|Waguespack, Jr., Herman|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/12/2010
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: In sugar manufacture, there is a trend in the United States and world-wide to produce very high purity (VHP) and very low color (VLC) raw sugars for vertical integration from the field to the refinery. New refineries in Louisiana (LA) are expected to be operational in the next few years. One of these refineries requests lower ash concentrations in the VHP/VLC sugar for liquid sugar manufacture and short, medium, and long-term refinery strategies. Great variations in the color and quality of raw and VHP/VLC sugars exist mostly because of the range in quality of the cane supply (Muir and Eggleston, 2009, SIT paper #960). Strategies to control the quality of the cane supply will largely depend on the quantity, quality and type of sugarcane trash (leaves and top) processed at factories which, in turn, will strongly be affected by seasonal variations. This study was undertaken to ascertain the variations in juice quality parameters that affect VHP/VLC manufacture and refining across the Louisiana 3-month processing season (late Sept to Dec) in 2009. Across the season, air temperature decreased and there was slight but consistent rainfall. Juice was extracted from separated stalk (S), growing point region (GPR or top), green leaf (GL) and brown leaf (BL) tissues of three popular sugarcane varieties (HoCP 96-540, L 99-226 and L 99-233), six times between Sept and Dec 2009. For all three varieties, total trash decreased across the season but GL levels were consistently higher in HoCP 96-540, and by Dec total trash was lowest in L 99-226. As expected, theoretical sugar recovery and juice purity values of stalks increased across the season. There was a strong varietal difference for starch. Unlike in previous years with an older variety, starch processed at LA factories now increases up to the end of Nov and decreases in Dec. This suggests the need for breeding programs to include quality parameters as selection criteria. In the U.S., premiums for low color in sugar are paid on color measured at pH 8.5 whereas the rest of the world measures ICUMSA color at pH 7.0. In this study, color at pH 8.5 accentuated varietal differences in juice more than at pH 7.0 and was also more sensitive to GPR and GL colorants that are responsible for causing the color of raw, VHP/VLC and affinated sugars (Muir and Eggleston, 2009, SIT paper #960). Fiber did not vary considerably across the season for all varieties. Ash was highest in all tissues at the beginning of the season (Oct 9), decreased in the middle of the season then increased again at the end of the season. Leaf moisture, juice extraction and tissue pH variations are also discussed.