{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/24760"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/24760","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Use of High Pressure Processing to Reduce Foodborne Pathogens in Coconut Water","abstract":"Juices have been implicated in numerous foodborne outbreaks over the last couple of decades. The FDA requires a 5-log10 reduction in juice products, which is most commonly achieved through pasteurization. However, pasteurization deteriorates some sensorial properties and nutritive value. Coconut water (CW; classified as a juice), is rapidly gaining popularity increasing over 300% since 2005. CW has not been implicated in a microbial outbreak, but is thermally processed to achieve the required 5-log10 CFU/ml reduction, which results in negative organoleptic properties. The objectives of this study are to determine whether E. coli O157:H7, Salmonella enterica serovar Typhimurium, and Listeria monocytogenes can grow in CW, and evaluate the use of High Pressure Processing (HPP) to reduce populations of these bacteria in CW. The three pathogens were inoculated separately into CW and bacterial populations were enumerated over 24 hours. All three bacteria reached at least 8-log10 CFU/ml after 24 hours, which was not significantly different from the control (TSB). CW was then inoculated with each pathogen and processed using HPP (400, 5000, or 600 MPa) for 120 seconds. The D-glucose, D-fructose, sucrose, and phenol oxidase levels in the CW were assessed before and after treatments. Following processing, the pathogens were enumerated from the CW. All three pathogens were reduced by more than 6-log10 CFU/ml following treatments of 500 and 600 MPa, enough to achieve the mandatory 5-log CFu/m reduction. There were no significant changes in the D-glucose, D-fructose, sucrose, and phenol oxidase activity after any of the treatments.","abstract_html":"Juices have been implicated in numerous foodborne outbreaks over the last couple of decades. The FDA requires a 5-log10 reduction in juice products, which is most commonly achieved through pasteurization. However, pasteurization deteriorates some sensorial properties and nutritive value. Coconut water (CW; classified as a juice), is rapidly gaining popularity increasing over 300% since 2005. CW has not been implicated in a microbial outbreak, but is thermally processed to achieve the required 5-log10 CFU/ml reduction, which results in negative organoleptic properties. The objectives of this study are to determine whether E. coli O157:H7, Salmonella enterica serovar Typhimurium, and Listeria monocytogenes can grow in CW, and evaluate the use of High Pressure Processing (HPP) to reduce populations of these bacteria in CW. The three pathogens were inoculated separately into CW and bacterial populations were enumerated over 24 hours. All three bacteria reached at least 8-log10 CFU/ml after 24 hours, which was not significantly different from the control (TSB). CW was then inoculated with each pathogen and processed using HPP (400, 5000, or 600 MPa) for 120 seconds. The D-glucose, D-fructose, sucrose, and phenol oxidase levels in the CW were assessed before and after treatments. Following processing, the pathogens were enumerated from the CW. All three pathogens were reduced by more than 6-log10 CFU/ml following treatments of 500 and 600 MPa, enough to achieve the mandatory 5-log CFu/m reduction. There were no significant changes in the D-glucose, D-fructose, sucrose, and phenol oxidase activity after any of the treatments.","abstract_has_math":false,"creators":["Lukas, Anthony R."],"institution":"Virginia Tech","degree_name":"Master of Science in Life Sciences","degree_level":"masters","degree_discipline":"Food Science and Technology","degree_department":"Food Science and Technology","school":null,"contributors":[],"advisors":[],"committee_chairs":["Boyer, Renee R."],"committee_members":["O'Keefe, Sean F.","Williams, Robert C."],"year":2013,"date_issued":"2013-12-18","date_published":"2013-12-18","updated_at":"2026-07-22T22:19:31Z","subjects":["E. coli","Salmonella","Listeria","Coconut Water","High Pressure Processing"],"languages":[],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["vt_gsexam:2016"],"render_values":[{"text":"vt_gsexam:2016","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10919/24760","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.committeechair","label":"Committee Chair","values":["Boyer, Renee R."]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["O'Keefe, Sean F.","Williams, Robert C."]},{"key":"dc:contributor.department","label":"Department","values":["Food Science and Technology"]},{"key":"dc:creator","label":"Author","values":["Lukas, Anthony R."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2013-12-19T09:00:10Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2013-12-19T09:00:10Z"]},{"key":"dc:date.issued","label":"Date","values":["2013-12-18"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Food Science and Technology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science in Life Sciences"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["E. coli","Salmonella","Listeria","Coconut Water","High Pressure Processing"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["vt_gsexam:2016"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/24760"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Juices have been implicated in numerous foodborne outbreaks over the last couple of decades. The FDA requires a 5-log10 reduction in juice products, which is most commonly achieved through pasteurization. However, pasteurization deteriorates some sensorial properties and nutritive value. Coconut water (CW; classified as a juice), is rapidly gaining popularity increasing over 300% since 2005. CW has not been implicated in a microbial outbreak, but is thermally processed to achieve the required 5-log10 CFU/ml reduction, which results in negative organoleptic properties. The objectives of this study are to determine whether E. coli O157:H7, Salmonella enterica serovar Typhimurium, and Listeria monocytogenes can grow in CW, and evaluate the use of High Pressure Processing (HPP) to reduce populations of these bacteria in CW. The three pathogens were inoculated separately into CW and bacterial populations were enumerated over 24 hours. All three bacteria reached at least 8-log10 CFU/ml after 24 hours, which was not significantly different from the control (TSB). CW was then inoculated with each pathogen and processed using HPP (400, 5000, or 600 MPa) for 120 seconds. The D-glucose, D-fructose, sucrose, and phenol oxidase levels in the CW were assessed before and after treatments. Following processing, the pathogens were enumerated from the CW. All three pathogens were reduced by more than 6-log10 CFU/ml following treatments of 500 and 600 MPa, enough to achieve the mandatory 5-log CFu/m reduction. There were no significant changes in the D-glucose, D-fructose, sucrose, and phenol oxidase activity after any of the treatments."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science in Life Sciences"]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["ETD"]},{"key":"dc:title","label":"Title","values":["Use of High Pressure Processing to Reduce Foodborne Pathogens in Coconut Water"]}]}],"canonical_facts":{"dc:contributor.committeechair":["Boyer, Renee R."],"dc:contributor.committeemember":["O'Keefe, Sean F.","Williams, Robert C."],"dc:contributor.department":["Food Science and Technology"],"dc:creator":["Lukas, Anthony R."],"dc:date.accessioned":["2013-12-19T09:00:10Z"],"dc:date.available":["2013-12-19T09:00:10Z"],"dc:date.issued":["2013-12-18"],"dc:description.abstract":["Juices have been implicated in numerous foodborne outbreaks over the last couple of decades. The FDA requires a 5-log10 reduction in juice products, which is most commonly achieved through pasteurization. However, pasteurization deteriorates some sensorial properties and nutritive value. Coconut water (CW; classified as a juice), is rapidly gaining popularity increasing over 300% since 2005. CW has not been implicated in a microbial outbreak, but is thermally processed to achieve the required 5-log10 CFU/ml reduction, which results in negative organoleptic properties. The objectives of this study are to determine whether E. coli O157:H7, Salmonella enterica serovar Typhimurium, and Listeria monocytogenes can grow in CW, and evaluate the use of High Pressure Processing (HPP) to reduce populations of these bacteria in CW. The three pathogens were inoculated separately into CW and bacterial populations were enumerated over 24 hours. All three bacteria reached at least 8-log10 CFU/ml after 24 hours, which was not significantly different from the control (TSB). CW was then inoculated with each pathogen and processed using HPP (400, 5000, or 600 MPa) for 120 seconds. The D-glucose, D-fructose, sucrose, and phenol oxidase levels in the CW were assessed before and after treatments. Following processing, the pathogens were enumerated from the CW. All three pathogens were reduced by more than 6-log10 CFU/ml following treatments of 500 and 600 MPa, enough to achieve the mandatory 5-log CFu/m reduction. There were no significant changes in the D-glucose, D-fructose, sucrose, and phenol oxidase activity after any of the treatments."],"dc:description.degree":["Master of Science in Life Sciences"],"dc:format.medium":["ETD"],"dc:identifier.other":["vt_gsexam:2016"],"dc:identifier.uri":["http://hdl.handle.net/10919/24760"],"dc:publisher":["Virginia Tech"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:subject":["E. coli","Salmonella","Listeria","Coconut Water","High Pressure Processing"],"dc:title":["Use of High Pressure Processing to Reduce Foodborne Pathogens in Coconut Water"],"dc:type":["Thesis"],"thesis:degree_discipline":["Food Science and Technology"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science in Life Sciences"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:19:31Z"}