The Experts below are selected from a list of 2154 Experts worldwide ranked by ideXlab platform
David J. Geveke - One of the best experts on this subject based on the ideXlab platform.
-
nonthermal inactivation and sublethal injury of lactobacillus plantarum in Apple Cider by a pilot plant scale continuous supercritical carbon dioxide system
Food Microbiology, 2011Co-Authors: Hyungyun Yuk, David J. GevekeAbstract:The objective of this study was to evaluate the efficacy of supercritical carbon dioxide (SCCO(2)) for inactivating Lactobacillus plantarum in Apple Cider using a continuous system with a gas-liquid metal contactor. Pasteurized Apple Cider without preservatives was inoculated with L. plantarum and processed using a SCCO(2) system at a CO(2) concentration range of 0-12% (g CO(2)/100g product), outlet temperatures of 34, 38, and 42 °C, a system pressure of 7.6 MPa, and a flow rate of 1 L/min. Processing with SCCO(2) significantly (P<0.05) enhanced inactivation of L. plantarum in Apple Cider, resulting in a 5 log reduction with 8% CO(2) at 42 °C. The response surface model indicated that both CO(2) concentration and temperature contributed to the microbial inactivation. The extent of sublethal injury in surviving cells in processed Apple Cider increased as CO(2) concentration and processing temperature increased, however the percent injury dramatically decreased during SCCO(2) processing at 42 °C. Structural damage in cell membranes after SCCO(2) processing was observed by SEM. Refrigeration (4 °C) after SCCO(2) processing effectively inhibited the re-growth of surviving L. plantarum during storage for 28 days. Thus this study suggests that SCCO(2) processing is effective in eliminating L. plantarum and could be applicable for nonthermal pasteurization of Apple Cider.
-
Nonthermal inactivation and sublethal injury of Lactobacillus plantarum in Apple Cider by a pilot plant scale continuous supercritical carbon dioxide system
Food Microbiology, 2011Co-Authors: Hyungyun Yuk, David J. GevekeAbstract:Abstract The objective of this study was to evaluate the efficacy of supercritical carbon dioxide (SCCO 2 ) for inactivating Lactobacillus plantarum in Apple Cider using a continuous system with a gas-liquid metal contactor. Pasteurized Apple Cider without preservatives was inoculated with L. plantarum and processed using a SCCO 2 system at a CO 2 concentration range of 0–12% (g CO 2 /100 g product), outlet temperatures of 34, 38, and 42 °C, a system pressure of 7.6 MPa, and a flow rate of 1 L/min. Processing with SCCO 2 significantly ( P L. plantarum in Apple Cider, resulting in a 5 log reduction with 8% CO 2 at 42 °C. The response surface model indicated that both CO 2 concentration and temperature contributed to the microbial inactivation. The extent of sublethal injury in surviving cells in processed Apple Cider increased as CO 2 concentration and processing temperature increased, however the percent injury dramatically decreased during SCCO 2 processing at 42 °C. Structural damage in cell membranes after SCCO 2 processing was observed by SEM. Refrigeration (4 °C) after SCCO 2 processing effectively inhibited the re-growth of surviving L. plantarum during storage for 28 days. Thus this study suggests that SCCO 2 processing is effective in eliminating L. plantarum and could be applicable for nonthermal pasteurization of Apple Cider.
-
Thermal and nonthermal processing of Apple Cider: storage quality under equivalent process conditions
Journal of Food Quality, 2010Co-Authors: Zareena Azhuvalappil, David J. Geveke, Xuetong Fan, Howard Q ZhangAbstract:ABSTRACT Three processing techniques: heat, pulsed electric field (PEF) and ultraviolet (UV) light were optimized to achieve a similar 6 log reduction of inoculated Escherichia coli K12 in Apple Cider. Microbial populations (total aerobic and yeast and mold), sensory, color and physical properties (pH and°Brix) of processed Apple Cider were investigated during 4-week storage at 4C. PEF and thermally processed Cider maintained good microbial quality during 4 weeks of storage while UV-treated Cider showed a significant (P
-
thermal and nonthermal processing of Apple Cider storage quality under equivalent process conditions
Journal of Food Quality, 2010Co-Authors: Zareena Azhuvalappil, David J. Geveke, Xuetong Fan, Howard Q ZhangAbstract:ABSTRACT Three processing techniques: heat, pulsed electric field (PEF) and ultraviolet (UV) light were optimized to achieve a similar 6 log reduction of inoculated Escherichia coli K12 in Apple Cider. Microbial populations (total aerobic and yeast and mold), sensory, color and physical properties (pH and°Brix) of processed Apple Cider were investigated during 4-week storage at 4C. PEF and thermally processed Cider maintained good microbial quality during 4 weeks of storage while UV-treated Cider showed a significant (P < 0.05) growth in yeast and mold after 2 weeks of storage. As a result,°Brix value decreased significantly (P < 0.05) for UV Cider after 4 weeks of storage. Apple Cider pH was neither affected by any treatment nor by storage. Thermal and UV-pasteurized Ciders faded significantly (P < 0.05) during storage (International Commission on Illumination L*[lightness] and b*[yellow] values increased) compared to PEF Cider. Triangle sensory analysis indicated a significant difference (P < 0.05) in aroma between treatments. PEF-treated Cider was preferred over thermal and UV Cider by sensory panelists at the end of the storage period. The results suggested that PEF-treated Apple Cider had a longer shelf life than UV-treated Cider and a better aroma and color than thermally processed sample. PRACTICAL APPLICATIONS Nonthermal processes like pulsed electric field (PEF) and ultraviolet (UV) light are developed as alternative pasteurization technologies to heat for their efficacy to extend shelf life and enhance the safety of fresh juice while preserving organoleptic and nutritional qualities. For fair comparison of the effects on quality of juice, both thermal and nonthermal processes must achieve equivalent reduction in microorganism levels. In the present study, the effect of PEF, UV and thermal techniques on Apple Cider quality are compared at conditions optimized to achieve equivalent 6 log reductions in Escherichia coli. Our results showed that PEF extended the shelf-life of Apple Cider by inactivating spoilage microorganisms compared to UV processing, and better preserved the freshness (aroma and color) over traditional thermal processing. Based on these results, PEF process is the best choice among the three technologies studied.
-
efficacy of supercritical carbon dioxide for nonthermal inactivation of escherichia coli k12 in Apple Cider
International Journal of Food Microbiology, 2010Co-Authors: Hyungyun Yuk, David J. Geveke, Howard Q ZhangAbstract:This study evaluated the efficacy of a supercritical carbon dioxide (SCCO(2)) system with a gas-liquid porous metal contactor for eliminating Escherichia coli K12 in Apple Cider. Pasteurized, preservative-free Apple Cider was inoculated with E. coli K12 and processed using the SCCO(2) system at CO(2) concentrations of 0-10% (wt.%, g CO(2)/100g product), outlet temperatures of 34, 38, and 42 degrees C, a system pressure of 7.6 MPa, and a flow rate of 1L/min. Increased CO(2) concentrations and temperatures significantly (P<0.05) enhanced the bactericidal effect, resulting in a maximum reduction of 7.31 log CFU/mL at 8% CO(2) and 42 degrees C. A response surface model indicated that minimum CO(2) concentrations of 9.9% at 34 degrees C, 7.4% at 38 degrees C, and 5.4% at 42 degrees C are needed to achieve a 5-log reduction of E. coli K12 in Apple Cider. SEM observations showed morphological changes in the cell envelope after SCCO(2) processing. At a processing condition of 8% and 38 degrees C, the reduction of E. coli was 6.03 log and the sublethal injury of the survivors was 84%. The regrowth or survival of E. coli in SCCO(2) processed Apple Cider was not observed during storage for 28 days at 4, 8, and 20 degrees C. Thus this study showed the potential of SCCO(2) processing with a gas-liquid porous metal contactor for the nonthermal pasteurization of Apple Cider.
Howard Q Zhang - One of the best experts on this subject based on the ideXlab platform.
-
Thermal and nonthermal processing of Apple Cider: storage quality under equivalent process conditions
Journal of Food Quality, 2010Co-Authors: Zareena Azhuvalappil, David J. Geveke, Xuetong Fan, Howard Q ZhangAbstract:ABSTRACT Three processing techniques: heat, pulsed electric field (PEF) and ultraviolet (UV) light were optimized to achieve a similar 6 log reduction of inoculated Escherichia coli K12 in Apple Cider. Microbial populations (total aerobic and yeast and mold), sensory, color and physical properties (pH and°Brix) of processed Apple Cider were investigated during 4-week storage at 4C. PEF and thermally processed Cider maintained good microbial quality during 4 weeks of storage while UV-treated Cider showed a significant (P
-
thermal and nonthermal processing of Apple Cider storage quality under equivalent process conditions
Journal of Food Quality, 2010Co-Authors: Zareena Azhuvalappil, David J. Geveke, Xuetong Fan, Howard Q ZhangAbstract:ABSTRACT Three processing techniques: heat, pulsed electric field (PEF) and ultraviolet (UV) light were optimized to achieve a similar 6 log reduction of inoculated Escherichia coli K12 in Apple Cider. Microbial populations (total aerobic and yeast and mold), sensory, color and physical properties (pH and°Brix) of processed Apple Cider were investigated during 4-week storage at 4C. PEF and thermally processed Cider maintained good microbial quality during 4 weeks of storage while UV-treated Cider showed a significant (P < 0.05) growth in yeast and mold after 2 weeks of storage. As a result,°Brix value decreased significantly (P < 0.05) for UV Cider after 4 weeks of storage. Apple Cider pH was neither affected by any treatment nor by storage. Thermal and UV-pasteurized Ciders faded significantly (P < 0.05) during storage (International Commission on Illumination L*[lightness] and b*[yellow] values increased) compared to PEF Cider. Triangle sensory analysis indicated a significant difference (P < 0.05) in aroma between treatments. PEF-treated Cider was preferred over thermal and UV Cider by sensory panelists at the end of the storage period. The results suggested that PEF-treated Apple Cider had a longer shelf life than UV-treated Cider and a better aroma and color than thermally processed sample. PRACTICAL APPLICATIONS Nonthermal processes like pulsed electric field (PEF) and ultraviolet (UV) light are developed as alternative pasteurization technologies to heat for their efficacy to extend shelf life and enhance the safety of fresh juice while preserving organoleptic and nutritional qualities. For fair comparison of the effects on quality of juice, both thermal and nonthermal processes must achieve equivalent reduction in microorganism levels. In the present study, the effect of PEF, UV and thermal techniques on Apple Cider quality are compared at conditions optimized to achieve equivalent 6 log reductions in Escherichia coli. Our results showed that PEF extended the shelf-life of Apple Cider by inactivating spoilage microorganisms compared to UV processing, and better preserved the freshness (aroma and color) over traditional thermal processing. Based on these results, PEF process is the best choice among the three technologies studied.
-
efficacy of supercritical carbon dioxide for nonthermal inactivation of escherichia coli k12 in Apple Cider
International Journal of Food Microbiology, 2010Co-Authors: Hyungyun Yuk, David J. Geveke, Howard Q ZhangAbstract:This study evaluated the efficacy of a supercritical carbon dioxide (SCCO(2)) system with a gas-liquid porous metal contactor for eliminating Escherichia coli K12 in Apple Cider. Pasteurized, preservative-free Apple Cider was inoculated with E. coli K12 and processed using the SCCO(2) system at CO(2) concentrations of 0-10% (wt.%, g CO(2)/100g product), outlet temperatures of 34, 38, and 42 degrees C, a system pressure of 7.6 MPa, and a flow rate of 1L/min. Increased CO(2) concentrations and temperatures significantly (P<0.05) enhanced the bactericidal effect, resulting in a maximum reduction of 7.31 log CFU/mL at 8% CO(2) and 42 degrees C. A response surface model indicated that minimum CO(2) concentrations of 9.9% at 34 degrees C, 7.4% at 38 degrees C, and 5.4% at 42 degrees C are needed to achieve a 5-log reduction of E. coli K12 in Apple Cider. SEM observations showed morphological changes in the cell envelope after SCCO(2) processing. At a processing condition of 8% and 38 degrees C, the reduction of E. coli was 6.03 log and the sublethal injury of the survivors was 84%. The regrowth or survival of E. coli in SCCO(2) processed Apple Cider was not observed during storage for 28 days at 4, 8, and 20 degrees C. Thus this study showed the potential of SCCO(2) processing with a gas-liquid porous metal contactor for the nonthermal pasteurization of Apple Cider.
-
efficacy of supercritical carbon dioxide for nonthermal inactivation of escherichia coli k12 in Apple Cider
International Journal of Food Microbiology, 2010Co-Authors: David J. Geveke, Howard Q ZhangAbstract:Abstract This study evaluated the efficacy of a supercritical carbon dioxide (SCCO2) system with a gas–liquid porous metal contactor for eliminating Escherichia coli K12 in Apple Cider. Pasteurized, preservative-free Apple Cider was inoculated with E. coli K12 and processed using the SCCO2 system at CO2 concentrations of 0–10% (wt.%, g CO2/100 g product), outlet temperatures of 34, 38, and 42 °C, a system pressure of 7.6 MPa, and a flow rate of 1 L/min. Increased CO2 concentrations and temperatures significantly (P
-
Efficacy of supercritical carbon dioxide for nonthermal inactivation of Escherichia coli K12 in Apple Cider.
International Journal of Food Microbiology, 2009Co-Authors: Hyungyun Yuk, David J. Geveke, Howard Q ZhangAbstract:This study evaluated the efficacy of a supercritical carbon dioxide (SCCO(2)) system with a gas-liquid porous metal contactor for eliminating Escherichia coli K12 in Apple Cider. Pasteurized, preservative-free Apple Cider was inoculated with E. coli K12 and processed using the SCCO(2) system at CO(2) concentrations of 0-10% (wt.%, g CO(2)/100g product), outlet temperatures of 34, 38, and 42 degrees C, a system pressure of 7.6 MPa, and a flow rate of 1L/min. Increased CO(2) concentrations and temperatures significantly (P
Hyungyun Yuk - One of the best experts on this subject based on the ideXlab platform.
-
nonthermal inactivation and sublethal injury of lactobacillus plantarum in Apple Cider by a pilot plant scale continuous supercritical carbon dioxide system
Food Microbiology, 2011Co-Authors: Hyungyun Yuk, David J. GevekeAbstract:The objective of this study was to evaluate the efficacy of supercritical carbon dioxide (SCCO(2)) for inactivating Lactobacillus plantarum in Apple Cider using a continuous system with a gas-liquid metal contactor. Pasteurized Apple Cider without preservatives was inoculated with L. plantarum and processed using a SCCO(2) system at a CO(2) concentration range of 0-12% (g CO(2)/100g product), outlet temperatures of 34, 38, and 42 °C, a system pressure of 7.6 MPa, and a flow rate of 1 L/min. Processing with SCCO(2) significantly (P<0.05) enhanced inactivation of L. plantarum in Apple Cider, resulting in a 5 log reduction with 8% CO(2) at 42 °C. The response surface model indicated that both CO(2) concentration and temperature contributed to the microbial inactivation. The extent of sublethal injury in surviving cells in processed Apple Cider increased as CO(2) concentration and processing temperature increased, however the percent injury dramatically decreased during SCCO(2) processing at 42 °C. Structural damage in cell membranes after SCCO(2) processing was observed by SEM. Refrigeration (4 °C) after SCCO(2) processing effectively inhibited the re-growth of surviving L. plantarum during storage for 28 days. Thus this study suggests that SCCO(2) processing is effective in eliminating L. plantarum and could be applicable for nonthermal pasteurization of Apple Cider.
-
Nonthermal inactivation and sublethal injury of Lactobacillus plantarum in Apple Cider by a pilot plant scale continuous supercritical carbon dioxide system
Food Microbiology, 2011Co-Authors: Hyungyun Yuk, David J. GevekeAbstract:Abstract The objective of this study was to evaluate the efficacy of supercritical carbon dioxide (SCCO 2 ) for inactivating Lactobacillus plantarum in Apple Cider using a continuous system with a gas-liquid metal contactor. Pasteurized Apple Cider without preservatives was inoculated with L. plantarum and processed using a SCCO 2 system at a CO 2 concentration range of 0–12% (g CO 2 /100 g product), outlet temperatures of 34, 38, and 42 °C, a system pressure of 7.6 MPa, and a flow rate of 1 L/min. Processing with SCCO 2 significantly ( P L. plantarum in Apple Cider, resulting in a 5 log reduction with 8% CO 2 at 42 °C. The response surface model indicated that both CO 2 concentration and temperature contributed to the microbial inactivation. The extent of sublethal injury in surviving cells in processed Apple Cider increased as CO 2 concentration and processing temperature increased, however the percent injury dramatically decreased during SCCO 2 processing at 42 °C. Structural damage in cell membranes after SCCO 2 processing was observed by SEM. Refrigeration (4 °C) after SCCO 2 processing effectively inhibited the re-growth of surviving L. plantarum during storage for 28 days. Thus this study suggests that SCCO 2 processing is effective in eliminating L. plantarum and could be applicable for nonthermal pasteurization of Apple Cider.
-
efficacy of supercritical carbon dioxide for nonthermal inactivation of escherichia coli k12 in Apple Cider
International Journal of Food Microbiology, 2010Co-Authors: Hyungyun Yuk, David J. Geveke, Howard Q ZhangAbstract:This study evaluated the efficacy of a supercritical carbon dioxide (SCCO(2)) system with a gas-liquid porous metal contactor for eliminating Escherichia coli K12 in Apple Cider. Pasteurized, preservative-free Apple Cider was inoculated with E. coli K12 and processed using the SCCO(2) system at CO(2) concentrations of 0-10% (wt.%, g CO(2)/100g product), outlet temperatures of 34, 38, and 42 degrees C, a system pressure of 7.6 MPa, and a flow rate of 1L/min. Increased CO(2) concentrations and temperatures significantly (P<0.05) enhanced the bactericidal effect, resulting in a maximum reduction of 7.31 log CFU/mL at 8% CO(2) and 42 degrees C. A response surface model indicated that minimum CO(2) concentrations of 9.9% at 34 degrees C, 7.4% at 38 degrees C, and 5.4% at 42 degrees C are needed to achieve a 5-log reduction of E. coli K12 in Apple Cider. SEM observations showed morphological changes in the cell envelope after SCCO(2) processing. At a processing condition of 8% and 38 degrees C, the reduction of E. coli was 6.03 log and the sublethal injury of the survivors was 84%. The regrowth or survival of E. coli in SCCO(2) processed Apple Cider was not observed during storage for 28 days at 4, 8, and 20 degrees C. Thus this study showed the potential of SCCO(2) processing with a gas-liquid porous metal contactor for the nonthermal pasteurization of Apple Cider.
-
Efficacy of supercritical carbon dioxide for nonthermal inactivation of Escherichia coli K12 in Apple Cider.
International Journal of Food Microbiology, 2009Co-Authors: Hyungyun Yuk, David J. Geveke, Howard Q ZhangAbstract:This study evaluated the efficacy of a supercritical carbon dioxide (SCCO(2)) system with a gas-liquid porous metal contactor for eliminating Escherichia coli K12 in Apple Cider. Pasteurized, preservative-free Apple Cider was inoculated with E. coli K12 and processed using the SCCO(2) system at CO(2) concentrations of 0-10% (wt.%, g CO(2)/100g product), outlet temperatures of 34, 38, and 42 degrees C, a system pressure of 7.6 MPa, and a flow rate of 1L/min. Increased CO(2) concentrations and temperatures significantly (P
Randy W Worobo - One of the best experts on this subject based on the ideXlab platform.
-
efficient reduction of pathogenic and spoilage microorganisms from Apple Cider by combining microfiltration with uv treatment
Journal of Food Protection, 2015Co-Authors: Dongjun Zhao, Olga I Padillazakour, Randy W Worobo, John J Churey, Jessie Usaga Barrientos, Qing Wang, Sarah M Markland, Kalmia E Kniel, Carmen I MoraruAbstract:Thermal pasteurization can achieve the U.S. Food and Drug Administration–required 5-log reduction of pathogenic Escherichia coli O157:H7 and Cryptosporidium parvum in Apple juice and Cider, but it can also negatively affect the nutritional and organoleptic properties of the treated products. In addition, thermal pasteurization is only marginally effective against the acidophilic, thermophilic, and spore-forming bacteria Alicyclobacillus spp., which is known to cause off-flavors in juice products. In this study, the efficiency of a combined microfiltration (MF) and UV process as a nonthermal treatment for the reduction of pathogenic and nonpathogenic E. coli, C. parvum, and Alicyclobacillus acidoterrestris from Apple Cider was investigated. MF was used to physically remove suspended solids and microorganisms from Apple Cider, thus enhancing the effectiveness of UV and allowing a lower UV dose to be used. MF, with ceramic membranes (pore sizes, 0.8 and 1.4 μm), was performed at a temperature of 10°C and a t...
-
modeling of escherichia coli inactivation by uv irradiation at different ph values in Apple Cider
Journal of Food Protection, 2004Co-Authors: Armando Quinteroramos, John J Churey, P Hartman, John Barnard, Randy W WoroboAbstract:This study examined the effects and interactions of UV light dose (1,800 to 20,331 μJ/cm2) and Apple Cider pH (2.99 to 4.41) on the inactivation of Escherichia coli ATCC 25922, a surrogate for E. coli O157:H7. A predictive model was developed to relate the log reduction factor of E. coli ATCC 25922 to the UV dose. Bacterial populations for treated and untreated samples were enumerated with the use of nonselective media. The results revealed that UV dose was highly significant in the inactivation of E. coli, whereas pH showed no significant effect at higher UV doses. Doses of 6,500 μJ/cm2 or more were sufficient to achieve a greater than 5-log reduction of E. coli. Experimental inactivation data were fitted adequately by a logistic regression model. UV irradiation is an attractive alternative to conventional methods for reducing bacteria in unpasteurized Apple Cider.
-
inactivation of cryptosporidium parvum oocysts in fresh Apple Cider by uv irradiation
Applied and Environmental Microbiology, 2002Co-Authors: D E Hanes, Randy W Worobo, Palmer A Orlandi, D H Burr, M D Miliotis, M G Robl, J W Bier, Michael J Arrowood, John J Churey, G J JacksonAbstract:This study evaluated the efficacy of UV irradiation on the inactivation of Cryptosporidium parvum oocysts in fresh Apple Cider. Cider was inoculated with oocysts and exposed to 14.32 mJ of UV irradiation/cm2. Oocyst viability was assessed with the gamma interferon gene knockout (GKO) mouse and infant BALB/cByJ mouse models. All GKO mice challenged with UV-treated Cider demonstrated no morbidity or mortality, and infant BALB/c mice challenged with treated Cider were negative for the presence of C. parvum. In contrast, the GKO mice challenged with non-UV-treated inoculated Cider died and the parasite was detected in the ileums of all challenged infant mice. This study shows that UV irradiation can be used to inactivate C. parvum in fresh Apple Cider.
John J Churey - One of the best experts on this subject based on the ideXlab platform.
-
efficient reduction of pathogenic and spoilage microorganisms from Apple Cider by combining microfiltration with uv treatment
Journal of Food Protection, 2015Co-Authors: Dongjun Zhao, Olga I Padillazakour, Randy W Worobo, John J Churey, Jessie Usaga Barrientos, Qing Wang, Sarah M Markland, Kalmia E Kniel, Carmen I MoraruAbstract:Thermal pasteurization can achieve the U.S. Food and Drug Administration–required 5-log reduction of pathogenic Escherichia coli O157:H7 and Cryptosporidium parvum in Apple juice and Cider, but it can also negatively affect the nutritional and organoleptic properties of the treated products. In addition, thermal pasteurization is only marginally effective against the acidophilic, thermophilic, and spore-forming bacteria Alicyclobacillus spp., which is known to cause off-flavors in juice products. In this study, the efficiency of a combined microfiltration (MF) and UV process as a nonthermal treatment for the reduction of pathogenic and nonpathogenic E. coli, C. parvum, and Alicyclobacillus acidoterrestris from Apple Cider was investigated. MF was used to physically remove suspended solids and microorganisms from Apple Cider, thus enhancing the effectiveness of UV and allowing a lower UV dose to be used. MF, with ceramic membranes (pore sizes, 0.8 and 1.4 μm), was performed at a temperature of 10°C and a t...
-
modeling of escherichia coli inactivation by uv irradiation at different ph values in Apple Cider
Journal of Food Protection, 2004Co-Authors: Armando Quinteroramos, John J Churey, P Hartman, John Barnard, Randy W WoroboAbstract:This study examined the effects and interactions of UV light dose (1,800 to 20,331 μJ/cm2) and Apple Cider pH (2.99 to 4.41) on the inactivation of Escherichia coli ATCC 25922, a surrogate for E. coli O157:H7. A predictive model was developed to relate the log reduction factor of E. coli ATCC 25922 to the UV dose. Bacterial populations for treated and untreated samples were enumerated with the use of nonselective media. The results revealed that UV dose was highly significant in the inactivation of E. coli, whereas pH showed no significant effect at higher UV doses. Doses of 6,500 μJ/cm2 or more were sufficient to achieve a greater than 5-log reduction of E. coli. Experimental inactivation data were fitted adequately by a logistic regression model. UV irradiation is an attractive alternative to conventional methods for reducing bacteria in unpasteurized Apple Cider.
-
inactivation of cryptosporidium parvum oocysts in fresh Apple Cider by uv irradiation
Applied and Environmental Microbiology, 2002Co-Authors: D E Hanes, Randy W Worobo, Palmer A Orlandi, D H Burr, M D Miliotis, M G Robl, J W Bier, Michael J Arrowood, John J Churey, G J JacksonAbstract:This study evaluated the efficacy of UV irradiation on the inactivation of Cryptosporidium parvum oocysts in fresh Apple Cider. Cider was inoculated with oocysts and exposed to 14.32 mJ of UV irradiation/cm2. Oocyst viability was assessed with the gamma interferon gene knockout (GKO) mouse and infant BALB/cByJ mouse models. All GKO mice challenged with UV-treated Cider demonstrated no morbidity or mortality, and infant BALB/c mice challenged with treated Cider were negative for the presence of C. parvum. In contrast, the GKO mice challenged with non-UV-treated inoculated Cider died and the parasite was detected in the ileums of all challenged infant mice. This study shows that UV irradiation can be used to inactivate C. parvum in fresh Apple Cider.
