Raw SugarBy Bento, Luis San Miguel Posted on 2006-09-18 Last edited on 2010-12-16
Raw sugar is the product obtained in cane sugar mills. In the mills, the juice extracted from sugar cane is purifyed and after crystallization a brownish sugar is produced, the raw sugar. In the past, beet sugar industry also produced raw sugar, as in cane industry. Nowadays high purity white sugar is produced directly from sugar beets in beet factories. However, in cane sugar industry, raw sugar produced in cane sugar mills must be re-processed in re
Typical analysis Polarisation Reducing Sugars Ash Humidity Granulometry MA CV Colour Colur in the crystal IV Starch Dextran
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98.5 Z 0.50% 0.30% 0.30% 0.70 mm 40 4500 IU 2100 IU 2.2 120 ppm 400 ppm |
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Raw sugar, containing normally between 97.5 and 99.5% of sucrose, presents a brownish yellow colour and a crystal size about 1mm MA (mean aperture). A syrup layer, containing the great part of these colourants, covers the sucrose crystals. This layer is separated in the first refining operation, Affination. Other part of colurants will remain in the crystals. In the last decades, raw sugar quality has evolved from a Pol of 96º in the sixties of XX century, till the VHP (very high pol) raw with a Poll higher than 99º. Recently, in Australia, a new raw sugar type was produced, the VLC sugar, presenting a high Pol and a low colour (Burns and Field, 1998). The objective of VLC production is to transfer to the mills the majority of the purification process. With this process, in refineries, VLC is melted, filtered and crystallized, avoiding affination and decolourization processes. Recovery section can also be avoided if residual refined syrup is used to produce liquid sugar or soft sugars, as areado sugar.
Bibliography
Bruns P., P.J. Fields, 1998, The very low colour sugar story, Proc. SIT Conf., 117-133 Carreno P.A., 1980, Raw sugar quality standards - A Producers point of view, Proc. SIT Conf., 160-176 Clarke M.A., R.S. Blanco, M.A. Godshall, 1984, Color tests and other indicators of raw sugar refining characteristics, Proc. of S.P.R.I. Conf., 2284-302 Godshall M.A., M.A. Clarke, E.J. Roberts, 1987, Large colorant and polysaccharide molecules in raw cane sugars, Proc. of S.I.T. Conf., 193-211 O’Shea M.G., P.F. Lindeman, 2001, High Molecular colourants and their impact on the refinability of raw sugar. A study of Australian and overseas raw sugars, Proc. of Aust. S.S.C.T. Conf., 23, 322-329 King S.L., 2005, Raw cane sugar quality from producers perspective, Proc. of S.I.T. Conf.,101-109 Meadows D.M.,P.M. Schorn, M.Moodley, S.D. Peacock, A. Bindorf, 2005, South African experiences with raw sugar quality, Proc. of S.I.T. Conf., 110-120 Murray J.P., F.M. Rungass, 1974, Filtering quality of raw sugar: Mechanisms of starch influence in carbonatation, Proc. of I.S.S.C.T., 1296-1306 Paton N.H., 1992, The origin of colour in raw sugar, Proc. of Aust. S.S.C.T. Conf., 14, 8-17
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