Contribution of natural milk culture to microbiota, safety and hygiene of raw milk cheese produced in alpine malga

Processing of alpine milk in malga farms is carried out under conditions that can favor contamination by coliforms, coagulase-positive staphylococci, or pathogens such as Listeria monocytogenes. With the aim to improve the hygienic characteristics and safety of cheese produced in four malga farms the use of lyophilized Natural Milk Culture prepared with selected strains was tested. Two cheesemaking tests were carried out in the same day always starting from the same milk: in the first case following the malga recipe that uses either Natural Whey Culture or without the addition of a starter, in the second one using a Natural Milk Culture. Cheesemaking were carried out in four malga farms located in the west area of Trentino region within the same week. For hygienic and safety evaluation, aerobic colony count, coagulase-positive staphylococci, Escherichia coli, staphylococcal toxins, Listeria monocytogenes , and Salmonella spp, pH and aw were determined in raw milk from evening and morning milking, curd in vat, curd after extraction and two months-ripened cheese. Pathogens or toxins, high values of coagulase- positive staphylococci and E. coli were not found in cheese samples. However, in the curd coagulase-positive staphylococci reached values almost of 5 Log CFU/g in the two malga without starter cultures. The use of Natural Milk Culture reduced E. coli counts. In addition, DNA was extracted from cheese samples and from Natural Milk Culture and the composition of the microbial community determined by Next Generation Sequencing method. The determination of cheese microbial communities demonstrated that the use of Natural Milk Culture exerted different effects in the different malga, in any case preserving bacterial biodiversity.

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Quality and safety of artisan cheese produced in the serrana region of Santa Catarina

Semina Ciências Agrárias ◽

10.5433/1679-0359.2017v38n2p739 ◽

2017 ◽

Vol 38 (2) ◽

pp. 739 ◽

Cited By ~ 2

Author(s):

Giane Helenita Pontarolo ◽

Fernanda Danielle Melo ◽

Caroline Lopes Martini ◽

Paula Wildemann ◽

Dileta Regina Moro Alessio ◽

...

Keyword(s):

Salt Content ◽

Raw Milk ◽

Good Manufacturing Practice ◽

Quality And Safety ◽

Salmonella Spp ◽

Santa Catarina ◽

Maturation Period ◽

E Coli ◽

Coagulase Positive Staphylococci ◽

Cheese Production

The serrano artisan cheese produced from raw milk of dairy cattle is a typical product of high-altitude farms in the states of Santa Catarina and Rio Grande do Sul. However, marketing of the cheeses occurs illegally because they lack the minimum maturation period required for cheese produced from raw milk. The production of artisan cheeses is required to follow strict hygiene standards. This study aimed to test the quality and safety of cheeses that were produced in 31 farms of the Serrana region in Santa Catarina after 14 and 28 days of maturation. Coliform count was measured at 35 °C, and presence of other microorganisms such as Escherichia coli, Staphylococcus, Listeria spp., and Salmonella spp. were also tested. Fat and protein percentages, acidity, salt content, and humidity were also evaluated. Data were subjected to statistical analyses using the SAS® software. After 14 and 28 days of maturation, 74.19% (23/31) and 64.52% (20/31) of samples, respectively, showed higher numbers of coliforms at 35 °C than those permissible by law. Higher than permissible numbers of E. coli were observed in 45.16% (14/31) and 48.39% (15/31) of the samples analyzed after 14 and 28 days of maturation, respectively. Coagulase-positive staphylococci values above 103 CFU/g were observed in 54.84% (17/31) and 51.61% (16/31) of cheese samples after 14 and 28 days of maturation, respectively. Contamination with Salmonella spp. was not detected. However, Listeria monocytogenes serovar 4b was isolated in 3.23% (1/31) and 6.45% (2/31) of samples after 14 and 28 days of maturation, respectively. The results of humidity tests classified the cheese samples into three categories: low, medium, and high humidity. Semi fat cheeses were predominant in both maturation periods, although the samples were classified in thin, semi fat, and fat cheeses. The main variations in the compositions of analyzed samples occurred for salt and acidity levels. The maturation process has not proven to be effective in reducing microbiological contamination to compliance levels. Considering the heterogeneity of the analyzed cheese samples, the frequency of non-conformities with respect to microorganisms and pathogens present in the samples, this study indicates the necessity to improve the Serrano artisan cheese production system through adoption of good manufacturing practice measures.

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Hygienic-health quality and microbiological hazard of clandestine Minas Frescal cheese commercialized in north Tocantins, Brazil

Semina Ciências Agrárias ◽

10.5433/1679-0359.2021v42n2p679 ◽

2021 ◽

Vol 42 (2) ◽

pp. 679-694

Author(s):

Monike da Silva Oliveira ◽

◽

Isac Gabriel Cunha dos Santos ◽

Bianca Pereira Dias ◽

Cristiane Alves Nascimento ◽

...

Keyword(s):

Listeria Monocytogenes ◽

Food Product ◽

Economic Loss ◽

Daily Basis ◽

Salmonella Spp ◽

High Count ◽

E Coli ◽

High Concentrations ◽

Sanitary Conditions ◽

Coagulase Positive Staphylococci

Cheese is a popular product that integrates the diet of the majority of the population, almost on a daily basis. It is rich in nutrients and, therefore, also an excellent substrate for the multiplication of microorganisms, including pathogens. The microbiological contamination of these products is highly relevant to the industry, resulting in an economic loss, and to public health, due to the risk of causing foodborne diseases. The aim of this study was to evaluate the hygienic-sanitary quality and the presence of bacterial pathogens in the clandestine Minas Frescal cheeses sold in the street open markets of Araguaína, TO, Brazil. Twenty-one samples were collected to evaluate the presence of total (TC) and thermotolerant (TTC) coliforms, Escherichia coli, and the pathotypes enteropathogenic E. coli (EPEC), and shiga toxin-producing E. coli (STEC) and enterohemorrhagic E. coli (EHEC), coagulase-positive staphylococci (CPS), Salmonella spp., and Listeria monocytogenes. The results showed that 100% of the cheese samples were in disagreement with the maximum standards of TC and TTC defined in the Brazilian legislation that regulates food quality control. In addition, 85.71% of the samples had values above the standard Brazilian maximum limit. In the study of diarrheagenic E. coli, 52.38%, 66.6%, and 4.76% of the samples were positive for EPEC, STEC, and EHEC, respectively, indicating fecal origin contamination of the samples and a potential consumer risk. No Salmonella spp. or Listeria monocytogenes were detected in these cheese samples. The high count of total and thermotolerant coliforms found in the samples demonstrates unsatisfactory sanitary conditions in the production, storage, and/or commercialization of this food product. The presence of EPEC, STEC, EHEC, and coagulase-positive staphylococci at high concentrations shows the health risk of the imminent consumption of Minas Frescal cheese.

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FoodSimplex as a Mean to Improve Portuguese Restaurants’ Goods Manufacturing Practices - Audit and Microbial Assessment

Current Nutrition & Food Science ◽

10.2174/1573401316999200403135832 ◽

2020 ◽

Vol 16 (9) ◽

pp. 1449-1458

Author(s):

Ana L. Baltazar ◽

Ana Ferreira ◽

Lara Manyes ◽

Jordi Mañes

Keyword(s):

Listeria Monocytogenes ◽

Food Safety ◽

Control Point ◽

Food Samples ◽

P Value ◽

Salmonella Spp ◽

E Coli ◽

Critical Control Point ◽

Audit Data ◽

Coagulase Positive Staphylococci

Background: The consumption of meals at resturants has increased mass catering establishments. Such food services may present several risk factors for foodborne diseases, which have a substantial negative impact on public health. The smallest business with no technical or financial support struggles to comply with food safety European Regulation. The aim of this four years study was to assess Good Manufacture Practices (GMP) in Portuguese restaurants applying a designed food safety methodology, FoodSimplex, through audit data to determine good manufacture practices, and microbiological sampling of the meals before and after its implementation, by food groups according to their risk. Methods: FoodSimplex is a combination of four stages methodology, based on Hazards Analysis and Critical Control Point (HACCP), combined with technical-functional and food safety audits, with pretested checklist, training and microbial analysis (Mesophylic bacteria, Listeria monocytogenes, E. coli, Coagulase-positive staphylococci and Salmonella spp) of the meals served. Results: Results of the food safety audit for GMP parameters showed a general improvement with 80% compliance with the checklist subitems. The ready-to-eat food samples presented, regarding the total mesophilic aerobes count, a statistical significant change to acceptable and satisfactory condition (p-value= 0.029). 100% compliance, with acceptable and satisfactory results was observed for Listeria monocytogenes (p-value= 0.180) and for E. coli, coagulase-positive Staphylococci and Salmonella spp., all the food samples presented satisfactory results in the study (100%). Conclusion: At the end of the investigation period, a decrease in bacterial populations in food samples was observed with an improvement of the GMP audit data which indicated that the FoodSimplex methodology improved the food safety status of these establishments.

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Foodborne Pathogen Assessment in Raw Milk Cheeses

International Journal of Food Science ◽

10.1155/2020/3616713 ◽

2020 ◽

Vol 2020 ◽

pp. 1-5

Author(s):

Nicola Costanzo ◽

Carlotta Ceniti ◽

Adriano Santoro ◽

Maria Teresa Clausi ◽

Francesco Casalinuovo

Keyword(s):

Listeria Monocytogenes ◽

Foodborne Pathogens ◽

Foodborne Pathogen ◽

Bacterial Count ◽

Raw Milk ◽

Good Manufacturing Practice ◽

Staphylococcal Enterotoxin ◽

Total Bacterial Count ◽

E Coli ◽

Coagulase Positive Staphylococci

General hygienic parameters and selected foodborne pathogens in raw milk cheeses at the retail level were evaluated. A total of 245 raw milk cheese samples were analysed for total bacterial count, Enterobacteriaceae, E. coli, Salmonella spp., Listeria monocytogenes, coagulase-positive Staphylococci, and staphylococcal enterotoxin. Results showed only 3 samples that were not compliant with European rules on staphylococcal enterotoxin, but coagulase-positive Staphylococci were evidenced in all samples tested. Salmonella spp. and Listeria monocytogenes were never detected whereas E. coli was evidenced in 20 samples. Results suggest a need for improvement of good manufacturing practice and milking operation.

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Behaviour of Listeria monocytogenes and Escherichia coli O157:H7 during the cheese making of traditional raw-milk cheeses from Italian Alps

Italian Journal of Food Safety ◽

10.4081/ijfs.2015.4585 ◽

2015 ◽

Vol 4 (2) ◽

Cited By ~ 1

Author(s):

Elena Cosciani-Cunico ◽

Elena Dalzini ◽

Stefania Ducoli ◽

Chiara Sfameni ◽

Barbara Bertasi ◽

...

Keyword(s):

Escherichia Coli ◽

Listeria Monocytogenes ◽

Raw Milk ◽

Starter Cultures ◽

Cow Milk ◽

Italian Alps ◽

Cheese Making ◽

E Coli ◽

Food Borne ◽

First Time

The behaviour of Listeria monocytogenes and Escherichia coli O157:H7 was studied during the manufacture and ripening of two traditional Italian Alps cheeses. Each cheese type was manufactured in a pilot plan from raw cow milk (without the addition of starter cultures) artificially inoculated with L. monocytogenes and E. coli O157:H7 to a final concentration of about 4 log CFU/mL. The pathogens were enumerated throughout the cheese making and ripening processes to study their behaviour. When the milk was inoculated with 4 Log CFU/mL, the pathogens counts increased in the first time during the manufacturing process and then remained constant, until the end of ripening, or decreased significantly. Results indicate that the environment and nature of food borne pathogens affected the concentration of the bacteria during the manufacturing and ripening process. Thus, the presence of low cells numbers of L. monocytogenes and E. coli O157:H7 in milk destined for the production of raw milk cheeses characterized by a cooking of the curd less than 48°C can constitute a hazard for the consumer.

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“Burrata di Andria” PGI Cheese: Physicochemical and Microbiological Features

Foods ◽

10.3390/foods9111694 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1694

Author(s):

Alessandro Di Cerbo ◽

Dino Miraglia ◽

Leonardo Marino ◽

Roberta Stocchi ◽

Anna Rita Loschi ◽

...

Keyword(s):

Food Production ◽

Raw Milk ◽

Viable Count ◽

Salmonella Spp ◽

European Regulation ◽

E Coli ◽

Nonpathogenic Strain ◽

Industrial Food Production ◽

Opposite Situation ◽

Coagulase Positive Staphylococci

In the last century, the exponential increase of industrial food production led to the disappearance of “Italian traditional niche products”. However, national regulations allowed the preservation of several of these products, including the burrata cheese. Twenty-one samples from three different batches of “Burrata di Andria” Protected Geographical Indication (PGI) were purchased from dairy factories of the PGI consortium. Moisture value of PGI Burrata cheese was significantly higher than that before the PGI release. Moreover, a significantly lower NaCl value was detected in PGI raw milk Burrata cheeses with respect to non-PGI ones, while an opposite situation was detected in pasteurized milk Burrata cheeses. As for pH, in all PGI products lower values were observed with respect to non-PGI products, which resulted significant only in pasteurized ones. No Salmonella spp., Listeria monocytogenes, and Bacillus cereus were detected, while nine samples were positive for a nonpathogenic strain of Yersinia enterocolitica. Total viable count (TVC) and Escherichia coli resulted significantly lower in pasteurized than in raw milk PGI Burrata cheese samples. Although samples analyzed can be considered microbiologically safe, these were borderline and/or unsatisfactory for E. Coli and coagulase-positive staphylococci (CPS) according to process hygiene criteria established by European regulation. Therefore, different strategies should be adopted to improve products hygiene in the considered dairy factories.

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Some Chemical and Bacteriological Characteristics of Regional Cheeses from Asturias, Spain

Journal of Food Protection ◽

10.4315/0362-028x-59.5.509 ◽

1996 ◽

Vol 59 (5) ◽

pp. 509-515 ◽

Cited By ~ 17

Author(s):

ABELARDO MARGOLLES ◽

ANA RODRIGUEZ ◽

CLARA G. de los REYES-GAVILAN

Keyword(s):

Listeria Monocytogenes ◽

Listeria Innocua ◽

Chemical Characteristics ◽

Salmonella Spp ◽

Cheese Making ◽

Ph Values ◽

Plate Counts ◽

Coagulase Positive Staphylococci ◽

Enrichment Methods

One hundred and one samples of six representative short-ripened cheeses (five homemade and one industrially manufactured) were collected over 1 year in several supermarkets in Asturias and analyzed for mesophilic plate counts, coliforms, enterobacteria, coagulase-positive staphylococci, the presence of species of Salmonella and Listeria, pH, moisture, NaCl, and aw. Chemical characteristics varied, largely depending on the type of cheese. The percentages of moisture and NaCl ranged from 36.11 to 48.91 and from 1.16 to 2.08 respectively. The aw values were between 0.95 and 0.99. Acidification was quite efficient, all cheeses having mean pH values between 4.56 and 5.39. None of the samples yielded Salmonella spp. Coagulase-positive staphylococci were detected in two cheeses, in one reaching levels up to 106 CFU/g. Listeria spp. contaminated 11.8% of the cheeses, with Listeria monocytogenes isolated from 8.91 % and Listeria innocua from 4.95% of the samples. The distribution of Listeria spp. varied largely depending on the type of cheese: 41% of the samples contaminated with L. monocytogeneswere obtained from one type of cheese which had the lowest pH and NaCl values and the highest aw and moisture levels of the cheeses analyzed. However, L. monocytogenes was absent from another type of cheese, which showed intermediate chemical characteristics. High levels of coliforms and enterobacteria (4 to 5 log CFU/ml) were detected in the five homemade cheeses and were statistically associated with the presence of Listeria spp. and L. monocytogenes. Cold enrichment was unsuccessful for the recovery of Listeria spp. from the cheeses analyzed, while a combination of different enrichment methods resulted in the best procedure for detecting all positive samples. This study shows that L. monocytogenes and coagulase-positive staphylococci are present in short-ripened cheeses consumed in Asturias. Adequate measures to prevent contamination during cheese making will probably result in safer products.

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Growth inhibition of foodborne pathogens in camel milk: Staphylococcus aureus, Listeria monocytogenes, Salmonella spp. and E. coli O157:H7

Czech Journal of Food Sciences ◽

10.17221/84/2017-cjfs ◽

2017 ◽

Vol 35 (No. 4) ◽

pp. 311-320 ◽

Cited By ~ 3

Author(s):

Abusheliabi Aisha ◽

Al-Holy Murad A ◽

Al-Rumaithi Hind ◽

Al-Khaldi Sufian ◽

Al-Nabulsi Anas A ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Listeria Monocytogenes ◽

Growth Inhibition ◽

Foodborne Pathogens ◽

Bovine Milk ◽

Growth Patterns ◽

Camel Milk ◽

Salmonella Spp ◽

E Coli ◽

Milk Samples

The growth behaviour of foodborne pathogens (Staphylococcus aureus, Listeria monocytogenes, E. coli O157:H7 and Salmonella spp.) was investigated in pasteurised camel milk and compared with pasteurised bovine milk at different incubation temperatures. This study also aimed to compare the growth patterns of these four foodborne pathogens in pasteurised and raw camel milk. Pasteurised or raw camel milk and pasteurised bovine milk were separately inoculated with a cocktail of three strains of each foodborne pathogen. The inoculated milk samples were incubated at 10, 25, and 37°C. The total bacterial count (TBC) in raw milk and the total thermoduric bacteria count (TDB) in pasteurised milk samples were monitored. Greater growth inhibition rates of four pathogens were obtained for the pasteurised camel milk compared to the pasteurised bovine milk. Raw and pasteurised camel milk exerted bacteriostatic effect against all tested pathogens, particularly for the first 8 h of incubation in milk at the different temperatures. Pasteurised camel milk exerted an inhibitory activity that was equivalent to that of raw camel milk.

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