{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/43806"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/43806","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Modified atmosphere packaging of hard grated cheeses","abstract":"The objective of this study was to use MAP technology to produce safe, shelf-stable, high quality, hard grated cheeses not requiring preservatives or refrigeration during distribution and sale. Initially, a challenge study with Staphylococcus aureus (S. aureus) was conducted to determine the water activity (Aw) level of high-moisture cheeses necessary to prevent the growth of a food pathogen when packaged under a modified atmosphere (25% CO, and 75% N,). Other microbial analysis included mold and yeast enumerations. Secondly, product quality and shelf stability were determined biweekly by sensory, microbial, and instrumental analysis to evaluate product safety and changes in the natural aromas and flavors of hard grated cheeses. Instrument color analysis CIE L* a* b* values were determined to measure color changes. Parmesan cheese with high Aw levels (Aw= 0.90 and 0.88) supported the growth and survival of S. aureus. The microorganism was incapable of surviving at Aw levels of 0.86 and below. S. aureus was not able to survive on Romano cheese. Mold and yeast proliferated on higher Aw Parmesan cheeses. Visible mold was detected on the Parmesan sample of Aw= 0.90 after 8 weeks of storage. No mold growth was observed on Romano cheese. However, yeast were capable of growing on Romano cheese. The sensory evaluation study of hard grated cheeses was unable to detect a difference between the fresh cheese sample and the cheeses packaged under MAP.","abstract_html":"The objective of this study was to use MAP technology to produce safe, shelf-stable, high quality, hard grated cheeses not requiring preservatives or refrigeration during distribution and sale. Initially, a challenge study with Staphylococcus aureus (S. aureus) was conducted to determine the water activity (Aw) level of high-moisture cheeses necessary to prevent the growth of a food pathogen when packaged under a modified atmosphere (25% CO, and 75% N,). Other microbial analysis included mold and yeast enumerations. Secondly, product quality and shelf stability were determined biweekly by sensory, microbial, and instrumental analysis to evaluate product safety and changes in the natural aromas and flavors of hard grated cheeses. Instrument color analysis CIE L* a* b* values were determined to measure color changes. Parmesan cheese with high Aw levels (Aw= 0.90 and 0.88) supported the growth and survival of S. aureus. The microorganism was incapable of surviving at Aw levels of 0.86 and below. S. aureus was not able to survive on Romano cheese. Mold and yeast proliferated on higher Aw Parmesan cheeses. Visible mold was detected on the Parmesan sample of Aw= 0.90 after 8 weeks of storage. No mold growth was observed on Romano cheese. However, yeast were capable of growing on Romano cheese. The sensory evaluation study of hard grated cheeses was unable to detect a difference between the fresh cheese sample and the cheeses packaged under MAP.","abstract_has_math":false,"creators":["Yoder, Jonna D."],"institution":"Virginia Tech","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Food Science and Technology","degree_department":"Food Science and Technology","school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1994,"date_issued":"1994","date_published":"1994","updated_at":"2026-07-22T22:19:01Z","subjects":[],"languages":["en"],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-07212009-040516"],"render_values":[{"text":"etd-07212009-040516","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10919/43806","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.department","label":"Department","values":["Food Science and Technology"]},{"key":"dc:creator","label":"Author","values":["Yoder, Jonna D."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-03-14T21:40:48Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-03-14T21:40:48Z","2009-07-21"]},{"key":"dc:date.issued","label":"Date","values":["1994"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.dcmitype","label":"Dc Type Dcmitype","values":["Text"]},{"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"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]},{"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":["etd-07212009-040516"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/43806"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The objective of this study was to use MAP technology to produce safe, shelf-stable, high quality, hard grated cheeses not requiring preservatives or refrigeration during distribution and sale. Initially, a challenge study with Staphylococcus aureus (S. aureus) was conducted to determine the water activity (Aw) level of high-moisture cheeses necessary to prevent the growth of a food pathogen when packaged under a modified atmosphere (25% CO, and 75% N,). Other microbial analysis included mold and yeast enumerations. Secondly, product quality and shelf stability were determined biweekly by sensory, microbial, and instrumental analysis to evaluate product safety and changes in the natural aromas and flavors of hard grated cheeses. Instrument color analysis CIE L* a* b* values were determined to measure color changes. Parmesan cheese with high Aw levels (Aw= 0.90 and 0.88) supported the growth and survival of S. aureus. The microorganism was incapable of surviving at Aw levels of 0.86 and below. S. aureus was not able to survive on Romano cheese. Mold and yeast proliferated on higher Aw Parmesan cheeses. Visible mold was detected on the Parmesan sample of Aw= 0.90 after 8 weeks of storage. No mold growth was observed on Romano cheese. However, yeast were capable of growing on Romano cheese. The sensory evaluation study of hard grated cheeses was unable to detect a difference between the fresh cheese sample and the cheeses packaged under MAP."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["BTD"]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Modified atmosphere packaging of hard grated cheeses"]}]}],"canonical_facts":{"dc:contributor.department":["Food Science and Technology"],"dc:creator":["Yoder, Jonna D."],"dc:date.accessioned":["2014-03-14T21:40:48Z"],"dc:date.available":["2014-03-14T21:40:48Z","2009-07-21"],"dc:date.issued":["1994"],"dc:description.abstract":["The objective of this study was to use MAP technology to produce safe, shelf-stable, high quality, hard grated cheeses not requiring preservatives or refrigeration during distribution and sale. Initially, a challenge study with Staphylococcus aureus (S. aureus) was conducted to determine the water activity (Aw) level of high-moisture cheeses necessary to prevent the growth of a food pathogen when packaged under a modified atmosphere (25% CO, and 75% N,). Other microbial analysis included mold and yeast enumerations. Secondly, product quality and shelf stability were determined biweekly by sensory, microbial, and instrumental analysis to evaluate product safety and changes in the natural aromas and flavors of hard grated cheeses. Instrument color analysis CIE L* a* b* values were determined to measure color changes. Parmesan cheese with high Aw levels (Aw= 0.90 and 0.88) supported the growth and survival of S. aureus. The microorganism was incapable of surviving at Aw levels of 0.86 and below. S. aureus was not able to survive on Romano cheese. Mold and yeast proliferated on higher Aw Parmesan cheeses. Visible mold was detected on the Parmesan sample of Aw= 0.90 after 8 weeks of storage. No mold growth was observed on Romano cheese. However, yeast were capable of growing on Romano cheese. The sensory evaluation study of hard grated cheeses was unable to detect a difference between the fresh cheese sample and the cheeses packaged under MAP."],"dc:description.degree":["Master of Science"],"dc:format.medium":["BTD"],"dc:format.mimetype":["application/pdf"],"dc:identifier.other":["etd-07212009-040516"],"dc:identifier.uri":["http://hdl.handle.net/10919/43806"],"dc:language.iso":["en"],"dc:publisher":["Virginia Tech"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:title":["Modified atmosphere packaging of hard grated cheeses"],"dc:type":["Thesis"],"dc:type.dcmitype":["Text"],"thesis:degree_discipline":["Food Science and Technology"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:19:01Z"}