Sara Primavilla, Silvana Farneti, Rossana Roila, Raffaella Branciari, Caterina Altissimi, Andrea Valiani, David Ranucci
Yersinia enterocolitica represents one of the main foodborne pathogens in Europe and the evaluation of possible sources of contamination and its prevalence in food is of considerable interest for risk analysis approach. The results of the search for Yersinia enterocolitica in food samples taken in Umbria region (central Italy) were evaluated during the years 2015-2018. Different types of foods were considered, both ready-to-eat (meat products, dairy products, and raw vegetables) and meat preparations to be eaten after cooking. Samples were assayed by molecular screening for the species indicator gene ompF. Screening positives were subjected to isolation and characterization by searching for specific virulence marker genes, including the ail gene responsible for invasiveness and the ystB gene for the production of enterotoxin. The total prevalence of positive samples for Yersinia enterocolitica was 16.86% with a higher percentage of positive samples in meat preparations (19.35%), followed by ready-to-eat vegetables (11.76%). Poultry meat samples had a higher prevalence than pork and beef samples. Neither positive samples were found in meat products and dairy, nor seasonality in positivity was observed. All isolated strains of Yersinia enterocolitica were biotype 1A, with absence of the ail virulence gene but presence of ystB gene. Since the strains isolated from human patients appear to be primarily biotypes that possess the ail marker, future investigations would be needed regarding the real role of biotype 1A in human disease. In this context, attention should certainly be paid to ready-to-eat vegetables and to careful cooking of meat preparations.
{"title":"Retrospective study on the prevalence of <i>Yersinia enterocolitica</i> in food collected in Umbria region (central Italy).","authors":"Sara Primavilla, Silvana Farneti, Rossana Roila, Raffaella Branciari, Caterina Altissimi, Andrea Valiani, David Ranucci","doi":"10.4081/ijfs.2023.10996","DOIUrl":"https://doi.org/10.4081/ijfs.2023.10996","url":null,"abstract":"<p><p><i>Yersinia enterocolitica</i> represents one of the main foodborne pathogens in Europe and the evaluation of possible sources of contamination and its prevalence in food is of considerable interest for risk analysis approach. The results of the search for <i>Yersinia enterocolitica</i> in food samples taken in Umbria region (central Italy) were evaluated during the years 2015-2018. Different types of foods were considered, both ready-to-eat (meat products, dairy products, and raw vegetables) and meat preparations to be eaten after cooking. Samples were assayed by molecular screening for the species indicator gene <i>ompF</i>. Screening positives were subjected to isolation and characterization by searching for specific virulence marker genes, including the <i>ail</i> gene responsible for invasiveness and the <i>ystB</i> gene for the production of enterotoxin. The total prevalence of positive samples for <i>Yersinia enterocolitica</i> was 16.86% with a higher percentage of positive samples in meat preparations (19.35%), followed by ready-to-eat vegetables (11.76%). Poultry meat samples had a higher prevalence than pork and beef samples. Neither positive samples were found in meat products and dairy, nor seasonality in positivity was observed. All isolated strains of <i>Yersinia enterocolitica</i> were biotype 1A, with absence of the <i>ail</i> virulence gene but presence of <i>ystB</i> gene. Since the strains isolated from human patients appear to be primarily biotypes that possess the <i>ail</i> marker, future investigations would be needed regarding the real role of biotype 1A in human disease. In this context, attention should certainly be paid to ready-to-eat vegetables and to careful cooking of meat preparations.</p>","PeriodicalId":14508,"journal":{"name":"Italian Journal of Food Safety","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2023-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/a1/d4/ijfs-12-1-10996.PMC10102966.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9317409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Persistent bacteria are a microbial subpopulation that, exposed to bactericidal treatment, is killed at a slower rate than the rest of the population they are part of. They can be triggered either following stress or stochastically without external signals. The hallmark of persistent bacteria is the biphasic killing curve, a sign that, within a microbial population, two subpopulations are inactivated at a different rate. Furthermore, when plated into a fresh medium and in the absence of stressors, persistent bacteria typically remain in the lag phase longer before resuming active replication. This study aims to evaluate in vitro whether the formation of persistent cells in a strain of Listeria monocytogenes can be triggered by exposure to osmotic stress and if this phenomenon can increase heat resistance in the bacterial population. In a first experiment, the lag time distribution of a L. monocytogenes strain grown in a 6% NaCl broth was evaluated using the software ScanLag. A stationary phase broth culture was inoculated on agar plates placed on an office scanner inside an incubator at 37°C. The plates were scanned every 20' for 4 days and the acquired images were automatically elaborated with the aid of MatLab software in order to evaluate the appearance times of every single colony. The experiment was also carried out on a control culture obtained by growing the strain in the broth without salt. In a second experiment, the same broth cultures, after proper dilutions to rebalance NaCl concentration, were subjected to a heat treatment at 51°C and the death curves obtained were parameterized using the GinaFit system. Results showed that the lag phase of 31.40% of the salt culture colonies was long enough to suppose the formation of persistent bacteria. Analyses of the thermal survival curves showed that the shoulder and tail model was the one that best represented the inactivation trend of the salt culture, unlike the control culture, whose trend was essentially linear. Results of the present study show how exposure to salt could induce the formation of persistent bacteria in a L. monocytogenes strain. The last raises concerns as persistent cells may not only be undetected with common analytical techniques but they even show a greater heat resistance.
{"title":"Effects of osmotic stress on <i>Listeria monocytogenes</i> ATCC 7644: persistent cells and heat resistance.","authors":"Luca Nalbone, Giorgia Sorrentino, Filippo Giarratana, Aurelian Schiopu-Mariean, Graziella Ziino, Alessandro Giuffrida","doi":"10.4081/ijfs.2023.10880","DOIUrl":"https://doi.org/10.4081/ijfs.2023.10880","url":null,"abstract":"<p><p>Persistent bacteria are a microbial subpopulation that, exposed to bactericidal treatment, is killed at a slower rate than the rest of the population they are part of. They can be triggered either following stress or stochastically without external signals. The hallmark of persistent bacteria is the biphasic killing curve, a sign that, within a microbial population, two subpopulations are inactivated at a different rate. Furthermore, when plated into a fresh medium and in the absence of stressors, persistent bacteria typically remain in the lag phase longer before resuming active replication. This study aims to evaluate <i>in vitro</i> whether the formation of persistent cells in a strain of <i>Listeria monocytogenes</i> can be triggered by exposure to osmotic stress and if this phenomenon can increase heat resistance in the bacterial population. In a first experiment, the lag time distribution of a <i>L. monocytogenes</i> strain grown in a 6% NaCl broth was evaluated using the software ScanLag. A stationary phase broth culture was inoculated on agar plates placed on an office scanner inside an incubator at 37°C. The plates were scanned every 20' for 4 days and the acquired images were automatically elaborated with the aid of MatLab software in order to evaluate the appearance times of every single colony. The experiment was also carried out on a control culture obtained by growing the strain in the broth without salt. In a second experiment, the same broth cultures, after proper dilutions to rebalance NaCl concentration, were subjected to a heat treatment at 51°C and the death curves obtained were parameterized using the GinaFit system. Results showed that the lag phase of 31.40% of the salt culture colonies was long enough to suppose the formation of persistent bacteria. Analyses of the thermal survival curves showed that the <i>shoulder</i> and <i>tail</i> model was the one that best represented the inactivation trend of the salt culture, unlike the control culture, whose trend was essentially linear. Results of the present study show how exposure to salt could induce the formation of persistent bacteria in a <i>L. monocytogenes</i> strain. The last raises concerns as persistent cells may not only be undetected with common analytical techniques but they even show a greater heat resistance.</p>","PeriodicalId":14508,"journal":{"name":"Italian Journal of Food Safety","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2023-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/4f/6a/ijfs-12-1-10880.PMC10102965.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9372109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Francesca Marconi, Martina Sartoni, Roberta Nuvoloni, Beatrice Torracca, Matteo Gagliardi, Giulia Zappalà, Alessandra Guidi, Francesca Pedonese
The Commission Regulation (EU) No. 2021/382 (European Commission, 2021), amending the Regulation (EC) No. 852/2004 (European Commission, 2004), introduced the obligation for companies to establish and maintain a food safety culture (FSC). The methodology to evaluate, implement, and enhance the level of FSC is up to the individual companies. This study aimed to investigate the perception of FSC among the employees of 3 Tuscan medium-sized enterprises in the food sector, producing cured meat (A), dairy products (B), and frozen fish products (C). The survey was conducted through the development and administration of a questionnaire based on a 5 points Likert scale, referring to different aspects of FSC, organized in 6 sections with 5-6 statements each and subjected to a percentage of employees between 76 and 85%, classified also by the length of service (≤3 and >3 years). For all the companies, the minimum median and mode value for scores obtained by the different sections was 4, and the minimum median and mode value for the single statement was 3 (A, B; except for a bimodal value 2-4) and 4 (C). The section awareness and perception of risk showed the highest mean scores in all companies. As for the length of service, senior employees gave lower scores than junior ones in all sections in B and 3 sections in C. Overall, the results of the questionnaires showed a good perception of FSC, even though it was possible to identify some partial weaknesses.
委员会法规(EU) No 2021/382 (European Commission, 2021)修订了法规(EC) No 852/2004 (European Commission, 2004),引入了公司建立和维护食品安全文化(FSC)的义务。评价、实施和提高金融监督管理水平的方法取决于各个公司。本研究旨在调查三家托斯卡纳中型食品企业的员工对FSC的看法,这些企业生产腌制肉类(A)、乳制品(B)和冷冻鱼类产品(C)。该调查是通过开发和管理一份基于5分李克特量表的问卷来进行的,涉及FSC的不同方面,分为6个部分,每个部分有5-6个陈述,员工的比例在76 - 85%之间。按服务年限划分(≤3年和>3年)。对于所有公司,不同部门获得的分数的最小中位数和模式值为4,单个语句的最小中位数和模式值为3 (A, B;除了双峰值2-4)和4 (C)外,所有公司的风险意识和感知部分的平均得分最高。在服务年限方面,B的所有部分和c的3个部分中,高级员工的得分都低于初级员工。总体而言,调查结果显示,尽管可以发现一些部分的弱点,但对FSC的认知还是很好的。
{"title":"Food safety culture in food companies: evaluation of the perception of food safety culture in three Tuscan food companies.","authors":"Francesca Marconi, Martina Sartoni, Roberta Nuvoloni, Beatrice Torracca, Matteo Gagliardi, Giulia Zappalà, Alessandra Guidi, Francesca Pedonese","doi":"10.4081/ijfs.2023.11012","DOIUrl":"https://doi.org/10.4081/ijfs.2023.11012","url":null,"abstract":"<p><p>The Commission Regulation (EU) No. 2021/382 (European Commission, 2021), amending the Regulation (EC) No. 852/2004 (European Commission, 2004), introduced the obligation for companies to establish and maintain a food safety culture (FSC). The methodology to evaluate, implement, and enhance the level of FSC is up to the individual companies. This study aimed to investigate the perception of FSC among the employees of 3 Tuscan medium-sized enterprises in the food sector, producing cured meat (A), dairy products (B), and frozen fish products (C). The survey was conducted through the development and administration of a questionnaire based on a 5 points Likert scale, referring to different aspects of FSC, organized in 6 sections with 5-6 statements each and subjected to a percentage of employees between 76 and 85%, classified also by the length of service (≤3 and >3 years). For all the companies, the minimum median and mode value for scores obtained by the different sections was 4, and the minimum median and mode value for the single statement was 3 (A, B; except for a bimodal value 2-4) and 4 (C). The section <i>awareness and perception of risk</i> showed the highest mean scores in all companies. As for the length of service, senior employees gave lower scores than junior ones in all sections in B and 3 sections in C. Overall, the results of the questionnaires showed a good perception of FSC, even though it was possible to identify some partial weaknesses.</p>","PeriodicalId":14508,"journal":{"name":"Italian Journal of Food Safety","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2023-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/df/bf/ijfs-12-1-11012.PMC10102961.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9317411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lucia Gambi, Cecilia Crippa, Alex Lucchi, Gerardo Manfreda, Alessandra de Cesare, Frédérique Pasquali
In the present study, the occurrence of Listeria monocytogenes, Staphylococcus aureus, Salmonella spp. and Escherichia coli VTEC was investigated in two batches of artisanal Italian salami tested in winter and summer. Moreover, enumerations of total bacterial count, lactic acid bacteria and Enterobacteriaceae were performed as well as monitoring of water activity and pH. Samples were taken from raw materials, production process environment, semi-finished product and finished products. The results revealed an overall increase of total bacterial count and lactic acid bacteria during the ripening period, along with a decrease of Enterobacteriaceae, pH and water activity. No significant difference was observed between the two batches. The enterobacterial load appeared to decrease during the maturation period mainly due to a decrease in pH and water activity below the limits that allow the growth of these bacteria. E. coli VTEC, Salmonella spp. or L. monocytogenes were not detected in both winter and summer batches. However, Klebsiella pneumoniae was detected in both summer and winter products. Except for one isolate, no biological hazards were detected in the finished salami, proving the efficacy of the ripening period in controlling the occurrence of microbiological hazard in ripened salami. Further studies are required to assess the virulence potential of the Klebsiella pneumoniae isolates.
{"title":"Investigation on the microbiological hazards in an artisanal salami produced in Northern Italy and its production environment in different seasonal periods.","authors":"Lucia Gambi, Cecilia Crippa, Alex Lucchi, Gerardo Manfreda, Alessandra de Cesare, Frédérique Pasquali","doi":"10.4081/ijfs.2023.10831","DOIUrl":"https://doi.org/10.4081/ijfs.2023.10831","url":null,"abstract":"<p><p>In the present study, the occurrence of <i>Listeria monocytogenes</i>, <i>Staphylococcus aureus</i>, <i>Salmonella spp</i>. and <i>Escherichia coli</i> VTEC was investigated in two batches of artisanal Italian salami tested in winter and summer. Moreover, enumerations of total bacterial count, lactic acid bacteria and <i>Enterobacteriaceae</i> were performed as well as monitoring of water activity and pH. Samples were taken from raw materials, production process environment, semi-finished product and finished products. The results revealed an overall increase of total bacterial count and lactic acid bacteria during the ripening period, along with a decrease of <i>Enterobacteriaceae</i>, pH and water activity. No significant difference was observed between the two batches. The enterobacterial load appeared to decrease during the maturation period mainly due to a decrease in pH and water activity below the limits that allow the growth of these bacteria. <i>E. coli</i> VTEC, <i>Salmonella</i> spp. or <i>L. monocytogenes</i> were not detected in both winter and summer batches. However, <i>Klebsiella pneumoniae</i> was detected in both summer and winter products. Except for one isolate, no biological hazards were detected in the finished salami, proving the efficacy of the ripening period in controlling the occurrence of microbiological hazard in ripened salami. Further studies are required to assess the virulence potential of the <i>Klebsiella pneumoniae</i> isolates.</p>","PeriodicalId":14508,"journal":{"name":"Italian Journal of Food Safety","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2023-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/f0/39/ijfs-12-1-10831.PMC10102968.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9317413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Biofilms represent an evolutionary form of life, which translates from life in free-living cells to a community lifestyle. In natural habitats, biofilms are a multispecies complex, where synergies or antagonisms can be established. For example, Listeria monocytogenes and Pseudomonas fluorescens are associated with a dual-species biofilm that is widespread in dairy plants. In food plants, multiple strategies are devised to control biofilms, including natural compounds such as essential oils (EOs). In this respect, this study evaluated the effectiveness of Thymbra capitata (L.) Cav. (TEO) and Cinnamomum zeylanicum (CEO) against a dual-species biofilm of L. monocytogenes and P. fluorescens, mimicking dairy process conditions. Based on Minimum Inhibitory Concentrations results, the EOs concentration (10 μL/mL) was chosen for the antibiofilm assay at 12°C on polystyrene (PS), and stainless-steel surfaces for 168 h, using a Ricotta-based model system as culture medium. Biofilm biomass was assessed by crystal violet staining, and the planktonic and sessile cells were quantified in terms of Log CFU/cm2. Results showed that CEO displayed the greatest antibiofilm activity, reducing significantly (P<0.05) P. fluorescens and L. monocytogenes sessile cells of about 2.5 and 2.8 Log CFU/cm2 after 72 h, respectively. However, L. monocytogenes gained the protection of P. fluorescens, evading CEO treatment and showing a minimal sessile cell reduction of 0.7 Log CFU/cm2 after 72 h. Considering the outcome of this study, CEO might have promising perspectives for applications in dairy facilities.
{"title":"Effectiveness of essential oils against dual-species biofilm of <i>Listeria monocytogenes and Pseudomonas fluorescens</i> in a Ricotta-based model system.","authors":"Francesca Maggio, Annalisa Serio, Chiara Rossi, Chiara Purgatorio, Francesco Buccioni, Clemencia Chaves-López, Antonello Paparella","doi":"10.4081/ijfs.2023.11048","DOIUrl":"https://doi.org/10.4081/ijfs.2023.11048","url":null,"abstract":"<p><p>Biofilms represent an evolutionary form of life, which translates from life in free-living cells to a community lifestyle. In natural habitats, biofilms are a multispecies complex, where synergies or antagonisms can be established. For example, <i>Listeria monocytogenes</i> and <i>Pseudomonas fluorescens</i> are associated with a dual-species biofilm that is widespread in dairy plants. In food plants, multiple strategies are devised to control biofilms, including natural compounds such as essential oils (EOs). In this respect, this study evaluated the effectiveness of <i>Thymbra capitata</i> (L.) Cav. (TEO) and <i>Cinnamomum zeylanicum</i> (CEO) against a dual-species biofilm of <i>L. monocytogenes</i> and <i>P. fluorescens</i>, mimicking dairy process conditions. Based on Minimum Inhibitory Concentrations results, the EOs concentration (10 μL/mL) was chosen for the antibiofilm assay at 12°C on polystyrene (PS), and stainless-steel surfaces for 168 h, using a Ricotta-based model system as culture medium. Biofilm biomass was assessed by crystal violet staining, and the planktonic and sessile cells were quantified in terms of Log CFU/cm<sup>2</sup>. Results showed that CEO displayed the greatest antibiofilm activity, reducing significantly (P<0.05) <i>P. fluorescens</i> and <i>L. monocytogenes</i> sessile cells of about 2.5 and 2.8 Log CFU/cm<sup>2</sup> after 72 h, respectively. However, <i>L. monocytogenes</i> gained the protection of <i>P. fluorescens</i>, evading CEO treatment and showing a minimal sessile cell reduction of 0.7 Log CFU/cm<sup>2</sup> after 72 h. Considering the outcome of this study, CEO might have promising perspectives for applications in dairy facilities.</p>","PeriodicalId":14508,"journal":{"name":"Italian Journal of Food Safety","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2023-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/db/c7/ijfs-12-1-11048.PMC10102963.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9317414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rita Sanna, Francesca Piras, Giuliana Siddi, Maria Pina Meloni, Mariella Demontis, Vincenzo Spanu, Gavino Nieddu, Mario Cuccu, Enrico Pietro Luigi De Santis, Christian Scarano
The main objective of this study was to innovate soft and semi-cooked sheep milk cheese production processes with the use of a commercial protective culture able to control Listeria monocytogenes growth. A freeze-dried commercial culture of Lactobacillus plantarum was tested in DS cheese and PS cheese, two types of pasteurized sheep milk, raw-paste cheeses aged for no less than 20 and 30 days respectively. In the first step, in vitro tests were conducted to identify the most suitable matrix for the growth of L. plantarum in order to create a subculture that could be used at industrial cheese-making plants. During the second phase of the study, L. plantarum culture was introduced in the manufacturing process of the cheeses in a production plant. Finally, a challenge test was conducted on portioned DS and PS cheeses in order to evaluate the activity of the protective culture against L. monocytogenes: the cheeses were portioned, experimentally contaminated with L. monocytogenes strains, vacuum packed and stored at +4°C (correct storage conditions) and at +10°C (thermal abuse). Cheeses were analysed at the end of the shelf-life to evaluate the presence and growth of L. monocytogenes, to enumerate lactic acid bacteria and determine chemicalphysical features. The results confirmed that protective cultures are a useful technological innovation to control L. monocytogenes growth during cheese storage without altering composition, microflora and chemical- physical characteristics of the product. However, the use of protective cultures should be applied as an integration of risk control measures and not as a substitute for preventive actions.
{"title":"Use of commercial protective cultures in portioned sheep milk cheeses to control <i>Listeria monocytogenes</i>.","authors":"Rita Sanna, Francesca Piras, Giuliana Siddi, Maria Pina Meloni, Mariella Demontis, Vincenzo Spanu, Gavino Nieddu, Mario Cuccu, Enrico Pietro Luigi De Santis, Christian Scarano","doi":"10.4081/ijfs.2023.10484","DOIUrl":"https://doi.org/10.4081/ijfs.2023.10484","url":null,"abstract":"<p><p>The main objective of this study was to innovate soft and semi-cooked sheep milk cheese production processes with the use of a commercial protective culture able to control <i>Listeria monocytogenes</i> growth. A freeze-dried commercial culture of <i>Lactobacillus plantarum</i> was tested in DS cheese and PS cheese, two types of pasteurized sheep milk, raw-paste cheeses aged for no less than 20 and 30 days respectively. In the first step, <i>in vitro</i> tests were conducted to identify the most suitable matrix for the growth of <i>L. plantarum</i> in order to create a subculture that could be used at industrial cheese-making plants. During the second phase of the study, <i>L. plantarum</i> culture was introduced in the manufacturing process of the cheeses in a production plant. Finally, a challenge test was conducted on portioned DS and PS cheeses in order to evaluate the activity of the protective culture against <i>L. monocytogenes</i>: the cheeses were portioned, experimentally contaminated with <i>L. monocytogenes</i> strains, vacuum packed and stored at +4°C (correct storage conditions) and at +10°C (thermal abuse). Cheeses were analysed at the end of the shelf-life to evaluate the presence and growth of <i>L. monocytogenes</i>, to enumerate lactic acid bacteria and determine chemicalphysical features. The results confirmed that protective cultures are a useful technological innovation to control <i>L. monocytogenes</i> growth during cheese storage without altering composition, microflora and chemical- physical characteristics of the product. However, the use of protective cultures should be applied as an integration of risk control measures and not as a substitute for preventive actions.</p>","PeriodicalId":14508,"journal":{"name":"Italian Journal of Food Safety","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2023-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/1e/0f/ijfs-12-1-10484.PMC10102964.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9317410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mohammad Shamsur Rahman, Sarah Currò, Lisa Carraro, Barbara Cardazzo, Stefania Balzan, Enrico Novelli, Federico Fontana, Greta Caburlotto, Amedeo Manfrin, Luca Fasolato
The genus Vibrio includes bacteria with different morphological and metabolic characteristics responsible for different human and animal diseases. An accurate identification is essential to assess the risks in regard to aquatic organisms and consequently to public health. The Multilocus Sequence Analysis (MLSA) scheme developed on the basis of 4 housekeeping genes (gyrB, pyrH, recA and atpA) was applied to identify 92 Vibrio strains isolated from crustaceans in 2011. Concatenated sequences were used for the phylogenetic and population analyses and the results were compared with those from biochemical identification tests. From the phylogenetic analysis, 10 clusters and 4 singletons emerged, whereas the population analysis highlighted 12 subpopulations that were well supported by phylogeny with few exceptions. The retrospective analysis allowed correct re-attribution of isolated species, indicating how, for some pathogens, there may be an overestimation of phenotypic identification (e.g. V. parahaemolyticus). Use of the PubMLST Vibrio database highlighted a possible genetic link between Sequence Type (ST) 529 and ST195 (V. alginolyticus) isolated from a human case in Norway during 2018. In addition to the identification of major risk groups of V. cholerae, V. vulnificus and V. parahaemolyticus, MLSA could be a valid support for species considered a minor risk, such as V. alginolyticus, V. mimicus and V. fluvialis. Due to the increased incidence of vibriosis in Europe, the application of different tools will also have to be considered to investigate the possible epidemiological links of the various species in the perspective of Open Science to protect the consumer.
{"title":"Retrospective analysis of Vibrio spp. isolated from marketed crustaceans using multilocus sequence analysis.","authors":"Mohammad Shamsur Rahman, Sarah Currò, Lisa Carraro, Barbara Cardazzo, Stefania Balzan, Enrico Novelli, Federico Fontana, Greta Caburlotto, Amedeo Manfrin, Luca Fasolato","doi":"10.4081/ijfs.2023.11045","DOIUrl":"https://doi.org/10.4081/ijfs.2023.11045","url":null,"abstract":"<p><p>The genus <i>Vibrio</i> includes bacteria with different morphological and metabolic characteristics responsible for different human and animal diseases. An accurate identification is essential to assess the risks in regard to aquatic organisms and consequently to public health. The Multilocus Sequence Analysis (MLSA) scheme developed on the basis of 4 housekeeping genes (<i>gyr</i>B, <i>pyr</i>H, <i>rec</i>A and <i>atp</i>A) was applied to identify 92 <i>Vibrio</i> strains isolated from crustaceans in 2011. Concatenated sequences were used for the phylogenetic and population analyses and the results were compared with those from biochemical identification tests. From the phylogenetic analysis, 10 clusters and 4 singletons emerged, whereas the population analysis highlighted 12 subpopulations that were well supported by phylogeny with few exceptions. The retrospective analysis allowed correct re-attribution of isolated species, indicating how, for some pathogens, there may be an overestimation of phenotypic identification (<i>e.g</i>. <i>V. parahaemolyticus</i>). Use of the PubMLST <i>Vibrio</i> database highlighted a possible genetic link between Sequence Type (ST) 529 and ST195 (<i>V. alginolyticus</i>) isolated from a human case in Norway during 2018. In addition to the identification of major risk groups of <i>V. cholerae</i>, <i>V. vulnificus</i> and <i>V. parahaemolyticus</i>, MLSA could be a valid support for species considered a minor risk, such as <i>V. alginolyticus</i>, <i>V. mimicus</i> and <i>V. fluvialis</i>. Due to the increased incidence of vibriosis in Europe, the application of different tools will also have to be considered to investigate the possible epidemiological links of the various species in the perspective of <i>Open Science</i> to protect the consumer.</p>","PeriodicalId":14508,"journal":{"name":"Italian Journal of Food Safety","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2023-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/81/21/ijfs-12-1-11045.PMC10102960.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9321854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Foodborne illnesses are responsible for about half a million deaths annually, of which 30% occur among kids. This study aimed to assess the current food safety knowledge and practice level of Saudi women in Al-Ahsa region, Saudi Arabia. A cross-sectional study was conducted through personal interviews among 239 Saudi women. The questionnaire consisted of close-ended questions covering different aspects of food safety knowledge and practices at home and during shopping. Descriptive analyses were used to identify the level of participant's awareness, and the scores were shown in three categories (good - fair - poor) based on their food safety knowledge and practice awareness. The effect of socio-demographic characteristics and their correlation to food safety knowledge and practices was conducted using Chisquare analysis. The results about food safety knowledge showed that around 50% of participants achieved a good score, and 37.5% achieved a fair score, while 12.5% achieved a poor score. In comparison, the participants achieved 75% good score, whereas 12.5% achieved both fair and poor in food safety practices. The results also highlighted a significant correlation (P<0.05) between level of food safety knowledge, practices of participants and their age, marital status, work status, and educational level, while there's no correlation with their family size and total income. Although, the overall result showed good level in food safety knowledge and slightly less in food safety practices among Saudi women living in Al-Ahsa region, continuous education, training, awareness, and motivation are highly recommended to improve women's knowledge and practices to higher levels.
{"title":"Evaluating food safety knowledge and practices among Saudi women in Al-Ahsa Region, Saudi Arabia.","authors":"Fahad Al-Asmari, Ahmed I H Ismail","doi":"10.4081/ijfs.2023.10716","DOIUrl":"https://doi.org/10.4081/ijfs.2023.10716","url":null,"abstract":"<p><p>Foodborne illnesses are responsible for about half a million deaths annually, of which 30% occur among kids. This study aimed to assess the current food safety knowledge and practice level of Saudi women in Al-Ahsa region, Saudi Arabia. A cross-sectional study was conducted through personal interviews among 239 Saudi women. The questionnaire consisted of close-ended questions covering different aspects of food safety knowledge and practices at home and during shopping. Descriptive analyses were used to identify the level of participant's awareness, and the scores were shown in three categories (good - fair - poor) based on their food safety knowledge and practice awareness. The effect of socio-demographic characteristics and their correlation to food safety knowledge and practices was conducted using Chisquare analysis. The results about food safety knowledge showed that around 50% of participants achieved a good score, and 37.5% achieved a fair score, while 12.5% achieved a poor score. In comparison, the participants achieved 75% good score, whereas 12.5% achieved both fair and poor in food safety practices. The results also highlighted a significant correlation (P<0.05) between level of food safety knowledge, practices of participants and their age, marital status, work status, and educational level, while there's no correlation with their family size and total income. Although, the overall result showed good level in food safety knowledge and slightly less in food safety practices among Saudi women living in Al-Ahsa region, continuous education, training, awareness, and motivation are highly recommended to improve women's knowledge and practices to higher levels.</p>","PeriodicalId":14508,"journal":{"name":"Italian Journal of Food Safety","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2023-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/ee/50/ijfs-12-1-10716.PMC10102962.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9317412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Duri Lee, Thinh Dinh Do, Jong-Won Baek, Min-Ho Mun, Hyung-Eun An, Chang-Bae Kim
Due to the close relationship between pets and humans, pet owners are highly invested in proper diets for their pets. Even though pet food mislabeling is concerning, there are few studies on this topic. This study investigated pet food mislabeling in South Korea's market based on DNA barcoding. In total, 10 pet food products were purchased, and 200 sequences of the partial Cytochrome c oxidase subunit 1 (COI) gene were generated from clones of the samples. The obtained sequences were compared to available public databases to identify species present in the ingredients. The data analyses showed that the labeled species were consistent with species detected by COI sequences in 6 of the products. However, the expected species were not detected in 4 products, revealing possible mislabeling in these samples. Our findings indicated that DNA barcoding might represent a promising tool to detect pet food mislabeling.
{"title":"A case study on DNA barcoding for pet food mislabeling in South Korea.","authors":"Duri Lee, Thinh Dinh Do, Jong-Won Baek, Min-Ho Mun, Hyung-Eun An, Chang-Bae Kim","doi":"10.4081/ijfs.2023.11074","DOIUrl":"https://doi.org/10.4081/ijfs.2023.11074","url":null,"abstract":"<p><p>Due to the close relationship between pets and humans, pet owners are highly invested in proper diets for their pets. Even though pet food mislabeling is concerning, there are few studies on this topic. This study investigated pet food mislabeling in South Korea's market based on DNA barcoding. In total, 10 pet food products were purchased, and 200 sequences of the partial Cytochrome c oxidase subunit 1 (COI) gene were generated from clones of the samples. The obtained sequences were compared to available public databases to identify species present in the ingredients. The data analyses showed that the labeled species were consistent with species detected by COI sequences in 6 of the products. However, the expected species were not detected in 4 products, revealing possible mislabeling in these samples. Our findings indicated that DNA barcoding might represent a promising tool to detect pet food mislabeling.</p>","PeriodicalId":14508,"journal":{"name":"Italian Journal of Food Safety","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2023-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/f4/04/ijfs-12-1-11074.PMC10102958.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9321853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The ingestion of synthetic microfibers, the most prevalent type of microplastics in marine environments, and natural fibers was assessed in Engraulis engrasicolus and Mullus barbatus, two commercially important fish species in the Mediterranean Sea. Microfibers were isolated from the fish gastrointestinal tract using a 10% potassium hydroxide solution. For the microfiber characterization, the evaluation of specific morphological features using a light microscope, coupled with the Fourier-transform infrared (FTIR) analysis of a subsample of isolated particles, was applied. The preliminary results showed the occurrence of microfibers in 53 and 60% of European anchovy and Red mullet, respectively. A mean of 6.9 microfibers/individual was detected in anchovies, while on average Red mullet samples contained 9.2 microfibers/individual. The most common colors of fibers in both species were black, blue, and transparent. Visual characterization of fibers allowed the classification of 40% of the items as synthetic microfibers. FTIR spectroscopy confirmed the visual classification by fiber morphology. Microfibers were made of different typologies of polymers, represented by cellulose, cotton, and polyester. These findings confirm as the wide distribution of fibrous microplastics, and natural microfibers may impact both pelagic and deep-sea trophic webs. Despite the presence of microfibers in fish species poses a potential risk to human health, the literature is scarce regarding studies on the uptake by commercial marine fish mostly due to methodological issues. The visual characterization, corroborated by spectroscopic techniques, may be useful to differentiate synthetic and natural fibers, representing a fast and easy method to assess fibrous microplastic pollution in commercially important fish species.
{"title":"Research and characterization of fibrous microplastics and natural microfibers in pelagic and benthic fish species of commercial interest.","authors":"Serena Santonicola, Michela Volgare, Emilia Di Pace, Raffaelina Mercogliano, Mariacristina Cocca, Gennaro Raimo, Giampaolo Colavita","doi":"10.4081/ijfs.2023.11032","DOIUrl":"https://doi.org/10.4081/ijfs.2023.11032","url":null,"abstract":"<p><p>The ingestion of synthetic microfibers, the most prevalent type of microplastics in marine environments, and natural fibers was assessed in <i>Engraulis engrasicolus</i> and <i>Mullus barbatus</i>, two commercially important fish species in the Mediterranean Sea. Microfibers were isolated from the fish gastrointestinal tract using a 10% potassium hydroxide solution. For the microfiber characterization, the evaluation of specific morphological features using a light microscope, coupled with the Fourier-transform infrared (FTIR) analysis of a subsample of isolated particles, was applied. The preliminary results showed the occurrence of microfibers in 53 and 60% of European anchovy and Red mullet, respectively. A mean of 6.9 microfibers/individual was detected in anchovies, while on average Red mullet samples contained 9.2 microfibers/individual. The most common colors of fibers in both species were black, blue, and transparent. Visual characterization of fibers allowed the classification of 40% of the items as synthetic microfibers. FTIR spectroscopy confirmed the visual classification by fiber morphology. Microfibers were made of different typologies of polymers, represented by cellulose, cotton, and polyester. These findings confirm as the wide distribution of fibrous microplastics, and natural microfibers may impact both pelagic and deep-sea trophic webs. Despite the presence of microfibers in fish species poses a potential risk to human health, the literature is scarce regarding studies on the uptake by commercial marine fish mostly due to methodological issues. The visual characterization, corroborated by spectroscopic techniques, may be useful to differentiate synthetic and natural fibers, representing a fast and easy method to assess fibrous microplastic pollution in commercially important fish species.</p>","PeriodicalId":14508,"journal":{"name":"Italian Journal of Food Safety","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2023-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/44/1c/ijfs-12-1-11032.PMC10102967.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9317415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}