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Aaron C. Williams - One of the best experts on this subject based on the ideXlab platform.
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Thermal destruction of Listeria monocytogenes during Liver Sausage processing
Food Microbiology, 1993Co-Authors: Samuel A. Palumbo, C. Turner-jones, Benne S. Marmer, Saumya Bhaduri, Laura L Zaika, James L. Smith, Aaron C. WilliamsAbstract:Abstract We studied the inactivation of Listeria monocytogenes during the thermal processing of Liver Sausage. Liver Sausage emulsion was prepared and inoculated with L. monocytogenes Scott A to yield an initial population of c. 10 9 g -1 . The inoculated emulsion was stuffed into large diameter, moisture-proof fibrous casings and cooked in a smokehouse. Individual Sausages were removed as the product reached various predetermined internal temperatures, and duplicate core samples were analyzed for viable L. monocytogenes by surface plating onto tryptose agar. The viable count remained unchanged in product heated to 140°F. In product heated to 145°F, the number of viable L. monocytogenes decreased and at 155°F, no viable L. monocytogenes were detected. Thus, Liver Sausage and other large diameter non-fermented Sausage product heated to 155°F should be free of viable L. monocytogenes.
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thermal destruction oflisteria monocytogenes in Liver Sausage slurry
Food Microbiology, 1991Co-Authors: Saumya Bhaduri, Benne S. Marmer, Laura L Zaika, James L. Smith, Samuel A. Palumbo, Phillip W Smith, C Turnerjones, Robert L Buchanan, Aaron C. WilliamsAbstract:Abstract Thermal destruction ofListeria monocytogenes was determined in a Liver Sausage slurry (1:1, Liver Sausage batter and water) using a submerged ampule technique.D-values forL. monocytogenes Scott A grown at 37°C were 8·9 min at 57·2°C, 2·4 min at 60·0°C, and 1·1 min at 62·8°C (Z=6·2°C) based on analysis of the linear portion of the survivor curves.D-values of 6·6, 1·6, and 0·4 min (Z=4·65°C) were obtained when the data were analyzed using non-linear techniques.L. monocytogenes strain V7 (D60=1.0min) was more thermosensitive than Scott A (D60=1·6min) or HO-VJ-S (D60=1·6min). When Scott A was grown at 19°C, there was a decrease in thermal resistance (D60=0·8min). These data indicate thatL. monocytogenes has a thermal resistance in Liver Sausage comparable to that observed in other food systems.
Nicole Pavio - One of the best experts on this subject based on the ideXlab platform.
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foodborne transmission of hepatitis e virus from raw pork Liver Sausage france
Emerging Infectious Diseases, 2014Co-Authors: C Renou, Annemarie Roqueafonso, Nicole PavioAbstract:To the Editor: The number of sporadic autochthonous cases of acute hepatitis E is increasing in many industrialized countries (1). These cases involve hepatitis E virus (HEV) genotypes 3 and 4, which are zoonotic. Although risk for foodborne transmission from pork is now recognized, we report here direct HEV transmission through ingestion of raw pig Liver Sausages (figatellu [plural: figatelli]) in southeastern France. The index case-patient was a 45-year-old woman from Hyeres (southeastern France) who had no underlying medical condition. She visited her general practitioner on December 17, 2013, reporting 3 days of weakness. Acute hepatitis was diagnosed 2 days later on the basis of elevated Liver enzymes (alanine aminotransferase 1,265 IU/L [reference <35 IU/L]) and bilirubin (65 μmol/L [reference <17 μmol/L]). Serum markers for acute hepatitis A, B, and C; cytomegalovirus; and Epstein-Barr virus were negative. Jaundice appeared on December 19, and the patient was referred to the Medical Unit of Hyeres for additional investigations. A serum sample collected on December 20 tested positive for HEV RNA; viral load was 3.3 log10 IU/mL (Ceeram, La Chapelle sur Erdre, France), and IgM and IgG against HEV were found (Wantai, Beijing, China), which led to the diagnosis of acute hepatitis E. The HEV genotype was 3f, as determined from the phylogenetic analysis of a portion of the open reading frame (ORF) 2 (2). The index case-patient recovered by the end of January; HEV viremia was undetectable on January 17, 2014. The index case-patient and her family regularly ate figatelli (raw pork Liver Sausages) made in Corsica. The patient had most recently eaten figatelli at a lunch with 8 family members on October 28, 2013, seven weeks before illness onset. After receiving informed consent, we conducted laboratory investigations of samples from the other family members; tests included HEV serology and HEV RNA detection in serum and fecal samples. Samples were obtained from family members during January 8–21, 2014 (41–54 days after the lunch). Positive HEV IgM and detectable HEV RNA were found in the serum of the index case-patient’s daughter, who was asymptomatic. Because the sample was tested 10 weeks after the family lunch, the daughter’s HEV viral load was too low to enable sequence characterization and clustering of HEV strains. Three other family members were IgG positive for HEV, indicating previous HEV infection. Leftover Sausages had been kept frozen and were available for HEV testing. HEV RNA was detectable from the leftover Sausages, and HEV sequences were amplified in 2 different genomic regions (ORF1: RNA-dependent RNA polymerase and ORF2), as described previously (2). Comparison with the index case-patient’s sequences showed 100% nt identity for both regions (Figure). Samples of food and samples from the index case-patient were analyzed in 2 independent laboratories to avoid any cross-contamination. The level of contamination of the figatellu was ≈4.8 104 copies of HEV RNA/g of Sausage (3). Figure Phylogenetic analysis of partial open reading frame (ORF) 2 and ORF1 sequences of hepatitis E virus (HEV). Phylogenetic trees were constructed in MEGA6 software (http://www.megasoftware.net) by using the neighbor-joining method from a Kimura 2-parameter ... Figatellu, a dried Sausage, contains 30% pork Liver and no heating step occurs during its manufacture. Usually deep cooking is recommended on the package, but consumers might not follow the cooking recommendation; also, figatelli can be sold in small local shops with no label. In the instance reported here, the figatellu was sold without any warning label and was eaten raw. That HEV was transmitted through ingestion of contaminated food is supported by the following evidence. First, 3 case reports have provided direct evidence of HEV transmission through ingestion of contaminated animal food products with identical or near identical sequences between the patients and the contaminated food they ate. Two cases occurred in the early 2000s in Japan through consumption of grilled wild boar (4) or sashimi of Sika deer (5); the third, reported recently in Spain, was transmitted through ingestion of pig meat (6). Second, HEV widely infects domestic pigs and wild boar (7). Third, swine and human HEV strains have genetic similarities and, in some cases, are indistinguishable (1). Fourth, in Marseille, France, a case–control study identified ingestion of figatellu as a risk factor for HEV infection. Genetic similarities were found between sequences isolated from patients with autochthonous hepatitis E and nonrelated figatelli purchased in the same region (8). Finally, infectious virus, replicating in a 3-dimensional culture system, was identified in a HEV RNA-positive figatellu (9). In the present study, the homology between sequences recovered from the index case-patient and those recovered from leftovers of figatellu provides additional proof of HEV foodborne transmission in a Western country. In France, information about the risk for HEV transmission through the ingestion of such delicatessen was published by French authorities in 2010 (10), but the present case demonstrates that public education and warning, or larger and more explicit labels on the package, must be improved to reduce the risk for HEV exposure.
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DISPATCHES Hepatitis E Virus in Pork Liver Sausage, France
2013Co-Authors: Ra Berto, Nicole Pavio, Reimar Johne, Sylvia Grierson, Renate Hakze-van Der Honing, Francesca Martelli, Jochen Reetz, Rainer G. Ulrich, Wim H. M, Van PoelAbstract:We investigated viability of hepatitis E virus (HEV) identified in contaminated pork Liver Sausages obtained from France. HEV replication was demonstrated in 1 of 4 samples by using a 3-dimensional cell culture system. The risk for human infection with HEV by consumption of these Sausages should be considered to be high. Foodborne transmission of hepatitis E virus (HEV) to humans from consumption of undercooked pig Liver and deer meat has been reported in Japan (1–3). In addition, commercial pig Livers purchased from local grocery stores in Japan, the United States, and Europe were contaminated with HEV (4–6). Epidemiologic and PCR results linked a cluster of autochthonous acute hepatitis E cases to ingestion of raw figatelli, which is a dried, cold-smoked Sausage containing ≈30 % pig Liver (7). We investigated the viability of HEV in pork Liver Sausages produced in France. The Study Four samples of pork Liver Sausage (designated Sausages A–D) collected at the final production stage from 4 independent manufacturers in 3 locations in southern France were found to be HEV positive by using realtime reverse transcription PCR (RT-PCR). Samples were tested in 2 institutes, the Animal Health and Veterinar
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hepatitis e virus in pork Liver Sausage france
Emerging Infectious Diseases, 2012Co-Authors: A Berto, Nicole Pavio, Reimar Johne, Renate Hakze-van Der Honing, Francesca Martelli, Jochen Reetz, Rainer G. Ulrich, Sylvia S Grierson, Wim H M Van Der Poel, Malcolm BanksAbstract:We investigated viability of hepatitis E virus (HEV) identified in contaminated pork Liver Sausages obtained from France. HEV replication was demonstrated in 1 of 4 samples by using a 3-dimensional cell culture system. The risk for human infection with HEV by consumption of these Sausages should be considered to be high.
Jacques Izopet - One of the best experts on this subject based on the ideXlab platform.
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a nationwide survey of hepatitis e viral infection in french blood donors
Hepatology, 2016Co-Authors: Jean Michel Mansuy, Pierre Gallian, Chloe Dimeglio, Karine Saune, Catherine Arnaud, Bertrand Pelletier, P Morel, Dominique Legrand, Pierre Tiberghien, Jacques IzopetAbstract:Most cases of hepatitis E viral (HEV) infection in developed countries are autochthonous. Nevertheless, the reported seroprevalence of HEV varies greatly depending on the geographical area and the performance of the immunoassay used. We used validated assays to determine the prevalence of anti-HEV immunoglobulin G (IgG) and IgM among 10,569 French blood donors living in mainland France and three overseas areas. Epidemiological information was collected using a specific questionnaire. We found an overall IgG seroprevalence of 22.4% (8%-86.4%) depending on the geographical area (P < 0.001). The presence of anti-HEV IgG was associated with increasing age (P < 0.001) and eating pork meat (P = 0.03), pork Liver Sausages (P < 0.001), game meat (P < 0.01), offal (P < 0.001), and oysters (P = 0.02). Conversely, drinking bottled water was associated with a lower rate of anti-HEV IgG (P = 0.02). Overall IgM seroprevalence was 1% (0%-4.6%). The frequency of anti-HEV IgM was higher in donors living in a high anti-HEV IgG seroprevalence area (1.9% versus 0.7%, P < 0.001) and in those eating pork Liver Sausage (1.4% versus 0.7%, P < 0.01), pâte (1% versus 0.4, P = 0.04), and wild boar (1.3% versus 0.7%, P < 0.01). Conclusion: HEV is endemic in France and hyperendemic in some areas; eating habits alone cannot totally explain the exposure to HEV, and contaminated water could contribute to the epidemiology of HEV infection in France. (Hepatology 2016;63:1145–1154)
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a nationwide survey of hepatitis e virus infection in french blood donors
Hepatology, 2016Co-Authors: Jean Michel Mansuy, Pierre Gallian, Chloe Dimeglio, Karine Saune, Catherine Arnaud, Bertrand Pelletier, P Morel, Dominique Legrand, Pierre Tiberghien, Jacques IzopetAbstract:Most cases of hepatitis E viral (HEV) infection in developed countries are autochthonous. Nevertheless, the reported seroprevalence of HEV varies greatly depending on the geographical area and the performance of the immunoassay used. We used validated assays to determine the prevalence of anti-HEV immunoglobulin G (IgG) and IgM among 10,569 French blood donors living in mainland France and three overseas areas. Epidemiological information was collected using a specific questionnaire. We found an overall IgG seroprevalence of 22.4% (8%-86.4%) depending on the geographical area (P < 0.001). The presence of anti-HEV IgG was associated with increasing age (P < 0.001) and eating pork meat (P = 0.03), pork Liver Sausages (P < 0.001), game meat (P < 0.01), offal (P < 0.001), and oysters (P = 0.02). Conversely, drinking bottled water was associated with a lower rate of anti-HEV IgG (P = 0.02). Overall IgM seroprevalence was 1% (0%-4.6%). The frequency of anti-HEV IgM was higher in donors living in a high anti-HEV IgG seroprevalence area (1.9% versus 0.7%, P < 0.001) and in those eating pork Liver Sausage (1.4% versus 0.7%, P < 0.01), pâte (1% versus 0.4, P = 0.04), and wild boar (1.3% versus 0.7%, P < 0.01). Conclusion: HEV is endemic in France and hyperendemic in some areas; eating habits alone cannot totally explain the exposure to HEV, and contaminated water could contribute to the epidemiology of HEV infection in France. (Hepatology 2016;63:1145–1154)
Leora A Shelef - One of the best experts on this subject based on the ideXlab platform.
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behaviour of foodborne pathogens in cooked Liver Sausage containing lactates
Food Microbiology, 1995Co-Authors: Leora A Shelef, V PotluriAbstract:Previous reports from our laboratory showed sensitivity of Listeria monocytogenes to lactates in cooked pork Liver Sausage. Further studies were undertaken to explain the antilisterial effects and to examine the sensitivity of Escherichia coli O157:H7 and Salmonella typhimurium strains to lactates. To determine the effect of heat treatment on the antilisterial activity during storage at 5 and 20°C, 3% sodium or calcium lactate (NaL or CaL) were added to Sausage emulsion, followed by (1) sterilization (121°C, 15 min); (2) processing in a water bath to internal temperature of 70°C; or (3) added to ready-to-eat Sausage (no additional heat treatment). Inhibition of L. monocytogenes strain Scott A was highest after heat sterilization and storage at 5°C. Growth of S. typhimurium and E. coli O157:H7 was abated in sterilized Sausage by 3% NaL and CaL. Changes in log cfu g −1 after 4 days at 20°C were (1) L. monocytogenes : control, 5·96; 3% NaL, −0·17; 3% CaL, −0·77; (2) E. coli : control, 4·01; NaL, 0·34; CaL, −0·06; (3) S. typhimurium : control, 3·92; NaL, 1·14; CaL, 0·92. While CaL was consistently more effective than NaL, examination of other calcium salts (carbonate, chloride, citrate and phosphate, dibasic) confirmed that lactate is the principal antibacterial factor.
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sensitivity of listeria monocytogenes to rosemary rosmarinus officinalis l
Food Microbiology, 1994Co-Authors: V A Pandit, Leora A ShelefAbstract:There are limited reports on antilisterial activities of spices and herbs in culture media and fewer still in foods. The present study was undertaken to identify spices that possess antilisterial properties and to evaluate effects in media and food. Of 18 spices screened on BHI agar (48 h, 35°C), only rosemary (≥0·5%, w/v) and cloves (≥1%, w/v) were listericidal. Tests were expanded with rosemary to include also its essential oil and four of the major oil constituents, oleoresin, encapsulated oil, and antioxidant extract of rosemary. Effects on Listeria monocytogenes strain Scott A in BHI broth were examined after 24 and 48 h at 35°C. The inhibitory concentrations of rosemary oil were 10 wl/100 ml broth. Of the major constituents of rosemary oil (cineole, borneole, α-pinene and camphor), only α-pinene (0·1 wl/100 ml) delayed listerial growth. The oleoresin, the encapsulated oil, and the antioxidant extract were also antilisterial (100 mg, ≥ 1 g and 0·02 g per 100 ml, respectively). The antilisterial activity of the aqueous extract of rosemary was considerably lower than that of the ground herb or the ethanolic extract. Addition of 0·5% finely ground rosemary or 1% rosemary oil to ready-to-eat pork Liver Sausage prior to cooking delayed listerial growth during refrigerated storage. The encapsulated oil (5%) and the antioxidant extract (0·3-0·5%) inhibited growth of listeriae, whereas the oil (1%) was ineffective.
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antilisterial activity of sodium potassium or calcium lactate in pork Liver Sausage
Journal of Food Safety, 1993Co-Authors: Rivian A Weaver, Leora A ShelefAbstract:The antilisterial activity of sodium, potassium or calcium lactate was tested in pork Liver Sausage (55% moisture, 2% sodium chloride). Lactate levels of 2, 3 or 4% (w/w) were used and the Sausage was sterilized and inoculated with 104–105 cells/g of Listeria monocytogenes strain Scott A. Enhanced inhibitory effects of the organism were observed with increasing concentrations of the salts at two storage temperatures. At 20C, cell numbers in the controls increased by 5 log cycles after 10 days. The change in log CFU/g in samples treated with 4% of the lactate salts was: sodium, 1.4; potassium, 1.35, and calcium, -1.33. At 5C, cell numbers after 50 days of storage increased by 4.5 log cycles in controls, and changes in log CFU/g in samples treated with 3% lactate were: sodium, 0.88; potassium, -0.67, and calcium, -1.49. Increasing the sodium chloride content in the product enhanced the inhibitory effects. While L. monocytogenes grew better in heat processed (water bath) than in heat sterilized Sausage, cell growth was suppressed during refrigerated storage by 3% of each of the lactate salts, and the effect of the calcium salt was superior to that of either the sodium or the potassium salt. Although addition of lactates to the Sausage lowered the water activity, the change was not sufficient to account for the antilisterial activity of these salts.
Samuel A. Palumbo - One of the best experts on this subject based on the ideXlab platform.
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Thermal destruction of Listeria monocytogenes during Liver Sausage processing
Food Microbiology, 1993Co-Authors: Samuel A. Palumbo, C. Turner-jones, Benne S. Marmer, Saumya Bhaduri, Laura L Zaika, James L. Smith, Aaron C. WilliamsAbstract:Abstract We studied the inactivation of Listeria monocytogenes during the thermal processing of Liver Sausage. Liver Sausage emulsion was prepared and inoculated with L. monocytogenes Scott A to yield an initial population of c. 10 9 g -1 . The inoculated emulsion was stuffed into large diameter, moisture-proof fibrous casings and cooked in a smokehouse. Individual Sausages were removed as the product reached various predetermined internal temperatures, and duplicate core samples were analyzed for viable L. monocytogenes by surface plating onto tryptose agar. The viable count remained unchanged in product heated to 140°F. In product heated to 145°F, the number of viable L. monocytogenes decreased and at 155°F, no viable L. monocytogenes were detected. Thus, Liver Sausage and other large diameter non-fermented Sausage product heated to 155°F should be free of viable L. monocytogenes.
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thermal destruction oflisteria monocytogenes in Liver Sausage slurry
Food Microbiology, 1991Co-Authors: Saumya Bhaduri, Benne S. Marmer, Laura L Zaika, James L. Smith, Samuel A. Palumbo, Phillip W Smith, C Turnerjones, Robert L Buchanan, Aaron C. WilliamsAbstract:Abstract Thermal destruction ofListeria monocytogenes was determined in a Liver Sausage slurry (1:1, Liver Sausage batter and water) using a submerged ampule technique.D-values forL. monocytogenes Scott A grown at 37°C were 8·9 min at 57·2°C, 2·4 min at 60·0°C, and 1·1 min at 62·8°C (Z=6·2°C) based on analysis of the linear portion of the survivor curves.D-values of 6·6, 1·6, and 0·4 min (Z=4·65°C) were obtained when the data were analyzed using non-linear techniques.L. monocytogenes strain V7 (D60=1.0min) was more thermosensitive than Scott A (D60=1·6min) or HO-VJ-S (D60=1·6min). When Scott A was grown at 19°C, there was a decrease in thermal resistance (D60=0·8min). These data indicate thatL. monocytogenes has a thermal resistance in Liver Sausage comparable to that observed in other food systems.