{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/80180"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/80180","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Optimization of sweet sorghum processing parameters","abstract":"Production of fuel ethanol from renewable biomass sources has gained popularity in recent years. Sweet sorghum is one of the crops identified as an efficient producer of the sugars needed for ethanol production. The juice in the sweet sorghum pith contains the greatest proportion of nonstructural carbohydrates, the presumed fermentable material. Sugar cane milling procedures have previously been used to extract the juices from the sweet sorghum plant material. The research reported herein relates to a new method of juice extraction expected to provide higher juice expression efficiencies than previous methods. The sweet sorghum stalks are chopped and the sugar-laden pith fraction is separated from the fibrous rind-leaf. The pith portion only is then fed through a screw press for juice extraction. Several chopping and separating parameters were evaluated. A statistical linear regression analysis was employed to evaluate the effects of feed rate, cutting interval, chopper knife speed, and percent of whole stalk mass segregated into the pith category on juice yield. The analysis revealed that the pith category had the most significant positive effect on juice yield calculated as a percent of whole stalk mass. The highest pith categories provided optimization of juice expression. Feed rate has a negative effect on juice yield, meaning that slower feed rates were better, but this was the least significant parameter. The chopping interval had a positive effect, meaning that the largest value used in the analysis provided for optimum juice yield. The cutting speed parameter has no effect on juice yield.","abstract_html":"Production of fuel ethanol from renewable biomass sources has gained popularity in recent years. Sweet sorghum is one of the crops identified as an efficient producer of the sugars needed for ethanol production. The juice in the sweet sorghum pith contains the greatest proportion of nonstructural carbohydrates, the presumed fermentable material. Sugar cane milling procedures have previously been used to extract the juices from the sweet sorghum plant material. The research reported herein relates to a new method of juice extraction expected to provide higher juice expression efficiencies than previous methods. The sweet sorghum stalks are chopped and the sugar-laden pith fraction is separated from the fibrous rind-leaf. The pith portion only is then fed through a screw press for juice extraction. Several chopping and separating parameters were evaluated. A statistical linear regression analysis was employed to evaluate the effects of feed rate, cutting interval, chopper knife speed, and percent of whole stalk mass segregated into the pith category on juice yield. The analysis revealed that the pith category had the most significant positive effect on juice yield calculated as a percent of whole stalk mass. The highest pith categories provided optimization of juice expression. Feed rate has a negative effect on juice yield, meaning that slower feed rates were better, but this was the least significant parameter. The chopping interval had a positive effect, meaning that the largest value used in the analysis provided for optimum juice yield. The cutting speed parameter has no effect on juice yield.","abstract_has_math":false,"creators":["Weitzel, T. Timothy"],"institution":"Virginia Polytechnic Institute and State University","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Agricultural Engineering","degree_department":"Agricultural Engineering","school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1987,"date_issued":"1987","date_published":"1987","updated_at":"2026-07-22T22:20:43Z","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/10919/80180","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.department","label":"Department","values":["Agricultural Engineering"]},{"key":"dc:creator","label":"Author","values":["Weitzel, T. 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Sweet sorghum is one of the crops identified as an efficient producer of the sugars needed for ethanol production. The juice in the sweet sorghum pith contains the greatest proportion of nonstructural carbohydrates, the presumed fermentable material. Sugar cane milling procedures have previously been used to extract the juices from the sweet sorghum plant material. The research reported herein relates to a new method of juice extraction expected to provide higher juice expression efficiencies than previous methods. The sweet sorghum stalks are chopped and the sugar-laden pith fraction is separated from the fibrous rind-leaf. The pith portion only is then fed through a screw press for juice extraction. Several chopping and separating parameters were evaluated. A statistical linear regression analysis was employed to evaluate the effects of feed rate, cutting interval, chopper knife speed, and percent of whole stalk mass segregated into the pith category on juice yield. The analysis revealed that the pith category had the most significant positive effect on juice yield calculated as a percent of whole stalk mass. The highest pith categories provided optimization of juice expression. Feed rate has a negative effect on juice yield, meaning that slower feed rates were better, but this was the least significant parameter. The chopping interval had a positive effect, meaning that the largest value used in the analysis provided for optimum juice yield. The cutting speed parameter has no effect on juice yield."]},{"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":["Optimization of sweet sorghum processing parameters"]}]}],"canonical_facts":{"dc:contributor.department":["Agricultural Engineering"],"dc:creator":["Weitzel, T. Timothy"],"dc:date.accessioned":["2017-11-09T21:09:33Z"],"dc:date.available":["2017-11-09T21:09:33Z"],"dc:date.issued":["1987"],"dc:description.abstract":["Production of fuel ethanol from renewable biomass sources has gained popularity in recent years. Sweet sorghum is one of the crops identified as an efficient producer of the sugars needed for ethanol production. The juice in the sweet sorghum pith contains the greatest proportion of nonstructural carbohydrates, the presumed fermentable material. Sugar cane milling procedures have previously been used to extract the juices from the sweet sorghum plant material. The research reported herein relates to a new method of juice extraction expected to provide higher juice expression efficiencies than previous methods. The sweet sorghum stalks are chopped and the sugar-laden pith fraction is separated from the fibrous rind-leaf. The pith portion only is then fed through a screw press for juice extraction. Several chopping and separating parameters were evaluated. A statistical linear regression analysis was employed to evaluate the effects of feed rate, cutting interval, chopper knife speed, and percent of whole stalk mass segregated into the pith category on juice yield. The analysis revealed that the pith category had the most significant positive effect on juice yield calculated as a percent of whole stalk mass. The highest pith categories provided optimization of juice expression. Feed rate has a negative effect on juice yield, meaning that slower feed rates were better, but this was the least significant parameter. The chopping interval had a positive effect, meaning that the largest value used in the analysis provided for optimum juice yield. The cutting speed parameter has no effect on juice yield."],"dc:description.degree":["Master of Science"],"dc:format.mimetype":["application/pdf"],"dc:identifier.uri":["http://hdl.handle.net/10919/80180"],"dc:language.iso":["en_US"],"dc:publisher":["Virginia Polytechnic Institute and State University"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:title":["Optimization of sweet sorghum processing parameters"],"dc:type":["Thesis"],"dc:type.dcmitype":["Text"],"thesis:degree_discipline":["Agricultural Engineering"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:20:43Z"}