Starch crops

The following characterization of starch crops describes maize, potatoes, wheat, and other cereals in more detail. Another significant source for starch is rice. However, cultivation is both technically and traditionally concentrated in Asia, so rice is mainly imported into Europe as food and so far does not play a role as renewable raw material (for rice straw, see Section 4.2.2.4). Table 4.3 gives an overview for selected starch crops in terms of characteristics and production statistics. 

Maize (Zea mays) is part of the cereals, a group of grasses taxonomically belonging to the Poaceae family. It is an annual crop that can reach a height of 4 m. Corncobs represent the female inflorescences and develop 8-18 rows of 25-50 kernels. The C4 plant has a starch content of about 62% (fresh matter) [15]. 

Maize is an important source for human nutrition, and is consumed either directly or as processed foods such as tortillas or porridge (19). Maize starch is 

Solanum tuberosum is a species of the Solanaceae family. The pereimial, cross-pollinated plant reaches a height of about 80 cm and develops white or purple flowers and a thick characteristic tuber. The tuber has a starch content of about 15% (fresh matter) consisting of 79% amylopectin and 21% amylose [10]. 

About 10% of the potato input for starch processing results in potato pulp. In addition to starch, this pulp contains cellulose, hemicellulose, pectin, and protein. 

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Energy crops Short-rotation woody crops, herbaceous woody crops, grasses, starch crops, sugar crops, forage crops, oilseed crops, switchgrass, miscanthus... 

An alternative to the utilization of food crops in biofuel production is lignocellu-lose, which can for instance be utilized in biomass-to-liquid (BTL) processes. That way, a direct competition between food and fuel production can be avoided. This feedstock is much more abundant than vegetable oils or sugar and starch crops. 

Agricultural, wood, and urban wastes, crop residue Wood, logging residues, trees, shrubs Starch crops such as corn, wheat, and barley, sugar crops, grasses, vegetable oils, hydrocarbon plants e.g. Pittos-porum resiniferum, Euphorbia lathyris)... 

Feedstock Options. Ethanol may be produced via fermentation (with yeast) of 6-carbon or 12-carbon sugars from a number of carbohydrate sources including sugar crops, starch crops, or lignocellulosic materials. 

Most current commercial ethanol production is from the fermentation of sugar and starch crops. Yeast can rapidly convert sucrose to ethanol with a theoretical carbon conversion of 67%. The production of ethanol from corn grew to about 1.9 billion gallons in 2001. This accounted for 90% of the total ethanol production and an estimated 615 million bushels of corn (6.2% of total corn produced) were consumed. The remaining 10% of ethanol production was by fermentation of grain sorghum, barley, wheat, cheese whey, and potatoes. 

Starches as a group, and the three principal volume starches, individually, are by far the most important polysacolloids on both a weight and a money basis. They are also the cheapest polysaccharides in most areas of the world, the major exception being the Orient, where starch crops are more valuable as food and so are replaced, in other usages, by less easily assimilated polysacolloids. Com (maize) is the most important starch crop in this country (accounting for over 90 % of the total production of starch), followed by potatoes and wheat whereas, in Europe, the production of potato and wheat starch far exceeds that of corn. 

Bioethanol is preferentially made from cellulosic biomass materials instead of from more expensive traditional feedstock such as starch crops. Obtaining it from sugar-feedstock is even... 

Table 4.3 Overview characteristics and production statistics of selected starch crops. 

Wheat is one of the most important food crops in the world but its usage is not limited to nutritional products. Industrial applications are comparable to other starch crops and include adhesives, biomaterials, and ethanol production [10]. 

Oats are other important feed crops for cattle and especially for horses, while good health effects are also appreciated increasingly in human nutrition. With appUcations in paper and adhesives businesses, industrial usage resembles that of other starch crops [25]. 

World production of the main starch crops in 2005 (1 X 1000 metric tons), (Source FAO, 2005 [11])... 

Preparation of starch nanocrystal-reinforced NR nanocomposites is often by the solution mixing method. The general steps are depicted as follows the first step is preparation of starch nanocrystals. Starch nanocrystals were usually extracted from natural starch crops (such as maize,cassava, potato, wheat, eZc.) by hydrolysis in the presence of strong acids (such as sulfuric acid or hydrochloric acid).The second step is the mixing of the starch nanocrystal... 

Starch Crop Raffination Oilseed Crops LignoceUulosic Feedstock... 

The milling process is applicable to both the sugar and starch crops. In the case of sugar crops, the sugar juices are extracted from the bagasse, which is... 

Both starch crops and lignocellulosics contain polymers of sugars that can be broken down into monomers and used in fermentation. The federally-subsidized production of fuel ethanol from com is an example of bioconversion that takes advantage of well-established wet and dry milling techniques after which the starch is enzymatically converted to glucose for yeast fermentation. 

C6 sugar platform biorefinery for bioethanol and animal feed from starch crops... 

Due to the seasonality and the very different biological structure of starch crops, starch production technologies depend on the type of raw material. Cereals can easily be stored in a grain elevator, which is why cereal starch can be produced throughout the year, whereas tuber and root-starch must be produced immediately after the harvest of the crop. 

Starch crop biorefineries based on cereals, maize, potato, etc. 

Starch crop biorefineries During starch production, several residues emerge. Generally, the proteins need to be separated from the starch. These are often used for animal nutrition. In potato starch produaion, additionally, wash water is produced, and in starch production from corn and cereals fibers remain. 

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