Location: Commodity Utilization Research
2008 Annual Report
Brown, dry (BL) and green leaves (GL) from a commercial, Louisiana sugarcane variety LCP 85-384, were laid outside under simulated field canopy shade and allowed to deteriorate for 14 days under dry (control) and water sprayed (wet) conditions. The 14-day sampling period was repeated three times across the 2007 Louisiana processing season (Oct to Dec) to cover weather variations. The worst deterioration for both BL and GL occurred under wet conditions, but humidity levels were more critical to bacterial and yeast deterioration of GL than BL. After deterioration of more soluble impurities, including color compounds, which are detrimental to factory processing, were extracted from GL, whereas less were usually extracted from BL. During the drier periods (Oct and Nov), BL color decreased on deterioration, whereas BL color increased in the wetter period (Dec). Percent fiber in GL always increased on deterioration. For BL, % fiber fluctuated more than for GL, but was always lower under wet conditions.
At the end of the 2006 processing season, hard-to-boil massecuites, (HTB), normal massecuites, and molasses were collected from four Louisiana factories. Compared to normal samples, the HTB samples had 9-33% lower heat conductivity and 10-49% higher heat resistivity. Excess lime addition during juice clarification is not the direct cause of reduced ability to boil. In contrast to the normal samples, strong gel networks were present in the HTB samples explaining the difficulty to remove water on factory boiling. As HTB samples contained considerably greater total soluble polysaccharides (long chain sugars) than the normal samples, a polysaccharide is likely the cause of the gel network. Initial results suggested the presence of an arabinogalactan and endo-dextranase resistant dextran polysaccharides. An enzyme (a compound that speeds-up a chemical reaction) to breakdown the HTB polysaccharide was identified. Mannitol (a sugar alcohol) is also a contributor, but not the sole cause of the phenomenon.
The American Sugar Cane League was kept informed of the progress of the grant with informal meetings. A final report will be sent to the American Sugar Cane League at the end of the grant.
This project is the in-house project to the Trust Agreement with the American Sugar Cane League, 6435-41000-095-04T, "Weather Effects on the Processing Properties of Different Sugarcane Trash and How to Alleviate Them" and the Specific Cooperative Agreement with the Sugar Processing Research Institute, 6435-41000-095-01S, "Characterization on Improvements of Sugarcane and Sugarbeet Process Units." Additional information about progress on this work can be found in the subordinate project reports.
There is a shift in U.S. harvesting from burnt to unburnt sugarcane, and unburnt leaves deteriorate, which impact sugar processing. Three studies (during the processing season) were performed to determine how brown and green sugarcane leaves degraded under dry and wet conditions. It was determined that deterioration occurred mainly under wet conditions and that deteriorated green leaves contributed significantly to soluble impurities, negatively affecting processing. These results will provide information about how sugar processing must be modified to alleviate processing problems.
This accomplishment addressed The NP 306 Action Plan, Component 1, Quality Characterization, Preservation and Enhancement, Problem area 1c “Factors and processes that affect quality.”2. Determined the Cause of Hard-to-Boil Massecuites in Sugarcane Factories.
Hard-to-boil massecuites with markedly low heat transfer properties are a sporadic but continuing problem in U.S. sugarcane factories causing decrease in raw sugar yield and, on occasions, factory shut-downs. Samples were evaluated from four Louisiana factories and it was determined that elevated soluble polysaccharides may cause gel network and lower heat conductivity/higher heat resistivity. An enzyme capable of degrading an important polysaccharide was identified. This research will allow better control of this difficult problem at factories.
This accomplishment addressed the NP 306 Action Plan, Component 1, Quality Characterization, Preservation and Enhancement, Problem area 1b “Methods to evaluate and predict quality”.
5.Significant Activities that Support Special Target Populations
Zhou, M., Kimbeng, C.A., Eggleston, G., Viator, R.P., Hale, A.L., Gravois, K.A. 2008. Issues of Starch in Sugarcane Processing and Prospects of Breeding for Low Starch Content in Sugarcane. Sugar Cane International. 26(3):3-13.
Eggleston, G., Karr, J.R., Parris, A., Legendre, B. 2008. Viability of an enzymatic mannitol method to predict sugarcane deterioration at factories. Journal of Food Chemistry. 111:476-482.
Eggleston, G., Montes, B., Monge, A., Guidry, D. 2008. Optimization of alpha-amylase application in raw sugar manufacture. part I: characterization of commercial alpha-amylases. International Sugar Journal. 110(1310):97-104.
Eggleston, G., Montes, B., Monge, A., Guidry, D. 2007. Optimization of amylase application in raw sugar manufacture. part II: factory trials. International Sugar Journal. 109(1305):579-584.