Posts Tagged ‘Sugar Technology’
Abstract
Dextranase only have a small market and low volume sales compared to many other industrial enzymes. Consequently, research and development efforts to engineer properties of dextranase to specific conditions of industrial processes have not occurred and are not expected soon. This book chapter highlights the difficulties associated with the practical application of dextranases, that are sometimes applied to hydrolyze dextran in sugar manufacture when bacterial deterioration of sugarcane or sugarbeet has occurred. Less than optimum application existed because of confusion about where to add the dextranase in the factory/refinery and which commercial dextranase to use. The wide variation in activity of commercially available dextranase in the U.S., and a standardized titration method to measure activities at the factory are discussed. Optimization by applying “concentrated” dextranase as a working solution to heated juice is described. Promising short-term technologies to further improve industrial dextranase applications are discussed, as well as the long-term outlook.
Gillian Eggleston · Adrian Monge · Belisario Montes · David Stewart
Sugar Tech (2009) 11(2) : 135-141
By :
By R.K Goyal, Rajesh Khosla, Pravin Goel
Jindal Stainless Limited
Corrosion of sugar manufacturing equipment has been among the most important concern of the plant operation in the sugar industry. Stainless steel has emerged as the most suitable material for overcoming most of the problems associated with the sugar industry. This paper is an attempt to explore the various application in the industry with a view to minimizing the life cycle costs for the industry.
What are Stainless Steels
Stainless steels grades are essentially alloys of iron with more than 11% of Chromium These grades may contain additional elements like nickel, manganese, carbon, nitrogen, silicon, etc. They can further be modified for special purposes by addition of molybdenum, titanium, niobium, silicon, sulphur, etc. A wide range of these grades have been developed based on specific requirements. These are classified into following categories based on their microstructure:
Corrosion in Sugar Industry
Most of the equipment is made in Sugar industry from Mild steel. This has resulted in the corrosion becoming a major factor to be addressed in the Sugar industry. Color in sugar due to Iron Oxide: In India, plantation white sugar is manufactured, where, generally no further refining is carried out. Therefore it is important to minimize color imparting impurities (corrosion) in the process equipment. It is estimated that about 20-25 kg equivalent of Fe2O3 is mixed in the juice for every 1000 tones of Cane processed through sulphitation process. (Source: P Honig, Principles of Sugar Technology Part-I). Due to this corrosion, the color of juice darkens resulting in loss of whiteness. Read the rest of this entry »
By :
Efraín Rodríguez Jiménez
E–mail: efrain.rodriguez@cigb.edu.cu
ABSTRACT
In sugar production, dextrans are undesirable compounds synthesized by contaminant microorganisms from sucrose, increasing the viscosity of the flow and reducing industrial recovery, bringing about significant losses. The use of the dextranase enzyme is the most efficient method for hydrolyzing the dextrans at sugar mills. Some bacterial strains, filamentous fungi and a small number of yeasts have been shown to produce dextranase. The fungal dextranases showed the highest reaction rate at low Brix, with pH and temperature close to 5.0 and 50 ºC, respectively, that is, conditions existing in juice extraction. Some of these dextranases formulated in enzymatic preparations have been efficiently used for hydrolyzing dextrans in sugar mill juices. In more advanced points of the process, where the dextrans have already caused losses, the conditions of temperature and Brix are high.
However, although the volumes are smaller, the treatment with these enzymes in syrup showed the need to increase the dose, equaling dextranase consumption. Some thermo tolerant bacterial dextranases identified up to now showed a much reduced specific activity that makes their industrial use unfeasible. The fungal dextranases from Chaetomium sp. have shown the best results on dextrans treatment both in juices and syrups. Any attempt to obtain a new natural or recombinant dextranase enzyme, must be comparable with to the Chaetomium enzyme.
Keywords: Dextranase, industrial enzymes, industrial application, dextran
For full article please see links bellow :
http://elfosscientiae.cigb.edu.cu/PDFs/BA/2005/22/1/BA002201RV020-027.pdf
