Starch production, industrial

Potato tuber protein complement is of interest to the potato starch industry, because high quantities of proteins can be purified from the potato juice by-product. Thus a number of studies on potato tuber proteins have been performed on cultivars grown for industrial starch production, such as Elkana in The Netherlands and Kuras in Northern Europe. A few studies have been performed on, e g., cvs Desiree and Bintje, which are commonly used for human consumption in Europe. The soluble proteins of potato tuber have been classified broadly into three groups patatins, protease inhibitors, and other proteins (Pots et al., 1999). Patatins and protease inhibitors are well characterized, whereas quite limited information has been available about the other major proteins. 

The main industrial starch productions are based primarily on four resources maize (76%), cassava (12%), wheat (7%) and potatoes (4%). Other forms of starch represent less than 1%. The main production zones are North America (33%), China (33%), Europe (18%), South Asia (11%) and South America (5%). The following set North America, China and Europe represent in total 85% of worldwide starch production. However, those three only correspond to around one-third of the world s population. 

Elbahloul, Y, Frey, K., Sanders, J., Steinbuchel, A., 2005a. Protamylasse, a residual compound of industrial starch production, provides a suitable medium for large scale cyanophycin production Applied and Environmental... 

Starch is a polysaccharide found in many plant species. Com and potatoes are two common sources of industrial starch. The composition of starch varies somewhat in terms of the amount of branching of the polymer chains (11). Its principal use as a flocculant is in the Bayer process for extracting aluminum from bauxite ore. The digestion of bauxite in sodium hydroxide solution produces a suspension of finely divided iron minerals and siUcates, called red mud, in a highly alkaline Hquor. Starch is used to settle the red mud so that relatively pure alumina can be produced from the clarified Hquor. It has been largely replaced by acryHc acid and acrylamide-based (11,12) polymers, although a number of plants stiH add some starch in addition to synthetic polymers to reduce the level of residual suspended soHds in the Hquor. Starch [9005-25-8] can be modified with various reagents to produce semisynthetic polymers. The principal one of these is cationic starch, which is used as a retention aid in paper production as a component of a dual system (13,14) or a microparticle system (15). 

Pyrotechnic mixtures may also contain additional components that are added to modify the bum rate, enhance the pyrotechnic effect, or serve as a binder to maintain the homogeneity of the blended mixture and provide mechanical strength when the composition is pressed or consoHdated into a tube or other container. These additional components may also function as oxidizers or fuels in the composition, and it can be anticipated that the heat output, bum rate, and ignition sensitivity may all be affected by the addition of another component to a pyrotechnic composition. An example of an additional component is the use of a catalyst, such as iron oxide, to enhance the decomposition rate of ammonium perchlorate. Diatomaceous earth or coarse sawdust may be used to slow up the bum rate of a composition, or magnesium carbonate (an acid neutralizer) may be added to help stabilize mixtures that contain an acid-sensitive component such as potassium chlorate. Binders include such materials as dextrin (partially hydrolyzed starch), various gums, and assorted polymers such as poly(vinyl alcohol), epoxies, and polyesters. Polybutadiene mbber binders are widely used as fuels and binders in the soHd propellant industry. The production of colored flames is enhanced by the presence of chlorine atoms in the pyrotechnic flame, so chlorine donors such as poly(vinyl chloride) or chlorinated mbber are often added to color-producing compositions, where they also serve as fuels. 

The paper industry constitutes the largest single industrial market for starch in the world. If the world production of paper is about 235 MM tons, starch production for paper may be estimated at about 3 MM tons. This recognizes that large volume items such as newsprint and tissue are essentially non-starch users. 

Starch is an abundant, inexpensive polysaccharide that is readily available from staple crops such as com or maize and is thus is mostly important as food. Industrially, starch is also widely used in papermaking, the production of adhesives or as additives in plastics. For a number of these applications, it is desirable to chemically modify the starch to increase its hydrophobicity. Starch modification can thus prevent retrodegradation improve gel texture, clarity and sheen improve film formation and stabilize emulsions [108], This may, for example, be achieved by partial acetylation, alkyl siliconation or esterification however, these methods typically require environmentally unfriendly stoichiometric reagents and produce waste. Catalytic modification, such as the palladium-catalyzed telomerization (Scheme 18), of starch may provide a green atom-efficient way for creating chemically modified starches. The physicochemical properties of thus modified starches are discussed by Bouquillon et al. [22]. 

Starch production in Europe is currently constrained by a starch quota system that offers financial incentives to first processors, designed to prevent overproduction in the food sector. Opening up of new industrial market outlets would enable a reassessment of current quota limits imposed on member states, and enable wider participation in starch production across the European Union. 

The paper industry is the main non-food outlet for starch and consumes 17% of the European starch production. Starch-cellulose-starch bonds are created and contribute to the internal cohesion of the paper sheet. 

The high capital and energy costs associated with conventional corn wet-milling, and the continued growth of the industry, has renewed interest in developing alternative starch production methods. These new processes attempt to lower capital and energy requirements and, in some cases, may result in new value-added products. The alternative processes can be divided into processes which decrease diffusion time, which use mechanical shear to enhance separation of starch and protein, and which use a different chemistry to create separation of starch and protein. 

While the major aim in industrial wheat starch production is to produce a refined grade of A-starch, the production of a purified B-starch may also have commercial significance because of its unique uses, as described later in this chapter. In Europe, a new process was developed to separate B-starch into two fractions a high-purity, small granular starch and a feed fraction.53 The process involves enzyme treatment followed by high-pressure treatment and purification on fine screens, separators and decanters. Large and small wheat starch granules are marketed in Japan.85... 

Although potato starch manufacturing is a mature technology, new developments will occur. The market is increasingly demanding a more defined starch quality. Starch production will move from a bulk production industry to a more commodity-oriented industry. This will result in different starch products from the potato process. For example, the Brabender or RVA viscosity or particle size distribution will have narrow specifications. 

Starch for use in papermaking has to meet specific purity requirements in residual oil, protein, bran and ash content. Industrial starches have a protein content (N X 6.25), ranging from about 0.05% for potato starch to 0.3-0.6% for com starch, depending on separation efficiency during production. Excess protein content will induce foaming in dispersions of starch and affect the quality and strength of the coated surface. Starch for use in the paper industry should not contain more than 0.4% protein. Oxidized starches tend to have the lowest protein content. Residual oil will cause retrogradation due to complex formation with amylose. 

Also greatly enlarged and updated is the thorough chapter on the applications of starch products in the paper industry. 

About one-third of the total starch production is used for a variety of industrial purposes that take advantage of its properties (e.g., sizing of paper and board adhesive in the paper, packaging, and textile industries). In the chemical industry, starch is used as a starting material in fermentative processes to produce polyols, acids, amino acids, cyclodextrins, and fructose. 

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