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Donghyun Kang - One of the best experts on this subject based on the ideXlab platform.
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synergistic effect of ohmic heating and uv c irradiation for inactivation of escherichia coli o157 h7 salmonella typhimurium and listeria monocytogenes in buffered peptone water and Tomato Juice
Food Control, 2019Co-Authors: Sangsoon Kim, Sanghyun Park, Soohwan Kim, Donghyun KangAbstract:Abstract Hurdle technology, in which preservation techniques are combined, has been of interest to scientists aiming to ensure microbiological food safety. We investigated the synergistic effect of UV-C irradiation and ohmic heating on the inactivation of foodborne pathogens. UV-C irradiation and ohmic heating were applied to buffered peptone water and Tomato Juice inoculated with pathogens simultaneously or sequentially. A synergistic bactericidal effect of the simultaneous treatment was observed against Escherichia coli O157:H7, Salmonella Typhimurium and Listeria monocytogenes. For example, the reductions (log CFU/ml) in E. coli O157:H7 by UV-C irradiation, ohmic heating and simultaneous treatment in Tomato Juice were 0.48, 1.84 and 3.83, respectively. Additive effect was observed for cell membrane damage and lipid oxidation values with the simultaneous treatment Therefore, the proposed synergistic bactericidal mechanism by the simultaneous treatment consists of an acceleration of lipid oxidation, which results in an additive effect on cell membrane pore formation. Sequential treatment of UV-C irradiation after ohmic heating showed the least antibacterial effect in buffered peptone water. On the other hand, the reductions levels of all three pathogens in Tomato Juice were not significantly different between the two treatments regardless of the sequence. The color and lycopene content of Tomato Juice were not significantly deteriorated by either ohmic heating or the simultaneous treatment. Therefore, the combination treatment of UV-C irradiation and ohmic heating including simultaneous and sequential treatments, and regardless of treatment sequence, can be used as an effective hurdle technology ensuring microbiological safety in Juice products.
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application of continuous type pulsed ohmic heating system for inactivation of foodborne pathogens in buffered peptone water and Tomato Juice
Lwt - Food Science and Technology, 2018Co-Authors: Sangsoon Kim, Sanghyun Park, Donghyun KangAbstract:Abstract The purpose of this study was to inactivate Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes by continuous-type pulsed ohmic heating in buffered peptone water (BPW) and Tomato Juice. First, BPW inoculated with the three pathogens were treated at different flow rates (0.2–0.4 LPM) and treatment voltages (9.43–12.14 Vrms/cm). Both heating rate of BPW and reduction rates of pathogens increased corresponding to decreased flow rate. Accordingly, higher numbers of pathogens survived at a higher flow rate (0.4 LPM). Increasing treatment voltage was an effective way to inactivate pathogens at 0.4 LPM, but the heating rate overly accelerated with increasing voltage adversely affecting food quality. Alternatively, increasing initial temperature by preheating can help inactivate pathogens in the early treatment stage without affecting heating rate. From the BPW experiments, we identified that treatment conditions such as flow rate, voltage, and initial temperature are important factors determining pathogen inactivation performance of continuous-type ohmic heating. When applied to Tomato Juice, 5 log reductions of all three pathogens were achieved by applying 12.14Vrms/cm ohmic heating with 0.2 LPM flow rate after preheating sample to 50 °C with a water bath. Quality aspects of color and lycopene content were observed, and a∗ and b∗ values decreased after treatment. Because preheating with additional equipment is inconvenient and occupies valuable space, we developed sequential three cylinder type ohmic heating. By applying the developed sequential ohmic heating, 5 log reductions were achieved for all three pathogens without preheating under the same treatment conditions. Therefore, we concluded that sequential continuous-type ohmic heating can be used utizied effectively to control foodborne pathogens by the Juice industry.
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application of low frequency pulsed ohmic heating for inactivation of foodborne pathogens and ms 2 phage in buffered peptone water and Tomato Juice
Food Microbiology, 2017Co-Authors: Sangsoon Kim, Won Young Choi, Donghyun KangAbstract:The purpose of this study was to inactivate foodborne pathogens effectively by ohmic heating in buffered peptone water and Tomato Juice without causing electrode corrosion and quality degradation. Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes were used as representative foodborne pathogens and MS-2 phage was used as a norovirus surrogate. Buffered peptone water and Tomato Juice inoculated with pathogens were treated with pulsed ohmic heating at different frequencies (0.06–1 kHz). Propidium iodide uptake values of bacterial pathogens were significantly (p < 0.05) larger at 0.06–0.5 kHz than at 1 kHz, and sub-lethal injury of pathogenic bacteria was reduced by decreasing frequency. MS-2 phage was inactivated more effectively at low frequency, and was more sensitive to acidic conditions than pathogenic bacteria. Electrode corrosion and quality degradation of Tomato Juice were not observed regardless of frequency. This study suggests that low frequency pulsed ohmic heating is applicable to inactivate foodborne pathogens effectively without causing electrode corrosion and quality degradation in Tomato Juice.
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effect of continuous ohmic heating to inactivate escherichia coli o157 h7 salmonella typhimurium and listeria monocytogenes in orange Juice and Tomato Juice
Journal of Applied Microbiology, 2012Co-Authors: S Y Lee, Hungu Sagong, S Ryu, Donghyun KangAbstract:Aims: The purpose of this study was to investigate the efficacy of continuous ohmic heating for reducing Escherichia coli O157:H7, Salmonella Typhimurium and Listeria monocytogenes in orange Juice and Tomato Juice. Methods and Results: Orange Juice and Tomato Juice were treated with electric field strengths in the range of 25–40 V cm−1 for different treatment times. The temperature of the samples increased with increasing treatment time and electric field strength. The rate of temperature change for Tomato Juice was higher than for orange Juice at all voltage gradients applied. Higher electric field strength or longer treatment time resulted in a greater reduction of pathogens. Escherichia coli O157:H7 was reduced by more than 5 log after 60-, 90- and 180-s treatments in orange Juice with 40, 35 and 30 V cm−1 electric field strength, respectively. In Tomato Juice, treatment with 25 V cm−1 for 30 s was sufficient to achieve a 5-log reduction in E. coli O157:H7. Similar results were observed in Salm. Typhimurium and L. monocytogenes. The concentration of vitamin C in continuous ohmic heated Juice was significantly higher than in conventionally heated Juice (P < 0·05). Conclusions: Continuous ohmic heating can be effective in killing foodborne pathogens on orange Juice and Tomato Juice with lower degradation of quality than conventional heating. Significance and Impact of the Study: These results suggest that continuous ohmic heating might be effectively used to pasteurize fruit and vegetable Juices in a short operating time and that the effect of inactivation depends on applied electric field strengths, treatment time and electric conductivity.
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inactivation of escherichia coli o157 h7 salmonella typhimurium and listeria monocytogenes in orange and Tomato Juice using ohmic heating
Journal of Food Protection, 2011Co-Authors: Hungu Sagong, S Ryu, Sanghyun Park, Young Jin Choi, Donghyun KangAbstract:The effects of ohmic heating on reduction of Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes in orange and Tomato Juice were investigated. Orange and Tomato Juice inoculated with E. coli O157:H7, Salmonella Typhimurium, and L. monocytogenes were subjected to ohmic heating with selected parameters including electric field strength from 10 to 20 V/cm and treatment times from 0 to 540 s. The number of pathogens was reduced by increasing the electric field strength from 10 to 20 V/cm as well as increasing treatment time. The population of E. coli O157:H7 was reduced more than 5 log after 120, 210, and 540 s of treatment in orange Juice with 20, 15, and 10 V/cm electric field strengths, respectively. In Tomato Juice, levels of E. coli O157:H7 were reduced more than 5 log after 90, 180, and 480 s with the same electric field strengths. Similar phenomena were observed for Salmonella Typhimurium and L. monocytogenes, but E. coli O157:H7 was the most resistant to ohmic heating treatment. These results show that ohmic heating is potentially useful for inactivation of E. coli O157:H7, Salmonella Typhimurium, and L. monocytogenes and that the effect of inactivation depends on applied electric field strength, treatment time, pathogen species, and type of Juice.
Olga Martinbelloso - One of the best experts on this subject based on the ideXlab platform.
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changes of health related compounds throughout cold storage of Tomato Juice stabilized by thermal or high intensity pulsed electric field treatments
Innovative Food Science and Emerging Technologies, 2008Co-Authors: Isabel Odriozolaserrano, Robert Solivafortuny, Olga MartinbellosoAbstract:Abstract The effect of high intensity pulsed electric fields (HIPEF) processing (35 kV/cm for 1500 μs in bipolar 4-μs pulses at 100 Hz, with an energy density of 8269 kJ/L) on the main bioactive compounds and antioxidant capacity of Tomato Juice was investigated and compared to heat pasteurization (90 °C for 1 min or 30 s) having the fresh Juice as a reference. HIPEF and heat treated Tomato Juices showed higher lycopene and lower vitamin C levels than the untreated Juice. However, no significant changes in the total phenolic content and antioxidant capacity were observed between treated and fresh Juices just after processing. Lycopene, vitamin C and antioxidant capacity of both treated and untreated Juices decreased exponentially during storage following a first order kinetics ( R 2 = 0.763–0.987), whereas Tomato Juices maintained their initial phenolic content. HIPEF-treated Tomato Juice maintained higher lycopene and vitamin C content than the thermally treated Juices during the storage time. Hence, the application of HIPEF may be appropriate to achieve nutritious and fresh like Tomato Juice. Industrial relevance HIPEF processing can lead to Tomato Juice with higher nutritional value than that thermally processed. HIPEF-treated (35 kV/cm for 1500 μs with 4-μs bipolar pulses at 100 Hz, energy input of 8269 kJ/L) Tomato Juice shows greater lycopene, vitamin C and antioxidant capacity just after the treatment and during the storage time than heat treated (90 °C30 s and 90 °C60 s) Tomato Juice. Therefore, HIPEF technology is a feasible alternative to thermal treatment to obtain Tomato Juice with a high presence of health-related compounds.
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comparative study on color viscosity and related enzymes of Tomato Juice treated by high intensity pulsed electric fields or heat
European Food Research and Technology, 2008Co-Authors: Ingrid Aguiloaguayo, Robert Solivafortuny, Olga MartinbellosoAbstract:The effects of high intensity pulsed electric fields (HIPEF) processing (35 kV/cm for 1,500 μs using bipolar 4-μs pulses at 100 Hz) on color parameters and viscosity, as well as peroxidase (POD), pectin methylesterase (PME) and polygalacturonase (PG), were evaluated during 77 days of storage at 4 °C and compared to thermal treatments at 90 °C for 1 min or 30 s for unprocessed Tomato Juice. HIPEF-treated Tomato Juice showed higher values of lightness than the thermally processed and the untreated Juice throughout storage time (P < 0.05). Viscosity of HIPEF-treated Tomato Juice was also greater than both thermally treated and untreated for the first 35 days of storage. POD of HIPEF-treated Tomato Juice was inactivated by 97% whereas in the case of the thermally treated, 90 and 79% inactivation was achieved after 1 min and 30 s, respectively. The highest PME inactivation in Tomato Juice was obtained by PEF (82%) and heat treatment at 90 °C for 1 min (96%). PG of PEF-treated Tomato Juice was inactivated by 12% whereas thermal treatments at 90 °C for 1 min or 30 s achieved 44 and 22%, respectively. Despite the low rates of PG inactivation obtained, the pattern followed in the residual activity along the storage time was similar in the Tomato Juice treated by HIPEF than the thermally processed.
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lycopene vitamin c and antioxidant capacity of Tomato Juice as affected by high intensity pulsed electric fields critical parameters
Journal of Agricultural and Food Chemistry, 2007Co-Authors: Isabel Odriozolaserrano, Ingrid Aguiloaguayo, Robert Solivafortuny, Vicente Gimenoano, Olga MartinbellosoAbstract:The effects of high-intensity pulsed electric field (HIPEF) treatment variables (frequency, pulse width, and pulse polarity) on the lycopene, vitamin C, and antioxidant capacities of Tomato Juice were evaluated using a response surface methodology. An optimization of the HIPEF treatment conditions was carried out to obtain Tomato Juice with the highest content of bioactive compounds possible. Samples were subjected to an electric field intensity set at 35 kV/cm for 1000 µs using squared wave pulses, frequencies from 50 to 250 Hz, and a pulse width from 1 to 7 µs, in monopolar or bipolar mode. Data significantly fit (P < 0.001) the proposed second-order response functions. Pulse frequency, width, and polarity significantly affected the lycopene, vitamin C, and antioxidant capacities of HIPEF-treated Tomato Juice. Maximal relative lycopene content (131.8%), vitamin C content (90.2%), and antioxidant capacity retention (89.4%) were attained with HIPEF treatments of a 1 µs pulse duration applied at 250 Hz in ...
Q H Zhang - One of the best experts on this subject based on the ideXlab platform.
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inactivation kinetics of Tomato Juice lipoxygenase by pulsed electric fields
Journal of Food Science, 2003Co-Authors: Sea C Min, S K Min, Q H ZhangAbstract:ABSTRACT: Pulsed electric field (PEF) inactivation models for Tomato Juice lipoxygenase (LOX) were studied. Tomato Juice was treated by PEF with the combinations of electric field strength (0, 10, 15, 20, 30, 35 kV/cm), PEF treatment time (20, 30, 50, 60, 70 μs), and PEF treatment temperature (10, 20, 30, 40, 50 °C). The first-order inactivation models, Hulsheger's model, Fermi's model, and the 2nd-order polynomial equation adequately described the LOX inactivation. Calculated D values were 161.0, 112.9, 101.0, and 74.8 μs at 15, 20, 30, and 35 kV/cm, respectively, at 30 °C. The activation energy for the inactivation of LOX by PEF was 35.7 kJ/mol. Applied electric field strength was the primary variable for the inactivation of LOX.
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effects of commercial scale pulsed electric field processing on flavor and color of Tomato Juice
Journal of Food Science, 2003Co-Authors: Sea C Min, Q H ZhangAbstract:Effects of commercial-scale pulsed electric field (PEF) processing on the flavor and color of Tomato Juice during storage at 4 deg;for 112 d were studied. Tomato Juice was prepared by hot break at 88°C for 2 min and then thermally processed at 92° for 90 s or PEF processed at 40 kV/cm for 57 μs. The PEF-processed Tomato Juice retained more flavor compounds of trans-2-hexenal, 2-isobutylthiazole, cis-3-hexanol than thermally processed or unprocessed control Tomato Juice (P < 0.05). PEF-processed Juice had significantly lower nonenzymatic browning and higher redness than thermally processed or control Juice (P < 0.05). Sensory evaluations indicated that the flavor of PEF-processed Juice was preferred to that of thermally processed Juice (P < 0.01).
Hungu Sagong - One of the best experts on this subject based on the ideXlab platform.
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effect of continuous ohmic heating to inactivate escherichia coli o157 h7 salmonella typhimurium and listeria monocytogenes in orange Juice and Tomato Juice
Journal of Applied Microbiology, 2012Co-Authors: S Y Lee, Hungu Sagong, S Ryu, Donghyun KangAbstract:Aims: The purpose of this study was to investigate the efficacy of continuous ohmic heating for reducing Escherichia coli O157:H7, Salmonella Typhimurium and Listeria monocytogenes in orange Juice and Tomato Juice. Methods and Results: Orange Juice and Tomato Juice were treated with electric field strengths in the range of 25–40 V cm−1 for different treatment times. The temperature of the samples increased with increasing treatment time and electric field strength. The rate of temperature change for Tomato Juice was higher than for orange Juice at all voltage gradients applied. Higher electric field strength or longer treatment time resulted in a greater reduction of pathogens. Escherichia coli O157:H7 was reduced by more than 5 log after 60-, 90- and 180-s treatments in orange Juice with 40, 35 and 30 V cm−1 electric field strength, respectively. In Tomato Juice, treatment with 25 V cm−1 for 30 s was sufficient to achieve a 5-log reduction in E. coli O157:H7. Similar results were observed in Salm. Typhimurium and L. monocytogenes. The concentration of vitamin C in continuous ohmic heated Juice was significantly higher than in conventionally heated Juice (P < 0·05). Conclusions: Continuous ohmic heating can be effective in killing foodborne pathogens on orange Juice and Tomato Juice with lower degradation of quality than conventional heating. Significance and Impact of the Study: These results suggest that continuous ohmic heating might be effectively used to pasteurize fruit and vegetable Juices in a short operating time and that the effect of inactivation depends on applied electric field strengths, treatment time and electric conductivity.
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inactivation of escherichia coli o157 h7 salmonella typhimurium and listeria monocytogenes in orange and Tomato Juice using ohmic heating
Journal of Food Protection, 2011Co-Authors: Hungu Sagong, S Ryu, Sanghyun Park, Young Jin Choi, Donghyun KangAbstract:The effects of ohmic heating on reduction of Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes in orange and Tomato Juice were investigated. Orange and Tomato Juice inoculated with E. coli O157:H7, Salmonella Typhimurium, and L. monocytogenes were subjected to ohmic heating with selected parameters including electric field strength from 10 to 20 V/cm and treatment times from 0 to 540 s. The number of pathogens was reduced by increasing the electric field strength from 10 to 20 V/cm as well as increasing treatment time. The population of E. coli O157:H7 was reduced more than 5 log after 120, 210, and 540 s of treatment in orange Juice with 20, 15, and 10 V/cm electric field strengths, respectively. In Tomato Juice, levels of E. coli O157:H7 were reduced more than 5 log after 90, 180, and 480 s with the same electric field strengths. Similar phenomena were observed for Salmonella Typhimurium and L. monocytogenes, but E. coli O157:H7 was the most resistant to ohmic heating treatment. These results show that ohmic heating is potentially useful for inactivation of E. coli O157:H7, Salmonella Typhimurium, and L. monocytogenes and that the effect of inactivation depends on applied electric field strength, treatment time, pathogen species, and type of Juice.
Sanghyun Park - One of the best experts on this subject based on the ideXlab platform.
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synergistic effect of ohmic heating and uv c irradiation for inactivation of escherichia coli o157 h7 salmonella typhimurium and listeria monocytogenes in buffered peptone water and Tomato Juice
Food Control, 2019Co-Authors: Sangsoon Kim, Sanghyun Park, Soohwan Kim, Donghyun KangAbstract:Abstract Hurdle technology, in which preservation techniques are combined, has been of interest to scientists aiming to ensure microbiological food safety. We investigated the synergistic effect of UV-C irradiation and ohmic heating on the inactivation of foodborne pathogens. UV-C irradiation and ohmic heating were applied to buffered peptone water and Tomato Juice inoculated with pathogens simultaneously or sequentially. A synergistic bactericidal effect of the simultaneous treatment was observed against Escherichia coli O157:H7, Salmonella Typhimurium and Listeria monocytogenes. For example, the reductions (log CFU/ml) in E. coli O157:H7 by UV-C irradiation, ohmic heating and simultaneous treatment in Tomato Juice were 0.48, 1.84 and 3.83, respectively. Additive effect was observed for cell membrane damage and lipid oxidation values with the simultaneous treatment Therefore, the proposed synergistic bactericidal mechanism by the simultaneous treatment consists of an acceleration of lipid oxidation, which results in an additive effect on cell membrane pore formation. Sequential treatment of UV-C irradiation after ohmic heating showed the least antibacterial effect in buffered peptone water. On the other hand, the reductions levels of all three pathogens in Tomato Juice were not significantly different between the two treatments regardless of the sequence. The color and lycopene content of Tomato Juice were not significantly deteriorated by either ohmic heating or the simultaneous treatment. Therefore, the combination treatment of UV-C irradiation and ohmic heating including simultaneous and sequential treatments, and regardless of treatment sequence, can be used as an effective hurdle technology ensuring microbiological safety in Juice products.
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application of continuous type pulsed ohmic heating system for inactivation of foodborne pathogens in buffered peptone water and Tomato Juice
Lwt - Food Science and Technology, 2018Co-Authors: Sangsoon Kim, Sanghyun Park, Donghyun KangAbstract:Abstract The purpose of this study was to inactivate Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes by continuous-type pulsed ohmic heating in buffered peptone water (BPW) and Tomato Juice. First, BPW inoculated with the three pathogens were treated at different flow rates (0.2–0.4 LPM) and treatment voltages (9.43–12.14 Vrms/cm). Both heating rate of BPW and reduction rates of pathogens increased corresponding to decreased flow rate. Accordingly, higher numbers of pathogens survived at a higher flow rate (0.4 LPM). Increasing treatment voltage was an effective way to inactivate pathogens at 0.4 LPM, but the heating rate overly accelerated with increasing voltage adversely affecting food quality. Alternatively, increasing initial temperature by preheating can help inactivate pathogens in the early treatment stage without affecting heating rate. From the BPW experiments, we identified that treatment conditions such as flow rate, voltage, and initial temperature are important factors determining pathogen inactivation performance of continuous-type ohmic heating. When applied to Tomato Juice, 5 log reductions of all three pathogens were achieved by applying 12.14Vrms/cm ohmic heating with 0.2 LPM flow rate after preheating sample to 50 °C with a water bath. Quality aspects of color and lycopene content were observed, and a∗ and b∗ values decreased after treatment. Because preheating with additional equipment is inconvenient and occupies valuable space, we developed sequential three cylinder type ohmic heating. By applying the developed sequential ohmic heating, 5 log reductions were achieved for all three pathogens without preheating under the same treatment conditions. Therefore, we concluded that sequential continuous-type ohmic heating can be used utizied effectively to control foodborne pathogens by the Juice industry.
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inactivation of escherichia coli o157 h7 salmonella typhimurium and listeria monocytogenes in orange and Tomato Juice using ohmic heating
Journal of Food Protection, 2011Co-Authors: Hungu Sagong, S Ryu, Sanghyun Park, Young Jin Choi, Donghyun KangAbstract:The effects of ohmic heating on reduction of Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes in orange and Tomato Juice were investigated. Orange and Tomato Juice inoculated with E. coli O157:H7, Salmonella Typhimurium, and L. monocytogenes were subjected to ohmic heating with selected parameters including electric field strength from 10 to 20 V/cm and treatment times from 0 to 540 s. The number of pathogens was reduced by increasing the electric field strength from 10 to 20 V/cm as well as increasing treatment time. The population of E. coli O157:H7 was reduced more than 5 log after 120, 210, and 540 s of treatment in orange Juice with 20, 15, and 10 V/cm electric field strengths, respectively. In Tomato Juice, levels of E. coli O157:H7 were reduced more than 5 log after 90, 180, and 480 s with the same electric field strengths. Similar phenomena were observed for Salmonella Typhimurium and L. monocytogenes, but E. coli O157:H7 was the most resistant to ohmic heating treatment. These results show that ohmic heating is potentially useful for inactivation of E. coli O157:H7, Salmonella Typhimurium, and L. monocytogenes and that the effect of inactivation depends on applied electric field strength, treatment time, pathogen species, and type of Juice.