Patrizia Tucci - Academia.edu (original) (raw)

Papers by Patrizia Tucci

Research paper thumbnail of Recent Trends of Antibiotic Resistance in Staphylococcus aureus Causing Clinical Mastitis in Dairy Herds in Abruzzo and Molise Regions, Italy

This study was aimed to examine the recent trends of antibiotic resistance (AR) prevalence in Sta... more This study was aimed to examine the recent trends of antibiotic resistance (AR) prevalence in Staphylococcus aureus isolated from milk of animals with clinical mastitis in areas of the Abruzzo and Molise regions in central Italy. Fifty-four S. aureus isolates could be obtained from routine testing for clinical mastitis agents carried out in the author institution in years 2021 and 2022. These were analyzed for phenotypic resistance to eight antibiotics recommended for testing by European norms and belonging to the antibiotic classes used for mastitis treatment in milk producing animals. Moreover, the presence of 14 transferable genetic determinants encoding resistance to the same antibiotics was analyzed by qPCR tests developed in this study. Phenotypic resistance to non-β-lactams was infrequent, with only one 2022 isolate resistant to clindamycin. However, low level resistance to the β-lactam cefoxitin was observed in 59.2% isolates in both years making these isolates classifiable ...

Research paper thumbnail of Survival rate of Escherichia coli O157 in artificially contaminated raw and thermized ewe milk in different Pecorino cheese production processes

International Journal of Food Microbiology

Pecorino is a typical Italian cheese, mostly produced in central and southern Italy regions using... more Pecorino is a typical Italian cheese, mostly produced in central and southern Italy regions using ewe raw milk and following traditional procedures. The use of raw milk constitutes a risk linked to the potential survival or multiplication of pathogenic microorganisms, as Shiga toxin-producing Escherichia coli (STEC). The aim of this study was to compare different Italian traditional Pecorino production methods to determine if there were any phases that could influence the Escherichia coli O157 survival rate, but also if they could negatively influence lactic acid bacteria survival rate, during the phases of production and ripening. Therefore batches of Pecorino cheese were prepared using different production methods, representing the real and typical cheese production in southern and central Italy regions: 1) heating the milk at 37 °C for about 40 min before curding, 2) heating the milk at 60 °C (thermization) for 13 min, so that the alkaline phosphatase reaction is still positive before curding, 3) cooking curd at 41 °C and 4) at 45 °C, both for 5 min. Our results demonstrated that traditional milk treatments different from pasteurization can help but do not eliminate serious microbiological treats, as E. coli O157, especially if the raw milk is heavily contaminated. The heat treatment at 60 °C applied to raw milk was able to decrease the concentration of E. coli O157 of 1.7 log10CFU/ml and, according to the inactivation slope, it would be further reduced prolonging the heating treatment. The results obtained also showed that, during the Pecorino cheese ripening, E. coli O157 was always enumerable for 60 days, remaining detectable after 90 days of ripening.

Research paper thumbnail of Variability of the microbiota in traditional Caciocavallo, Scamorza and Caciotta cheeses manufactured with raw milk and natural cultures

International Journal of Dairy Technology

Research paper thumbnail of Characterization of Lactic Acid Bacteria in Pecorino DI Farindola Cheese and Manufacturing with a Lacticaseibacillus Paracasei Autochthonous Culture

This study focused on the characterization of lactic acid bacteria (LAB) in a renowned traditiona... more This study focused on the characterization of lactic acid bacteria (LAB) in a renowned traditional Italian cheese, Pecorino di Farindola, to select an autochthonous culture and investigate its po-tential for the improvement of safety and functional properties. Two hundred and six LAB isolated throughout production and maturation from nine cheese lots of three farms were identified by 16S rRNA gene sequencing and tested for the presence of genes encoding virulence factors, vancomycin resistance (for enterococci), biogenic amines (BAs) and bacteriocin production, for antimicrobial activity, and for the capacity to survive in the gastro-intestinal tract (GIT) based on tolerance to low pH and bile salts and adhesion to CaCo-2 cells. A Lacticaseibacillus paracasei isolate was used in cheese making and determined a decline of spiked Listeria monocytogenes and Escherichia coli O157 faster than in control cheese. The autochthonous bacterial groups were numerically unaffected, apart from lac...

Research paper thumbnail of A new procedure for surface contamination of food products using absorbent paper

Journal of Food Safety, 2018

A new method was developed for artificial contamination of food products during challenge test st... more A new method was developed for artificial contamination of food products during challenge test studies, in products where superficial contamination is needed. Rinds of Gorgonzola cheese wheels were divided into quarters and then squares with 12 cm of side and contaminated with absorbent paper soaked with a bacterial suspension of Listeria monocytogenes left in contact with the surface of the blue-veined cheese, in order to achieve homogenous contamination of the whole surface. To verify the performance of the method of contamination, after 24 hr L. monocytogenes was enumerated to evaluate surface contamination. With the method described, an average concentration of about 5 log 10 cfu/cm 2 or MPN/cm 2 was obtained starting from a contaminated suspension of 8 log 10 cfu/ml. The homogeneity of the contamination was demonstrated by the application of statistical tests. Practical applications Challenge tests are carried out to simulate contaminations as they happen during the processing and aging of cheeses, cured meats or ready-to-eat foods, for cross contamination studies, for applications of predictive microbiology, and to evaluate potential dragging of bacteria during the cutting of slices. In all cases, the inoculum should be applied on the product using the appropriate technique, in order to mimic natural contamination. This study reports a new method of contamination that allows the achievement of homogeneous microbial distribution on the whole flat surface of foods, using absorbent paper soaked with a bacterial suspension of Listeria monocytogenes. It was tested in the framework of challenge tests aimed to quantify the dragging of bacteria from Gorgonzola cheese rinds to paste during different processing steps. The procedure could be, however, profitably used also in other food products, when uniform surface contamination is required.

Research paper thumbnail of Challenge test studies on Listeria monocytogenes in ready‐to‐eat iceberg lettuce

Food Science & Nutrition, 2019

The demand for convenient foods has increased in the last years, as consumers are interested in b... more The demand for convenient foods has increased in the last years, as consumers are interested in buying quality products ready for use. Quite often, minimally processed vegetables are usually used for meals (fresh-cut fruits, mixed salads etc.). Ready-to-eat iceberg lettuce are products that require a certain accuracy in their preparation, trying to guarantee the desired shelf life, and their safety

Research paper thumbnail of Distribution of Salmonella spp. Serotypes Isolated from Poultry in Abruzzo and Molise Regions (Italy) during a 6-Year Period

Microorganisms, 2022

Human salmonellosis incidence is increasing in the European Union (EU). Salmonella enterica subsp... more Human salmonellosis incidence is increasing in the European Union (EU). Salmonella enterica subsp. enterica serovar Enteriditis, Salmonella enterica subsp. enterica serovar Typhimurium (including its monophasic variant) and Salmonella enterica subsp. enterica serovar Infantis represent targets in control programs due to their frequent association with human cases. This study aimed to detect the most prevalent serotypes circulating in Abruzzo and Molise Regions between 2015 and 2020 in the framework of the Italian National Control Program for Salmonellosis in Poultry (PNCS)]. A total of 332 flocks of Abruzzo and Molise Regions were sampled by veterinary services in the period considered, and 2791 samples were taken. Samples were represented by faeces and dust from different categories of poultry flocks: laying hens (n = 284), broilers (n = 998), breeding chickens (n = 1353) and breeding or fattening turkeys (n = 156). Breeding and fattening turkeys had the highest rate of samples pos...

Research paper thumbnail of Recent Trends of Antibiotic Resistance in Staphylococcus aureus Causing Clinical Mastitis in Dairy Herds in Abruzzo and Molise Regions, Italy

This study was aimed to examine the recent trends of antibiotic resistance (AR) prevalence in Sta... more This study was aimed to examine the recent trends of antibiotic resistance (AR) prevalence in Staphylococcus aureus isolated from milk of animals with clinical mastitis in areas of the Abruzzo and Molise regions in central Italy. Fifty-four S. aureus isolates could be obtained from routine testing for clinical mastitis agents carried out in the author institution in years 2021 and 2022. These were analyzed for phenotypic resistance to eight antibiotics recommended for testing by European norms and belonging to the antibiotic classes used for mastitis treatment in milk producing animals. Moreover, the presence of 14 transferable genetic determinants encoding resistance to the same antibiotics was analyzed by qPCR tests developed in this study. Phenotypic resistance to non-β-lactams was infrequent, with only one 2022 isolate resistant to clindamycin. However, low level resistance to the β-lactam cefoxitin was observed in 59.2% isolates in both years making these isolates classifiable ...

Research paper thumbnail of Survival rate of Escherichia coli O157 in artificially contaminated raw and thermized ewe milk in different Pecorino cheese production processes

International Journal of Food Microbiology

Pecorino is a typical Italian cheese, mostly produced in central and southern Italy regions using... more Pecorino is a typical Italian cheese, mostly produced in central and southern Italy regions using ewe raw milk and following traditional procedures. The use of raw milk constitutes a risk linked to the potential survival or multiplication of pathogenic microorganisms, as Shiga toxin-producing Escherichia coli (STEC). The aim of this study was to compare different Italian traditional Pecorino production methods to determine if there were any phases that could influence the Escherichia coli O157 survival rate, but also if they could negatively influence lactic acid bacteria survival rate, during the phases of production and ripening. Therefore batches of Pecorino cheese were prepared using different production methods, representing the real and typical cheese production in southern and central Italy regions: 1) heating the milk at 37 °C for about 40 min before curding, 2) heating the milk at 60 °C (thermization) for 13 min, so that the alkaline phosphatase reaction is still positive before curding, 3) cooking curd at 41 °C and 4) at 45 °C, both for 5 min. Our results demonstrated that traditional milk treatments different from pasteurization can help but do not eliminate serious microbiological treats, as E. coli O157, especially if the raw milk is heavily contaminated. The heat treatment at 60 °C applied to raw milk was able to decrease the concentration of E. coli O157 of 1.7 log10CFU/ml and, according to the inactivation slope, it would be further reduced prolonging the heating treatment. The results obtained also showed that, during the Pecorino cheese ripening, E. coli O157 was always enumerable for 60 days, remaining detectable after 90 days of ripening.

Research paper thumbnail of Variability of the microbiota in traditional Caciocavallo, Scamorza and Caciotta cheeses manufactured with raw milk and natural cultures

International Journal of Dairy Technology

Research paper thumbnail of Characterization of Lactic Acid Bacteria in Pecorino DI Farindola Cheese and Manufacturing with a Lacticaseibacillus Paracasei Autochthonous Culture

This study focused on the characterization of lactic acid bacteria (LAB) in a renowned traditiona... more This study focused on the characterization of lactic acid bacteria (LAB) in a renowned traditional Italian cheese, Pecorino di Farindola, to select an autochthonous culture and investigate its po-tential for the improvement of safety and functional properties. Two hundred and six LAB isolated throughout production and maturation from nine cheese lots of three farms were identified by 16S rRNA gene sequencing and tested for the presence of genes encoding virulence factors, vancomycin resistance (for enterococci), biogenic amines (BAs) and bacteriocin production, for antimicrobial activity, and for the capacity to survive in the gastro-intestinal tract (GIT) based on tolerance to low pH and bile salts and adhesion to CaCo-2 cells. A Lacticaseibacillus paracasei isolate was used in cheese making and determined a decline of spiked Listeria monocytogenes and Escherichia coli O157 faster than in control cheese. The autochthonous bacterial groups were numerically unaffected, apart from lac...

Research paper thumbnail of A new procedure for surface contamination of food products using absorbent paper

Journal of Food Safety, 2018

A new method was developed for artificial contamination of food products during challenge test st... more A new method was developed for artificial contamination of food products during challenge test studies, in products where superficial contamination is needed. Rinds of Gorgonzola cheese wheels were divided into quarters and then squares with 12 cm of side and contaminated with absorbent paper soaked with a bacterial suspension of Listeria monocytogenes left in contact with the surface of the blue-veined cheese, in order to achieve homogenous contamination of the whole surface. To verify the performance of the method of contamination, after 24 hr L. monocytogenes was enumerated to evaluate surface contamination. With the method described, an average concentration of about 5 log 10 cfu/cm 2 or MPN/cm 2 was obtained starting from a contaminated suspension of 8 log 10 cfu/ml. The homogeneity of the contamination was demonstrated by the application of statistical tests. Practical applications Challenge tests are carried out to simulate contaminations as they happen during the processing and aging of cheeses, cured meats or ready-to-eat foods, for cross contamination studies, for applications of predictive microbiology, and to evaluate potential dragging of bacteria during the cutting of slices. In all cases, the inoculum should be applied on the product using the appropriate technique, in order to mimic natural contamination. This study reports a new method of contamination that allows the achievement of homogeneous microbial distribution on the whole flat surface of foods, using absorbent paper soaked with a bacterial suspension of Listeria monocytogenes. It was tested in the framework of challenge tests aimed to quantify the dragging of bacteria from Gorgonzola cheese rinds to paste during different processing steps. The procedure could be, however, profitably used also in other food products, when uniform surface contamination is required.

Research paper thumbnail of Challenge test studies on Listeria monocytogenes in ready‐to‐eat iceberg lettuce

Food Science & Nutrition, 2019

The demand for convenient foods has increased in the last years, as consumers are interested in b... more The demand for convenient foods has increased in the last years, as consumers are interested in buying quality products ready for use. Quite often, minimally processed vegetables are usually used for meals (fresh-cut fruits, mixed salads etc.). Ready-to-eat iceberg lettuce are products that require a certain accuracy in their preparation, trying to guarantee the desired shelf life, and their safety

Research paper thumbnail of Distribution of Salmonella spp. Serotypes Isolated from Poultry in Abruzzo and Molise Regions (Italy) during a 6-Year Period

Microorganisms, 2022

Human salmonellosis incidence is increasing in the European Union (EU). Salmonella enterica subsp... more Human salmonellosis incidence is increasing in the European Union (EU). Salmonella enterica subsp. enterica serovar Enteriditis, Salmonella enterica subsp. enterica serovar Typhimurium (including its monophasic variant) and Salmonella enterica subsp. enterica serovar Infantis represent targets in control programs due to their frequent association with human cases. This study aimed to detect the most prevalent serotypes circulating in Abruzzo and Molise Regions between 2015 and 2020 in the framework of the Italian National Control Program for Salmonellosis in Poultry (PNCS)]. A total of 332 flocks of Abruzzo and Molise Regions were sampled by veterinary services in the period considered, and 2791 samples were taken. Samples were represented by faeces and dust from different categories of poultry flocks: laying hens (n = 284), broilers (n = 998), breeding chickens (n = 1353) and breeding or fattening turkeys (n = 156). Breeding and fattening turkeys had the highest rate of samples pos...