{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/53492"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/53492","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"A study of the causes of periodic abnormalities of a high grade pasteurized milk supply","abstract":"The causes of acid liquefaction in a high grade pasteurized milk were investigated. 1. Liquefying milk produced much less acid and had a much lower plate count than normal milk. 2. <i>Bacillus albolactis</i> was found regularly in the milk. It made up a much larger percentage of the total flora in liquefying than in normal milk. 3. Associated growth experiments showed that <i>Strep. lactis</i> could control the liquefying activities of <i>Bacillus albolactis</i>. 4. Pasteurization experiments showed that milk heated for 20 minutes at temperatures higher than 61°C. would undergo acid liquefaction. This appeared to be due to the increase in the percentage of <i>Bacillus albolactis</i>. 5. Inoculation of pasteurized samples with <i>Strep. lactis</i> prevented acid liquefaction. 6. Comparison with a type species showed that the strains of <i>Strep. lactis</i> repeatedly isolated from the milk studied were of the <i>tardus</i> variety. 7. The liquefaction was probably primarily due to an increased percentage of <i>Bacillus albolactis</i> brought about by pasteurization; the lack of the type of species of <i>Strep. lactis</i> and the absence of lactobacilli might also have been contributing factors.","abstract_html":"The causes of acid liquefaction in a high grade pasteurized milk were investigated. 1. Liquefying milk produced much less acid and had a much lower plate count than normal milk. 2. &lt;i&gt;Bacillus albolactis&lt;/i&gt; was found regularly in the milk. It made up a much larger percentage of the total flora in liquefying than in normal milk. 3. Associated growth experiments showed that &lt;i&gt;Strep. lactis&lt;/i&gt; could control the liquefying activities of &lt;i&gt;Bacillus albolactis&lt;/i&gt;. 4. Pasteurization experiments showed that milk heated for 20 minutes at temperatures higher than 61°C. would undergo acid liquefaction. This appeared to be due to the increase in the percentage of &lt;i&gt;Bacillus albolactis&lt;/i&gt;. 5. Inoculation of pasteurized samples with &lt;i&gt;Strep. lactis&lt;/i&gt; prevented acid liquefaction. 6. Comparison with a type species showed that the strains of &lt;i&gt;Strep. lactis&lt;/i&gt; repeatedly isolated from the milk studied were of the &lt;i&gt;tardus&lt;/i&gt; variety. 7. The liquefaction was probably primarily due to an increased percentage of &lt;i&gt;Bacillus albolactis&lt;/i&gt; brought about by pasteurization; the lack of the type of species of &lt;i&gt;Strep. lactis&lt;/i&gt; and the absence of lactobacilli might also have been contributing factors.","abstract_has_math":false,"creators":["Rubin, Benjamin Arnold"],"institution":"Virginia Agricultural and Mechanical College and Polytechnic Institute","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Biology","degree_department":"Biology","school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1938,"date_issued":"1938","date_published":"1938","updated_at":"2026-07-22T22:18:52Z","subjects":[],"languages":["en_US"],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10919/53492","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.department","label":"Department","values":["Biology"]},{"key":"dc:creator","label":"Author","values":["Rubin, Benjamin Arnold"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2015-06-23T19:12:24Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2015-06-23T19:12:24Z"]},{"key":"dc:date.issued","label":"Date","values":["1938"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Agricultural and Mechanical College and Polytechnic Institute"]},{"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":["Biology"]},{"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 Agricultural and Mechanical College and Polytechnic Institute"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en_US"]},{"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.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/53492"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The causes of acid liquefaction in a high grade pasteurized milk were investigated. 1. Liquefying milk produced much less acid and had a much lower plate count than normal milk. 2. <i>Bacillus albolactis</i> was found regularly in the milk. It made up a much larger percentage of the total flora in liquefying than in normal milk. 3. Associated growth experiments showed that <i>Strep. lactis</i> could control the liquefying activities of <i>Bacillus albolactis</i>. 4. Pasteurization experiments showed that milk heated for 20 minutes at temperatures higher than 61°C. would undergo acid liquefaction. This appeared to be due to the increase in the percentage of <i>Bacillus albolactis</i>. 5. Inoculation of pasteurized samples with <i>Strep. lactis</i> prevented acid liquefaction. 6. Comparison with a type species showed that the strains of <i>Strep. lactis</i> repeatedly isolated from the milk studied were of the <i>tardus</i> variety. 7. The liquefaction was probably primarily due to an increased percentage of <i>Bacillus albolactis</i> brought about by pasteurization; the lack of the type of species of <i>Strep. lactis</i> and the absence of lactobacilli might also have been contributing factors."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["A study of the causes of periodic abnormalities of a high grade pasteurized milk supply"]}]}],"canonical_facts":{"dc:contributor.department":["Biology"],"dc:creator":["Rubin, Benjamin Arnold"],"dc:date.accessioned":["2015-06-23T19:12:24Z"],"dc:date.available":["2015-06-23T19:12:24Z"],"dc:date.issued":["1938"],"dc:description.abstract":["The causes of acid liquefaction in a high grade pasteurized milk were investigated. 1. Liquefying milk produced much less acid and had a much lower plate count than normal milk. 2. <i>Bacillus albolactis</i> was found regularly in the milk. It made up a much larger percentage of the total flora in liquefying than in normal milk. 3. Associated growth experiments showed that <i>Strep. lactis</i> could control the liquefying activities of <i>Bacillus albolactis</i>. 4. Pasteurization experiments showed that milk heated for 20 minutes at temperatures higher than 61°C. would undergo acid liquefaction. This appeared to be due to the increase in the percentage of <i>Bacillus albolactis</i>. 5. Inoculation of pasteurized samples with <i>Strep. lactis</i> prevented acid liquefaction. 6. Comparison with a type species showed that the strains of <i>Strep. lactis</i> repeatedly isolated from the milk studied were of the <i>tardus</i> variety. 7. The liquefaction was probably primarily due to an increased percentage of <i>Bacillus albolactis</i> brought about by pasteurization; the lack of the type of species of <i>Strep. lactis</i> and the absence of lactobacilli might also have been contributing factors."],"dc:description.degree":["Master of Science"],"dc:format.mimetype":["application/pdf"],"dc:identifier.uri":["http://hdl.handle.net/10919/53492"],"dc:language.iso":["en_US"],"dc:publisher":["Virginia Agricultural and Mechanical College and Polytechnic Institute"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:title":["A study of the causes of periodic abnormalities of a high grade pasteurized milk supply"],"dc:type":["Thesis"],"dc:type.dcmitype":["Text"],"thesis:degree_discipline":["Biology"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Agricultural and Mechanical College and Polytechnic Institute"]},"updated_at":"2026-07-22T22:18:52Z"}