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Eduardo F. Escartín - One of the best experts on this subject based on the ideXlab platform.
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changes in the effectiveness of chlorine treatments during colonization of Salmonella Montevideo on tomatoes
Journal of Food Safety, 2010Co-Authors: Montserrat H. Iturriaga, Eduardo F. EscartínAbstract:Inactivation of pathogens in produce is an essential approach for mitigating the risk of disease. A study was undertaken to compare the efficacy of chlorine to kill Salmonella Montevideo cells during colonization on the surface of tomatoes. Tomatoes (Lycopersicum esculentum) were spot-inoculated with 100 µL (ca. 8 log cfu) of S. Montevideo. To promote attachment, inoculated fruits were incubated for 90 min at 22C, then washed to remove unattached cells and stored at 30C and 97% relative humidity for up to 10 days. Periodically, tomatoes were treated with chlorine (1000 or 200 mg/L) or water (control). On day 0, treatments with 1000 or 200 mg/L of chlorine, and water reduced the pathogen population by approximately 5.0, 4.5 and 0.4 log cfu/tomato, respectively. The inactivation efficacy of the sanitizers decreased as the storage time elapsed. By the 7th day, the populations recovered from tomatoes treated with water and disinfectants were not significantly different (P < 0.5). PRACTICAL APPLICATIONS This study clearly shows how the effectiveness of chlorine is modified when treatments are applied to tomatoes several days after the contamination with a human pathogen took place. The diminished effect of disinfection treatments suggests that microorganisms colonizing on surfaces become more resistant to germicides, and that biofilms may provide protective sites, or both. The results also reinforce the concept that once contaminated, bacterial pathogens can persist on tomatoes throughout a normal distribution time.
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CHANGES IN THE EFFECTIVENESS OF CHLORINE TREATMENTS DURING COLONIZATION OF Salmonella Montevideo ON TOMATOES
Journal of Food Safety, 2010Co-Authors: Montserrat H. Iturriaga, Eduardo F. EscartínAbstract:Inactivation of pathogens in produce is an essential approach for mitigating the risk of disease. A study was undertaken to compare the efficacy of chlorine to kill Salmonella Montevideo cells during colonization on the surface of tomatoes. Tomatoes (Lycopersicum esculentum) were spot-inoculated with 100 µL (ca. 8 log cfu) of S. Montevideo. To promote attachment, inoculated fruits were incubated for 90 min at 22C, then washed to remove unattached cells and stored at 30C and 97% relative humidity for up to 10 days. Periodically, tomatoes were treated with chlorine (1000 or 200 mg/L) or water (control). On day 0, treatments with 1000 or 200 mg/L of chlorine, and water reduced the pathogen population by approximately 5.0, 4.5 and 0.4 log cfu/tomato, respectively. The inactivation efficacy of the sanitizers decreased as the storage time elapsed. By the 7th day, the populations recovered from tomatoes treated with water and disinfectants were not significantly different (P
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Animal and environmental impact on the presence and distribution of Salmonella and Escherichia coli in hydroponic tomato greenhouses.
Journal of food protection, 2008Co-Authors: R Leopoldo Orozco, Montserrat H. Iturriaga, Mark L. Tamplin, Pina M. Fratamico, Jeffrey E. Call, John B. Luchansky, Eduardo F. EscartínAbstract:From 2003 to 2004, we studied the impact of environmental influences on the microbiological quality of a hydroponic tomato farm. The presence of Salmonella was investigated on 906 samples of tomatoes and 714 environmental samples. The farm comprised 14 greenhouses and a technologically advanced packinghouse, and operated under a sanitary agricultural practices plan. The objective of the present study was to determine the operating sources of contamination. During the course of the study, two independent natural events affected the farm. In 2003, water runoff entered some of the greenhouses. A year later, wild animals (opossums, mice, and sparrows) gained entry into several of the greenhouses. Salmonella and Escherichia coli were found in samples of tomatoes, water puddles, soil, shoes, and the feces of local wild and farm animals. Salmonella Montevideo, Salmonella Newport, and strains of the F serogroup were isolated from tomatoes. Almost all of the Salmonella Newport strains were isolated from samples collected during or immediately after the flood. Analysis by pulsed-field gel electrophoresis revealed that some Salmonella Montevideo isolates from tomatoes, opossums, and mice displayed identical XbaI or AvrII patterns, suggesting that these wild animals represented one source of contamination. F serogroup strains were found mostly on samples of goat feces and personnel shoes when standard working practices were in place. Shoes were found to be an important vehicle for dissemination of Salmonella into the greenhouses. The level of protection provided by hydroponic greenhouses does not exclude the eventuality that enteric pathogenic bacteria can gain access through various avenues.
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Colonization of tomatoes by Salmonella Montevideo is affected by relative humidity and storage temperature.
Journal of food protection, 2007Co-Authors: Montserrat H. Iturriaga, Mark L. Tamplin, Eduardo F. EscartínAbstract:The influences of the relative humidity (RH) and storage temperature on the colonization of tomato surfaces by Salmonella Montevideo were studied. Red, ripe tomatoes (Lycopersicon esculentum) were spot inoculated in three separate trials with 100 l (approximately 106 CFU) of Salmonella Montevideo and stored for 90 min at 22C under 97% RH to facilitate attachment of cells to the blossom end of tomato surfaces. Following this attachment step, tomatoes were washed to remove loosely adhered cells and then stored at 22 or 30C for up to 10 days under RH of 60, 75, 85, or 97%. At 0, 0.4, 1, 4, 7, and 10 days of storage, three tomatoes were individually hand massaged in 50 ml of 0.1% peptone water and the washes were separately analyzed to enumerate populations of Salmonella Montevideo. The number of Salmonella Montevideo cells attached after 90 min at 22C was 3.8 log CFU per tomato; this level was determined to be the initial colonizing population. After 10 days of storage at 30C, the Salmonella Montevideo population increased to 0.7, 1.0, 1.2, and 2.2 log CFU per tomato at 60, 75, 85, and 97% RH, respectively. A similar trend was observed at 22C, although populations were lower than at 30C. Scanning electron micrographs of tomato cuticles after storage revealed a well-defined biofilm containing bacteria. These findings reinforce the importance of maintaining stored tomatoes at temperatures that do not support growth of pathogenic bacteria and demonstrate the growth-promoting effects of high humidity.
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Effect of inoculum size, relative humidity, storage temperature, and ripening stage on the attachment of Salmonella Montevideo to tomatoes and tomatillos.
Journal of food protection, 2003Co-Authors: Montserrat H. Iturriaga, Larry R. Beuchat, Eduardo F. Escartín, Ramón Álvar Martínez-penicheAbstract:The influence of inoculum populations and environmental factors on attachment of Salmonella Montevideo to the surface of tomatoes and tomatillos was evaluated. To study the effect of inoculum size, red, ripe tomatoes were spot-inoculated with bacterial suspensions (105 and 108 CFU/fruit) and stored at 22°C under 100% relative humidity. The effects of temperature (12, 22, and 30°C) and relative humidity (75, 85, and 97%) on attachment of the pathogen (107 CFU/fruit) to tomatoes (red and green) and ripe tomatillos were also evaluated. Inoculated fruits were stored for 90 min at all combinations of temperature and relative humidity, and after rinsing with water, the number of cells attached to the surface was determined. Salmonella Montevideo attached to the surface of tomatoes within 90 min. A direct correlation between the number of attached cells and the population in the inoculum was observed. The percentage of cells that attached immediately after inoculation was approximately 0.3% for the three test pr...
Montserrat H. Iturriaga - One of the best experts on this subject based on the ideXlab platform.
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changes in the effectiveness of chlorine treatments during colonization of Salmonella Montevideo on tomatoes
Journal of Food Safety, 2010Co-Authors: Montserrat H. Iturriaga, Eduardo F. EscartínAbstract:Inactivation of pathogens in produce is an essential approach for mitigating the risk of disease. A study was undertaken to compare the efficacy of chlorine to kill Salmonella Montevideo cells during colonization on the surface of tomatoes. Tomatoes (Lycopersicum esculentum) were spot-inoculated with 100 µL (ca. 8 log cfu) of S. Montevideo. To promote attachment, inoculated fruits were incubated for 90 min at 22C, then washed to remove unattached cells and stored at 30C and 97% relative humidity for up to 10 days. Periodically, tomatoes were treated with chlorine (1000 or 200 mg/L) or water (control). On day 0, treatments with 1000 or 200 mg/L of chlorine, and water reduced the pathogen population by approximately 5.0, 4.5 and 0.4 log cfu/tomato, respectively. The inactivation efficacy of the sanitizers decreased as the storage time elapsed. By the 7th day, the populations recovered from tomatoes treated with water and disinfectants were not significantly different (P < 0.5). PRACTICAL APPLICATIONS This study clearly shows how the effectiveness of chlorine is modified when treatments are applied to tomatoes several days after the contamination with a human pathogen took place. The diminished effect of disinfection treatments suggests that microorganisms colonizing on surfaces become more resistant to germicides, and that biofilms may provide protective sites, or both. The results also reinforce the concept that once contaminated, bacterial pathogens can persist on tomatoes throughout a normal distribution time.
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CHANGES IN THE EFFECTIVENESS OF CHLORINE TREATMENTS DURING COLONIZATION OF Salmonella Montevideo ON TOMATOES
Journal of Food Safety, 2010Co-Authors: Montserrat H. Iturriaga, Eduardo F. EscartínAbstract:Inactivation of pathogens in produce is an essential approach for mitigating the risk of disease. A study was undertaken to compare the efficacy of chlorine to kill Salmonella Montevideo cells during colonization on the surface of tomatoes. Tomatoes (Lycopersicum esculentum) were spot-inoculated with 100 µL (ca. 8 log cfu) of S. Montevideo. To promote attachment, inoculated fruits were incubated for 90 min at 22C, then washed to remove unattached cells and stored at 30C and 97% relative humidity for up to 10 days. Periodically, tomatoes were treated with chlorine (1000 or 200 mg/L) or water (control). On day 0, treatments with 1000 or 200 mg/L of chlorine, and water reduced the pathogen population by approximately 5.0, 4.5 and 0.4 log cfu/tomato, respectively. The inactivation efficacy of the sanitizers decreased as the storage time elapsed. By the 7th day, the populations recovered from tomatoes treated with water and disinfectants were not significantly different (P
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Animal and environmental impact on the presence and distribution of Salmonella and Escherichia coli in hydroponic tomato greenhouses.
Journal of food protection, 2008Co-Authors: R Leopoldo Orozco, Montserrat H. Iturriaga, Mark L. Tamplin, Pina M. Fratamico, Jeffrey E. Call, John B. Luchansky, Eduardo F. EscartínAbstract:From 2003 to 2004, we studied the impact of environmental influences on the microbiological quality of a hydroponic tomato farm. The presence of Salmonella was investigated on 906 samples of tomatoes and 714 environmental samples. The farm comprised 14 greenhouses and a technologically advanced packinghouse, and operated under a sanitary agricultural practices plan. The objective of the present study was to determine the operating sources of contamination. During the course of the study, two independent natural events affected the farm. In 2003, water runoff entered some of the greenhouses. A year later, wild animals (opossums, mice, and sparrows) gained entry into several of the greenhouses. Salmonella and Escherichia coli were found in samples of tomatoes, water puddles, soil, shoes, and the feces of local wild and farm animals. Salmonella Montevideo, Salmonella Newport, and strains of the F serogroup were isolated from tomatoes. Almost all of the Salmonella Newport strains were isolated from samples collected during or immediately after the flood. Analysis by pulsed-field gel electrophoresis revealed that some Salmonella Montevideo isolates from tomatoes, opossums, and mice displayed identical XbaI or AvrII patterns, suggesting that these wild animals represented one source of contamination. F serogroup strains were found mostly on samples of goat feces and personnel shoes when standard working practices were in place. Shoes were found to be an important vehicle for dissemination of Salmonella into the greenhouses. The level of protection provided by hydroponic greenhouses does not exclude the eventuality that enteric pathogenic bacteria can gain access through various avenues.
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Colonization of tomatoes by Salmonella Montevideo is affected by relative humidity and storage temperature.
Journal of food protection, 2007Co-Authors: Montserrat H. Iturriaga, Mark L. Tamplin, Eduardo F. EscartínAbstract:The influences of the relative humidity (RH) and storage temperature on the colonization of tomato surfaces by Salmonella Montevideo were studied. Red, ripe tomatoes (Lycopersicon esculentum) were spot inoculated in three separate trials with 100 l (approximately 106 CFU) of Salmonella Montevideo and stored for 90 min at 22C under 97% RH to facilitate attachment of cells to the blossom end of tomato surfaces. Following this attachment step, tomatoes were washed to remove loosely adhered cells and then stored at 22 or 30C for up to 10 days under RH of 60, 75, 85, or 97%. At 0, 0.4, 1, 4, 7, and 10 days of storage, three tomatoes were individually hand massaged in 50 ml of 0.1% peptone water and the washes were separately analyzed to enumerate populations of Salmonella Montevideo. The number of Salmonella Montevideo cells attached after 90 min at 22C was 3.8 log CFU per tomato; this level was determined to be the initial colonizing population. After 10 days of storage at 30C, the Salmonella Montevideo population increased to 0.7, 1.0, 1.2, and 2.2 log CFU per tomato at 60, 75, 85, and 97% RH, respectively. A similar trend was observed at 22C, although populations were lower than at 30C. Scanning electron micrographs of tomato cuticles after storage revealed a well-defined biofilm containing bacteria. These findings reinforce the importance of maintaining stored tomatoes at temperatures that do not support growth of pathogenic bacteria and demonstrate the growth-promoting effects of high humidity.
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Effect of inoculum size, relative humidity, storage temperature, and ripening stage on the attachment of Salmonella Montevideo to tomatoes and tomatillos.
Journal of food protection, 2003Co-Authors: Montserrat H. Iturriaga, Larry R. Beuchat, Eduardo F. Escartín, Ramón Álvar Martínez-penicheAbstract:The influence of inoculum populations and environmental factors on attachment of Salmonella Montevideo to the surface of tomatoes and tomatillos was evaluated. To study the effect of inoculum size, red, ripe tomatoes were spot-inoculated with bacterial suspensions (105 and 108 CFU/fruit) and stored at 22°C under 100% relative humidity. The effects of temperature (12, 22, and 30°C) and relative humidity (75, 85, and 97%) on attachment of the pathogen (107 CFU/fruit) to tomatoes (red and green) and ripe tomatillos were also evaluated. Inoculated fruits were stored for 90 min at all combinations of temperature and relative humidity, and after rinsing with water, the number of cells attached to the surface was determined. Salmonella Montevideo attached to the surface of tomatoes within 90 min. A direct correlation between the number of attached cells and the population in the inoculum was observed. The percentage of cells that attached immediately after inoculation was approximately 0.3% for the three test pr...
Jonathan Lalsiamthara - One of the best experts on this subject based on the ideXlab platform.
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Corrigendum: Pathogenic traits of Salmonella Montevideo in experimental infections in vivo and in vitro.
Scientific reports, 2017Co-Authors: Jonathan Lalsiamthara, John Hwa LeeAbstract:Scientific Reports 7: Article number: 46232; published online: 07 April 2017; updated: 04 May 2017 The Acknowledgements section in this Article has been omitted. It should read: "Acknowledgements This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MISP) (No.
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Correction: Corrigendum: Pathogenic traits of Salmonella Montevideo in experimental infections in vivo and in vitro
Scientific Reports, 2017Co-Authors: Jonathan Lalsiamthara, John Hwa LeeAbstract:Scientific Reports 7: Article number: 46232; published online: 07 April 2017; updated: 04 May 2017 The Acknowledgements section in this Article has been omitted. It should read: “Acknowledgements This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MISP) (No.
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Pathogenic traits of Salmonella Montevideo in experimental infections in vivo and in vitro
Scientific Reports, 2017Co-Authors: Jonathan LalsiamtharaAbstract:Salmonella serovar Montevideo (SM) is frequently associated with human Salmonella infections and causes gastrointestinal disease, cases are common particularly among individuals who come in close contact with live poultry or poultry meat products. To characterize SM disease in chickens, the pathogenic traits and tissue predilections of the disease were investigated. Dissemination of fluorescent-tagged SM (JOL1575GFP) was monitored after oral and intramuscular mock infections of specific-pathogen-free chickens. The spleen was predominantly affected by intramuscular infection while the cecum, spleen, and minimally liver were affected by oral infection. No conspicuous illness was observed in infected birds, and histopathological examination showed minimal damage of the intestinal epithelium and splenic parenchyma though SM was readily isolated from these tissues. Levels of SM internalization by primary chicken peritoneal macrophages were similar to that of Salmonella Typhimurium. SM was more sensitive to chicken than rabbit serum complement killing. Internal egg contamination of SM mock infected layers also occurred at trace levels and lasted for a week after inoculation. This study also confirmed that SM infection in chickens is sub-clinical and asymptomatic, which suggests that latent asymptomatic carriers may excrete a large number of bacteria and transmit the pathogen by contaminating water or food sources.
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A live attenuated mutant of Salmonella Montevideo triggers IL-6, IFN-γ and IL-12 cytokines that co-related with humoral and cellular immune responses required for reduction of challenge bacterial load in experimental chickens.
Comparative immunology microbiology and infectious diseases, 2016Co-Authors: Jonathan Lalsiamthara, John Hwa LeeAbstract:A live attenuated Salmonella enterica serovar Montevideo (SM) mutant JOL1599 was constructed by deletion of virulence-associated genes. The protective efficacy and immune response profiles of chickens immunized with JOL1599 were investigated. Immunized chickens demonstrated significant increases in plasma IgG and lymphocyte proliferative responses (P≤0.05). Increased levels of IL-6, INF-γ, and IL-12 were also observed. Immunized birds strongly responded to infection by rapid stimulation of a CD4+ subset of T cells. Organ bacterial recovery assay revealed a significant reduction in the challenge strain among immunized birds. Multiple doses of JOL1599 enhanced the immune responses of the birds as revealed by ascending trends of the immunological profiles. These findings indicate that immunization of chickens with JOL1599 may provide protection against Salmonella Montevideo infection via induction of IL-6, INF-γ, and IL-12 protective cytokines, which in turn triggers conducive humoral and cell-mediated immune responses.
Mark L. Tamplin - One of the best experts on this subject based on the ideXlab platform.
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Animal and environmental impact on the presence and distribution of Salmonella and Escherichia coli in hydroponic tomato greenhouses.
Journal of food protection, 2008Co-Authors: R Leopoldo Orozco, Montserrat H. Iturriaga, Mark L. Tamplin, Pina M. Fratamico, Jeffrey E. Call, John B. Luchansky, Eduardo F. EscartínAbstract:From 2003 to 2004, we studied the impact of environmental influences on the microbiological quality of a hydroponic tomato farm. The presence of Salmonella was investigated on 906 samples of tomatoes and 714 environmental samples. The farm comprised 14 greenhouses and a technologically advanced packinghouse, and operated under a sanitary agricultural practices plan. The objective of the present study was to determine the operating sources of contamination. During the course of the study, two independent natural events affected the farm. In 2003, water runoff entered some of the greenhouses. A year later, wild animals (opossums, mice, and sparrows) gained entry into several of the greenhouses. Salmonella and Escherichia coli were found in samples of tomatoes, water puddles, soil, shoes, and the feces of local wild and farm animals. Salmonella Montevideo, Salmonella Newport, and strains of the F serogroup were isolated from tomatoes. Almost all of the Salmonella Newport strains were isolated from samples collected during or immediately after the flood. Analysis by pulsed-field gel electrophoresis revealed that some Salmonella Montevideo isolates from tomatoes, opossums, and mice displayed identical XbaI or AvrII patterns, suggesting that these wild animals represented one source of contamination. F serogroup strains were found mostly on samples of goat feces and personnel shoes when standard working practices were in place. Shoes were found to be an important vehicle for dissemination of Salmonella into the greenhouses. The level of protection provided by hydroponic greenhouses does not exclude the eventuality that enteric pathogenic bacteria can gain access through various avenues.
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Colonization of tomatoes by Salmonella Montevideo is affected by relative humidity and storage temperature.
Journal of food protection, 2007Co-Authors: Montserrat H. Iturriaga, Mark L. Tamplin, Eduardo F. EscartínAbstract:The influences of the relative humidity (RH) and storage temperature on the colonization of tomato surfaces by Salmonella Montevideo were studied. Red, ripe tomatoes (Lycopersicon esculentum) were spot inoculated in three separate trials with 100 l (approximately 106 CFU) of Salmonella Montevideo and stored for 90 min at 22C under 97% RH to facilitate attachment of cells to the blossom end of tomato surfaces. Following this attachment step, tomatoes were washed to remove loosely adhered cells and then stored at 22 or 30C for up to 10 days under RH of 60, 75, 85, or 97%. At 0, 0.4, 1, 4, 7, and 10 days of storage, three tomatoes were individually hand massaged in 50 ml of 0.1% peptone water and the washes were separately analyzed to enumerate populations of Salmonella Montevideo. The number of Salmonella Montevideo cells attached after 90 min at 22C was 3.8 log CFU per tomato; this level was determined to be the initial colonizing population. After 10 days of storage at 30C, the Salmonella Montevideo population increased to 0.7, 1.0, 1.2, and 2.2 log CFU per tomato at 60, 75, 85, and 97% RH, respectively. A similar trend was observed at 22C, although populations were lower than at 30C. Scanning electron micrographs of tomato cuticles after storage revealed a well-defined biofilm containing bacteria. These findings reinforce the importance of maintaining stored tomatoes at temperatures that do not support growth of pathogenic bacteria and demonstrate the growth-promoting effects of high humidity.
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Elution, Detection, and Quantification of Polio I, Bacteriophages, Salmonella Montevideo, and Escherichia coli O157:H7 from Seeded Strawberries and Tomatoes
Journal of food protection, 2001Co-Authors: Jerzy Lukasik, Michael L. Bradley, Troy M. Scott, Wei-yea Hsu, Samuel R. Farrah, Mark L. TamplinAbstract:This study compared the effect of different physical and chemical treatments of strawberries and tomatoes to determine their ability to recover seeded viral and bacterial pathogens from produce surfaces. Solutions of salts, amino acids, complex media, and detergents were compared as eluants. Phosphate-buffered saline (PBS) containing 0.1% Tween 80 eluted the highest number of seeded microorganisms. Elution with this defined solution was then compared under different conditions of physical agitation. Rotary shaking for 20 min at 36°C eluted higher numbers of viruses and bacteria than did low- or high-speed stomaching. Commercially available and laboratory prepared bacteriological differential media were compared for their ability to recover and distinguish eluted Salmonella Montevideo and Escherichia coli O157:H7 strains from seeded produce. The recovery of seeded bacterial pathogens was low when differential media containing selective ingredients were used (Mac-Conkey sorbitol agar, XLD agar, MacConkey ag...
Larry R. Beuchat - One of the best experts on this subject based on the ideXlab platform.
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Effect of inoculum size, relative humidity, storage temperature, and ripening stage on the attachment of Salmonella Montevideo to tomatoes and tomatillos.
Journal of food protection, 2003Co-Authors: Montserrat H. Iturriaga, Larry R. Beuchat, Eduardo F. Escartín, Ramón Álvar Martínez-penicheAbstract:The influence of inoculum populations and environmental factors on attachment of Salmonella Montevideo to the surface of tomatoes and tomatillos was evaluated. To study the effect of inoculum size, red, ripe tomatoes were spot-inoculated with bacterial suspensions (105 and 108 CFU/fruit) and stored at 22°C under 100% relative humidity. The effects of temperature (12, 22, and 30°C) and relative humidity (75, 85, and 97%) on attachment of the pathogen (107 CFU/fruit) to tomatoes (red and green) and ripe tomatillos were also evaluated. Inoculated fruits were stored for 90 min at all combinations of temperature and relative humidity, and after rinsing with water, the number of cells attached to the surface was determined. Salmonella Montevideo attached to the surface of tomatoes within 90 min. A direct correlation between the number of attached cells and the population in the inoculum was observed. The percentage of cells that attached immediately after inoculation was approximately 0.3% for the three test pr...
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Inactivation of Salmonella Montevideo on Tomatoes by Applying Cellulose-Based Edible Films.
Journal of food protection, 1996Co-Authors: R. Zhuang, Larry R. Beuchat, Manjeet S. Chinnan, R. L. Shewfelt, Yao-wen HuangAbstract:The effect of applying edible coatings to mature-green tomatoes on the survival of Salmonella Montevideo on the surface and in core tissue was investigated. A hydroxypropyl methylcellulose (HPMC) coating significantly (P ≤ 0.05) reduced the number of viable S. Montevideo cells on the surface of tomatoes. However, only about a 2-log-unit reduction was achieved in core tissue. The addition of citric acid, acetic acid, or sorbic acid (0.2 to 0.4%) to HPMC did not substantially enhance bactericidal activity. Concentrations of 72 to 88% ethanol in HPMC were most effective in inactivating S. Montevideo on the surface of tomatoes. Inactivation of S. Montevideo in core tissue was similar when tomatoes were dipped in 55 to 88% ethanol solutions. Application of HPMC coating retarded the rate of loss of firmness and change in color of tomatoes stored at 20°C for up to 18 days.
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effectiveness of trisodium phosphate for killing Salmonella Montevideo on tomatoes
Letters in Applied Microbiology, 1996Co-Authors: R Y Zhuang, Larry R. BeuchatAbstract:R.-Y. ZHUANG AND L.R. BEUCHAT. 1996. A study was undertaken to determine the effectiveness of trisodium phosphate (TSP) in wash water in the inactivation of Salmonella Montevideo on the surface and in core tissue of unwashed, mature-green tomatoes. Complete inactivation on the tomato surface was achieved by dipping tomatoes in a 15% TSP solution for 15s. Significant (P < 0.05) reductions were obtained by dipping tomatoes in a 1% solution for 15s. Populations were significantly reduced in core tissue of tomatoes dipped in 4–15% TSP. However, even at 15%, only about 2 log10 reduction was achieved. Upon ripening, the hue and chroma of tomatoes, indices of colour and brightness, respectively, were unaffected by treatment of TSP. The use of TSP as sanitizing agent in wash water for mature-green tomatoes appears to have good potential.
