Evaluation of Storage Techniques to Preserve Fermentable Sugars from Sugar Beets for Ethanol Production

• Main Author: Vargas-Ramirez, Juan Manuel
• Format: Others
• Published: North Dakota State University 2017
• Subjects: Biomass energy.; Feeds.
• Online Access: https://hdl.handle.net/10365/26618

New sugar beet varieties may qualify as an advanced biofuel feedstock in the U.S., but new alternatives to conventional pile storage are necessary to preserve fermentable sugars and allow yearlong beet ethanol production. Fermentable sugar preservation was assessed in sugar beets stored under aerobic and anaerobic atmospheres and in raw thick juice stored at acidic (2≤ pH≤ 5) and alkaline (8≤ pH≤11) conditions. Aerobic storage of sugar beets at 4°C for 14 wk resulted in higher fermentable sugar retention (99± 4%) than at 25°C or anaerobic storage at 4° C and 25° C. Raw thick juice retained ≥ 99% of fermentable sugars at pH 3.5 and 9.5 and refractometric dissolved solids content of 64.5° Bx. The changes in fermentable sugars in raw thick juice stored for 24 wk at acidic and alkaline pH were modeled by response surface methodology. Although raw thick juice was stored successfully at acidic and alkaline pH, conditions for high-efficiency fermentation must be developed.