{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/70103"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/70103","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Physiological and Biochemical Characterization of Yeasts Active in the Degradation of Cheese Whey to Glycerol, Ethanol and 2,3-Butylene Glycol","abstract":"This research has involved determining to what extent specific yeast strains typically employed in the food industry, utilize lactose and produce commercially useful by-products. Cheese whey is largely a waste product of the dairy industry which contains approximately 5% lactose, and its untreated disposal contributes a massive biological oxygen demand on municipal sewage treatment plants.","abstract_html":"This research has involved determining to what extent specific yeast strains typically employed in the food industry, utilize lactose and produce commercially useful by-products. Cheese whey is largely a waste product of the dairy industry which contains approximately 5% lactose, and its untreated disposal contributes a massive biological oxygen demand on municipal sewage treatment plants.","abstract_has_math":false,"creators":["Jenq, Wheamei"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Food Science","degree_department":null,"school":null,"contributors":["Speckman, Ray A."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014-12-15T21:10:18Z","date_published":"2014-12-15T21:10:18Z","updated_at":"2026-07-22T22:26:02Z","subjects":["Agriculture, Food Science and Technology","Biology, Microbiology"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["(UMI)AAI8823156"],"render_values":[{"text":"(UMI)AAI8823156","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/70103","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Speckman, Ray A."]},{"key":"dc:creator","label":"Author","values":["Jenq, Wheamei"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2014-12-15T21:10:18Z","10000-01-01","1988"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Food Science"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Agriculture, Food Science and Technology","Biology, Microbiology"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/70103","(UMI)AAI8823156"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["This research has involved determining to what extent specific yeast strains typically employed in the food industry, utilize lactose and produce commercially useful by-products. Cheese whey is largely a waste product of the dairy industry which contains approximately 5% lactose, and its untreated disposal contributes a massive biological oxygen demand on municipal sewage treatment plants.","A variety of yeast strains were analyzed for their abilities to achieve the above objectives, and to characterize their growth under experimental conditions, their ability to utilize varied carbon and nitrogen sources, their morphology with electron microscopy, their response to antibiotics, and their DNA ultraviolet absorbance and denaturation curves. A comparison was made of the $\\beta$-galactosidase activities of a Candida kefyr isolate (designated as strain K-201), and in different strains of Kluyveromyces fragilis--both of which showed abilities to utilize lactose. The enzyme was found to be constitutive in C. kefyr and inducible in K. fragilis.","Attempts were made, with limited success, to obtain genetically-modified yeasts, by fusion processes and by transformation, to show greater activity in either lactose utilization or in by-product formation. While the techniques used were proven feasible, it was concluded that the pre-existing strain of K. fragilis (CBS 397, obtained from The Netherlands) showed the most efficient lactose utilization, and was the best butanediol and glycerol producer.","It was found that K. fragilis CBS 397 was a nonhalophilic yeast which only produced high glycerol levels when grown under anaerobic conditions, and optimum yields of glycerol only occurred in the presence of 1% Na$\\sb2$SO$\\sb3$ as a steering agent. The use of other concentrations of Na$\\sb2$SO$\\sb3$, as well as the use of 5% NaCl or 1% ascorbic acid had no, or even detrimental, effects on cell growth, lactose utilization and glycerol production. Also, glycerol yields were greater in cultures grown from a light inoculum of K. fragilis rather than from resuspended cell masses. Optimally, lactose from the medium was effectively degraded after 45 hour post-inoculation, and glycerol yields of 25% were obtained.","Made available in DSpace on 2014-12-15T21:10:18Z (GMT). No. of bitstreams: 1 8823156.pdf: 5229855 bytes, checksum: a65e1ee7cb1c9edb07670b831a5654e1 (MD5) Previous issue date: 1988","Embargo set by: Seth Robbins for item 70269 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","171 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1988."]},{"key":"dc:title","label":"Title","values":["Physiological and Biochemical Characterization of Yeasts Active in the Degradation of Cheese Whey to Glycerol, Ethanol and 2,3-Butylene Glycol"]}]}],"canonical_facts":{"dc:contributor":["Speckman, Ray A."],"dc:creator":["Jenq, Wheamei"],"dc:date":["2014-12-15T21:10:18Z","10000-01-01","1988"],"dc:description":["This research has involved determining to what extent specific yeast strains typically employed in the food industry, utilize lactose and produce commercially useful by-products. Cheese whey is largely a waste product of the dairy industry which contains approximately 5% lactose, and its untreated disposal contributes a massive biological oxygen demand on municipal sewage treatment plants.","A variety of yeast strains were analyzed for their abilities to achieve the above objectives, and to characterize their growth under experimental conditions, their ability to utilize varied carbon and nitrogen sources, their morphology with electron microscopy, their response to antibiotics, and their DNA ultraviolet absorbance and denaturation curves. A comparison was made of the $\\beta$-galactosidase activities of a Candida kefyr isolate (designated as strain K-201), and in different strains of Kluyveromyces fragilis--both of which showed abilities to utilize lactose. The enzyme was found to be constitutive in C. kefyr and inducible in K. fragilis.","Attempts were made, with limited success, to obtain genetically-modified yeasts, by fusion processes and by transformation, to show greater activity in either lactose utilization or in by-product formation. While the techniques used were proven feasible, it was concluded that the pre-existing strain of K. fragilis (CBS 397, obtained from The Netherlands) showed the most efficient lactose utilization, and was the best butanediol and glycerol producer.","It was found that K. fragilis CBS 397 was a nonhalophilic yeast which only produced high glycerol levels when grown under anaerobic conditions, and optimum yields of glycerol only occurred in the presence of 1% Na$\\sb2$SO$\\sb3$ as a steering agent. The use of other concentrations of Na$\\sb2$SO$\\sb3$, as well as the use of 5% NaCl or 1% ascorbic acid had no, or even detrimental, effects on cell growth, lactose utilization and glycerol production. Also, glycerol yields were greater in cultures grown from a light inoculum of K. fragilis rather than from resuspended cell masses. Optimally, lactose from the medium was effectively degraded after 45 hour post-inoculation, and glycerol yields of 25% were obtained.","Made available in DSpace on 2014-12-15T21:10:18Z (GMT). No. of bitstreams: 1 8823156.pdf: 5229855 bytes, checksum: a65e1ee7cb1c9edb07670b831a5654e1 (MD5) Previous issue date: 1988","Embargo set by: Seth Robbins for item 70269 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","171 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1988."],"dc:identifier":["http://hdl.handle.net/2142/70103","(UMI)AAI8823156"],"dc:subject":["Agriculture, Food Science and Technology","Biology, Microbiology"],"dc:title":["Physiological and Biochemical Characterization of Yeasts Active in the Degradation of Cheese Whey to Glycerol, Ethanol and 2,3-Butylene Glycol"],"dc:type":["text"],"thesis:degree_discipline":["Food Science"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:26:02Z"}