire Storage Period

Fresh mango nectar was processed by UV light at five flow rates (0.073 to 0.451 liter/min) and five UV light doses (75 to 450 kJ/m2) to evaluate total microbial load, Saccharomyces cerevisiae survival, and polyphenoloxidase activity. UV systems containing an inner mercury lamp (254 nm) each with intensity of 25 mW/cm2 were used as germicidal sources. In addition, mango nectar was treated for 15 min at 0.073 and 0.451 liter/min, stored at 3°C, and evaluated periodically for total microbial count, yeast count, color, and polyphenoloxidase activity. The first-order kinetics modeling found that DUV-values in mango nectar ranged from 27.9 to 10.9 min (R2 > 0.950) and 26.0 to 11.8 min (R2 > 0.962) for total microbial count and yeast count, respectively. The maximum log reduction (CFU per milliliter) was 2.71 and 2.94 for total microbial count and yeast count, respectively, after 30 min of UV treatment at 0.451 liter/min. DUV-values ranging from 156 to 204 min were observed for polyphenoloxidase activity. The remaining polyphenoloxidase activity after 30 min of UV treatment at 0.451 liter/min was 19 ± 4%. Initial microbial load and yeast in stored mango nectar were reduced in the range 2.86 to 3.41 and 1.82 to 1.97 log (CFU/ml) cycles, respectively. No substantial microbial growth was observed prior to 20 days of storage. Averages of 1,055 ± 32, 803 ± 32, and 710 ± 37 enzyme activity units were observed in mango nectar UV processed at 0, 0.073, and 0.451 liter/min, respectively, during the entire storage period. However, mango nectar treated at 0.073 and 0.451 liter/min maintained a yellow and yellow-orange color, respectively, after 26 days of storage.

Antimicrobial Effects of Alginate-Based Film Containing Essential Oils for the Preservation of Whole Beef Muscle

2006 ◽  
Vol 69 (10) ◽  
pp. 2364-2369 ◽  
Author(s):  
MOUNIA OUSSALAH ◽  
STÉPHANE CAILLET ◽  
STÉPHANE SALMIÉRI ◽  
LINDA SAUCIER ◽  
MONIQUE LACROIX
Keyword(s):  
Essential Oils ◽  
Salmonella Typhimurium ◽  
Storage Period ◽  
Edible Films ◽  
Total Phenolic ◽  
Microbiological Analysis ◽  
Active Compounds ◽  
E Coli ◽  
Beef Muscle

Alginate-based edible films containing 1% (wt/vol) essential oils of Spanish oregano, Chinese cinnamon, or savory were immersed in 2% (wt/vol) or 20% (wt/vol) CaCl2 solution and then applied to beef muscle slices to control the growth of Escherichia coli O157:H7 and Salmonella Typhimurium. Whole beef muscle surfaces were inoculated with one of these strains at 103 CFU/cm2. During the 5 days of storage, samples of meat were obtained periodically for microbiological analysis. The availability of active compounds from essential oils present in films was evaluated by determination of total phenolic compounds for oregano- and savory-based films and of total aldehydes for cinnamon-based films during storage. After 5 days of storage, films containing oregano or cinnamon essential oils were the most effective against Salmonella Typhimurium regardless of the type of pretreatment used (2 or 20% CaCl2). During the same period, meat inoculated with E. coli O157:H7 and coated with films treated with 2% CaCl2 had significantly fewer bacteria (P ≤ 0.05) when oregano-based films were used than when cinnamon- and savory-based films were used. The E. coli O157:H7 concentration was higher at the end of the storage period when films were pretreated with 20% CaCl2. Evaluation of the active compounds in films revealed that availability in oregano-and savory-based films was significantly more important (P ≤ 0.05) than that in cinnamon-based films regardless of the type of pretreatment used (2 or 20% CaCl2). At the end of storage, release rates of 40, 60, and 77% were noted in oregano-, savory-, and cinnamon-based films in 2% CaCl2 and rates of 65, 62, and 90% were noted in the same films in 20% CaCl2.

Survival of Shiga Toxin–Producing Escherichia coli in Various Wild Animal Feces That May Contaminate Produce

2020 ◽  
Vol 83 (8) ◽  
pp. 1420-1429
Author(s):  
ZEYNAL TOPALCENGIZ ◽  
SAHARUETAI JEAMSRIPONG ◽  
PATRICK M. SPANNINGER ◽  
ANIL K. PERSAD ◽  
FEI WANG ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Storage Period ◽  
Wild Animal ◽  
E Coli ◽  
Similar Survival ◽  
Entire Storage Period ◽  
Food Safety Risk ◽  
Animal Feces ◽  
Feral Pig

ABSTRACT Domestic and wild animal intrusions are identified as a food safety risk during fresh produce production. The purpose of this study was to evaluate the survival of Shiga toxin–producing Escherichia coli (STEC) in cattle, feral pig, waterfowl, deer, and raccoon feces from sources in California, Delaware, Florida, and Ohio. Fecal samples were inoculated with a cocktail of rifampin-resistant STEC serotypes (O103, O104, O111, O145, and O157) (104 to 106 CFU/g of feces). Inoculated feces were held at ambient temperature. Populations of surviving cells were monitored throughout 1 year (364 days), with viable populations being enumerated by spread plating and enrichment when the bacteria were no longer detected by plating. Representative colonies were collected at various time intervals based on availability from different locations to determine the persistence of surviving STEC serotypes. Over the 364-day storage period, similar survival trends were observed for each type of animal feces from all states except for cattle and deer feces from Ohio. STEC populations remained the highest in cattle and deer feces from all states between days 28 and 364, except for those from Ohio. Feral pig, waterfowl, and raccoon feces had populations of STEC of <1.0 log CFU/g starting from day 112 in feces from all states. E. coli O103 and O104 were the predominant serotypes throughout the entire storage period in feces from all animals and from all states. The survival of both O157 and non-O157 STEC strains in domesticated and wild animal feces indicates a potential risk of contamination from animal intrusion. HIGHLIGHTS

scholarly journals The Role of Probiotic Bacteria on Microbiological and Acceptability of Sudanese White Soft Cheese

2021 ◽  
Vol 04 (05) ◽  
Author(s):  
Alwaleed Ibrahim Dafalla ◽  
Keyword(s):  
Pathogenic Bacteria ◽  
Storage Period ◽  
Bifidobacterium Bifidum ◽  
Probiotic Bacteria ◽  
Coliform Bacteria ◽  
Microbiological Analysis ◽  
Overall Acceptability ◽  
Soft Cheese ◽  
Microbial Analysis

The objectives of this investigation is to study the effect of three types of probiotic bacteria (Lactobacilus rhamnosus, Lactobacillus casei, Bifidobacterium bifidum) on the microbiological and acceptability of Sudanese white soft cheese during storage period 0, 15, 30, 45 and 60 days. Microbiological analysis revealed that, the highest count of probiotic bacteria (87x108cfu/g) was obtained by sample containing L.rhamnosus and the lowest (39x106 cfu/g) by sample containing B.bifidum, while the sample containing L.casei ranked in intermediate position. Storage period affected the total probiotic bacteria count, the highest count at 2 weeks for L.casei and B.bfidum and after 4 weeks for L.rhamnosus, while the lowest at the end. The microbial analysis did not detect any pathogenic bacteria (coliform bacteria, salmonella and staphylococcus aureus) or yeast and molds. The sensory evaluation quality revealed that the cheese containing L.rhamnosus gave the best appearance, texture, flavour and overall acceptability, followed by L.casei and B.bifidum compared with the control samples. The storage period significantly (p≤0.05) affected the acceptability of the cheese, where the highest score was obtained at day 30 and the lowest at the beginning of the storage. The study recommends further studies and tests to improve the quality of the Sudanese white soft cheese treated by probiotic bacteria.

scholarly journals Physical-Chemical and Microbiological Analysis of the Steaming Brine Used in the Fabrication of Pressed Cheeses

1970 ◽  
Vol 66 (2) ◽  
Author(s):  
Dorin ŢIBULCĂ ◽  
Aurora ŢIBULCĂ ◽  
Mirela JIMBOREAN ◽  
Cornel LASLO ◽  
Delia TRUŢĂ
Keyword(s):  
Salt Concentration ◽  
Coliform Bacteria ◽  
Microbiological Analysis ◽  
Salmonella Spp ◽  
E Coli ◽  
Milk Processing ◽  
Physical Chemical ◽  
Microbiological Aspects ◽  
Made In

The investigations had as aim to study the physical-chemical aspects (salt concentration and temperature) and microbiological aspects (TNG, coliform bacteria, E. coli, Stqfilococcus aureus c.p. and Salmonella spp.) of the steaming brine in the fabrication of the pressed cheeses Dalia, Rucăr, Penteleu. The investigations were made in five milk processing units in cheeses with steamed paste.

scholarly journals Influence of antioxidative and antibacterial activity of sage aqueous extract and chitosan formulation on chicken burger quality

2021 ◽  
Vol 77 (06) ◽  
pp. 6531-2021
Author(s):  
ANETA CEGIEŁKA ◽  
ELŻBIETA HAĆ-SZYMAŃCZUK ◽  
KATARZYNA FRĄCZKIEWICZ ◽  
MARTA CHMIEL
Keyword(s):  
Antibacterial Activity ◽  
Aqueous Extract ◽  
Meat Products ◽  
Storage Period ◽  
Coliform Bacteria ◽  
Psychrotrophic Bacteria ◽  
Brochothrix Thermosphacta ◽  
Salvia Officinalis L ◽  
Entire Storage Period ◽  
Microbiological Analyses

The aim of the present study was to assess the antioxidative and antibacterial activity of sage (Salvia officinalis L.) aqueous extract and chitosan formulation in chicken burgers during storage. Four burger treatments were prepared: C – without sage extract and chitosan formulation, S – with 2.0% of sage extract, CH – with 1.0% of chitosan formulation, and SCH – with 2.0% of sage extract and 1.0% of chitosan formulation. On the production day, the chemical composition of poultry burgers was analyzed. After 0, 7 and 14 days of storage in burgers, the advancement of the lipid oxidation process was assessed and microbiological analyses were performed. Microbiological analyses included the determination of the total count of mesophilic aerobic microorganisms and that of psychrotrophic bacteria, count of coliform bacteria, count of Pseudomonas, and count of lactic acid bacteria. One of the tested groups of bacteria was Brochothrix thermosphacta, which can cause spoilage of packaged meat products stored under refrigeration temperature. It has been found that aqueous sage extract had significantly (p <0.05) the best antioxidative effect compared to chitosan and the combination of sage extract and chitosan formulation in chicken burgers during the entire storage period. Both aqueous sage extract and chitosan formulation exhibited antibacterial activity in chicken burgers, although the efficiency of growth inhibition differed between the tested bacteria groups. After 14 days of storage of burgers, the significantly (p <0.05) lowest number of mesophilic aerobic microorganisms, Pseudomonas spp., and B. thermosphacta were found in burgers with the combination of sage extract and chitosan formulation.

Effects of Consumption of Probiotic Powder Containing Lactobacillus Plantarum Dad-13 on Fecal Bacterial Population in School-Age Children in Indonesia

2019 ◽  
Vol 14 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Banin Maghfirotin Marta ◽  
Utami Tyas ◽  
Cahyanto Muhammad Nur ◽  
Widada Jaka ◽  
Rahayu Endang Sutriswati
Keyword(s):  
Placebo Group ◽  
Gut Microbiota ◽  
Lactobacillus Plantarum ◽  
Coliform Bacteria ◽  
School Age Children ◽  
Controlled Study ◽  
School Age ◽  
Double Blind ◽  
Probiotic Group ◽  
E Coli

Consumption of probiotics is known to influence the gut microbiota. The aim of this study was to assess the effect of probiotic powder containing Lactobacillus plantarum Dad-13 on bacterial composition in the gut by examining fecal samples of school-age children in Yogyakarta, Indonesia. This is a randomized, double-blind, placebo-controlled study. A total of 40 healthy subjects were recruited for this study and were divided into two groups: placebo group and probiotic group. The placebo group consumed skim milk and the probiotic group consumed probiotic powder containing L. plantarum Dad-13 (2 × 109 CFU/g) for 65 days. The results showed that placebo intake had no significant effect on gut microbiota; however, probiotic caused a significant increase in L. plantarum and Lactobacillus population, while decreasing the population of E. coli and non-E. coli coliform bacteria by 55% and 75%, respectively and Bifidobacteria count did not change significantly. The study concluded that consumption of probiotic powder L. plantarum Dad-13 could increase propionic acid thereby decreasing the gut pH which has an effect on the microbial population.

scholarly journals Quality of beef diaphragm meat in naturally occurring Sarcocystic infection in cattle

2018 ◽  
Vol 36 (No. 5) ◽  
pp. 378-385
Author(s):  
Vytautas Januskevicius ◽  
Grazina Januskeviciene ◽  
Gintare Zaborskiene
Keyword(s):  
Meat Quality ◽  
Harmful Effect ◽  
Coliform Bacteria ◽  
E Coli ◽  
Noticeable Increase ◽  
Physico Chemical ◽  
Infected Meat ◽  
Technological Quality ◽  
Meat Samples

The aim of this study was to investigate the possible harmful effect of Sarcocystis parasites on bovine diaphragm meat quality. Meat samples were collected from 120 bulls aged 20–24 months. Meat quality was investigated using microbiological and physico-chemical (RP-HPLC, GC) methods 48 hours after slaughter. Sarcocystis infection was associated with increased fat content, lightness L* and drip loss, and decreased ash and protein percentages. Infection also had a significant effect on the amount of amino acids (AAs), which slowly decreased as the number of sarcocysts increased. The total amount of AAs correlated with glutamic acid content (R = 0.966, P &lt; 0.05). Heavily infected samples contained significantly lower amounts of putrescine, histamine, spermine and spermidine (P &lt; 0.05) and<br /> a noticeable increase in the total count of aerobic microorganisms, but no change in the numbers of E. coli and coliform bacteria in comparison with no infected samples. Sarcocysts in beef diaphragms did not cause serious changes in the technological quality of the meat, but the biological quality of infected meat was reduced.  

scholarly journals High-throughput microbioreactor provides a capable tool for early stage bioprocess development

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mathias Fink ◽  
Monika Cserjan-Puschmann ◽  
Daniela Reinisch ◽  
Gerald Striedner
Keyword(s):  
High Throughput ◽  
Process Development ◽  
Early Stage ◽  
Explanatory Power ◽  
Batch Mode ◽  
E Coli ◽  
Speed Up ◽  
Bioreactor System ◽  
Cell Densities ◽  
Microbial Systems

AbstractTremendous advancements in cell and protein engineering methodologies and bioinformatics have led to a vast increase in bacterial production clones and recombinant protein variants to be screened and evaluated. Consequently, an urgent need exists for efficient high-throughput (HTP) screening approaches to improve the efficiency in early process development as a basis to speed-up all subsequent steps in the course of process design and engineering. In this study, we selected the BioLector micro-bioreactor (µ-bioreactor) system as an HTP cultivation platform to screen E. coli expression clones producing representative protein candidates for biopharmaceutical applications. We evaluated the extent to which generated clones and condition screening results were transferable and comparable to results from fully controlled bioreactor systems operated in fed-batch mode at moderate or high cell densities. Direct comparison of 22 different production clones showed great transferability. We observed the same growth and expression characteristics, and identical clone rankings except one host-Fab-leader combination. This outcome demonstrates the explanatory power of HTP µ-bioreactor data and the suitability of this platform as a screening tool in upstream development of microbial systems. Fast, reliable, and transferable screening data significantly reduce experiments in fully controlled bioreactor systems and accelerate process development at lower cost.

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