Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: February 14, 2005
Publication Date: March 14, 2005
Citation: Eggleston, G. 2005. Razoes para a destruiçao de açúcar durante o processamento de cana [abstract]. Session 3, 26th meeting of Fermentec, Sao Pedro, Sao Paulo State, Brazil, March, 2005, Fermentec Publication. p. 4-5. Technical Abstract: The thermal destruction or degradation of sugars, particularly sucrose, glucose and fructose, and the formation of colored and non-colored degradation products, is of considerable technical importance to the sugarcane industry. This is not only because of expensive losses of sugar, but also because of the reduction in efficiencies of various unit processes and end product quality. In Brazil, the destruction of sugars can affect not only sucrose yields but alcohol yields too. This paper discusses the mechanisms of the degradation of sucrose, glucose and fructose in acid and alkaline solution, as they apply to sugarcane processing. In general, the acid degradation of sucrose (often referred to as sucrose inversion) occurs much more easily than the alkaline degradation of sucrose. Invert sugars (glucose and fructose), the products of sucrose acid degradation, are far more reactive in alkali (pH greater than 7.0) than acid. In acid, the rate of degradation of sucrose is faster than the rate of degradation of its inversion products. In alkali, the rate of degradation of sucrose is much less than the rate of degradation of glucose or fructose, and color formation from the alkaline degradation of invert sugars is relatively high. Impurities such as salts and invert sugars themselves can increase the thermal degradation rate of sucrose, and the industrial implications of this are discussed. Examples of industrial losses of sugars across clarification and evaporation processes are also included, to highlight the extent to which sucrose losses occur, and the importance of pH and Brix control to minimize unwanted losses.