Starch bioethanol production

The compactness and complexity of (ligno)cellulose makes it much more difficult to attack by enzymes with respect to starch. Therefore, the cost of bioethanol production is higher [23], To be cost competitive with grain-derived ethanol, the enzymes used for biomass hydrolysis must become more efficient and far less expensive. In addition, the presence of non-glucose sugars in the feedstock complicates the fermentation process, because conversion of pentose sugars into ethanol is less efficient than conversion of the hexose sugars. 

Bioethanol production by yeasts is widely used for biodegradation of potato. However, yeasts cannot ferment starch directly, and a two-step enzymatic reaction to glucose is necessary. Different potato wastes such as industrial residues, low-grade potatoes, and spoiled potatoes can be used for acetone/ethanol production (Nimcevic et al., 1998). They used whole potato media... 

Bioethanol Production from Uncooked Raw Starch by Immobilized Surface-engineered Yeast Cells... 

Bioethanol produced from biomass resources by fermentation is the most promising biofuel and the starting material of various chemicals. Starch is a cheap, clean, nontoxic, renewable Ccirbon source for bioethanol production [1]. In the process currently employed for industrial-scale ethanol production from starchy materials, starch is first hydrolyzed by adding a liquefying enzyme, a-amylase (EC 3.2.1.1), to avoid gelatinization and then... 

The results presented in this paper were only a very preliminary study of pretreatment of maize silage. Trials should be made at lower temperatures to examine if more energy could be saved in the process. It would also be interesting to determine the content of starch and cellulose separately by enzymatic hydrolysis, instead of total glucan as is the case in this study. Also, enzymatic hydrolysis and SSF using low enzyme loadings (of both cellulases and amylases) should be made to fully see the potential of this promising raw material for bioethanol production. 

Worldwide, ethanol is mostly produced by fermentation, accoimt-ing for up to 90% of ethanol produced globally. In Brazil, most bioethanol is produced from sugarcane or molasses and in the United States from com. However, other starch materials such as wheat, barley and rye are also suitable as raw material. The starch-containing grains have to be converted into sugar. Thus, in Europe, starch grains, e.g., wheat and sugar beet are the major source of bioethanol production (15). 

Du YY, Fang HH, Zheng PW (2013) Porous sepiolite/starch composites Preparation, structure and absorption properties. Adv Mat Res 1937 634-638 Duquesne E, Moins S, Alexandre M, Dubois P (2007) How can nanohybrids enhance polyester/ sepiolite nanocomposite properties Macromol Chem Phys 208 2542-2550 Duran N, Lemes AP, Duran M, Freer J, Baeza J (2011) A mini review of cellulose nanocrystals and its potential integration as co-product in bioethanol production. J Chil Chem Soc 56 672-677... 

The cereal seeds, tubers, starch storage roots, and bean/pea seeds are directly consumed as food in human diet or animal feed and are used as a source of starch. Extracted starch can be used to produce starch derivates or hydrolyzed to produce soluble sugars, food additives, or glucose syrup. Also, extracted starch can be used for other applications in nonfood industries (Nghiem et al. 2011). For example, it is used as a thickener and as a source of renewable raw material for bioethanol production. The major source of starch for the world market is cornstarch holding more than 80 % of the market, but wheat, potato, cassava or tapioca, and to a lesser extent rice and sweet potato starches are also commercialized (Thomsen et al. 2008). 

The production of biofuels and bio-based chemicals is now well established. Several enterprises all over the world have initiated the commercial production of energy/fuel and chemicals from renewable sources. The annual bioethanol production is reported to be between 100,000 and 300,000 tons per year from Cg sugar platform biorefinery (lEA, 2013). In Europe, most of these biorefineries use multifeedstock, primarily sugar or starch crops, whereas in the United States most of the biorefineries use sugarcane and com (lEA,... 

There is around 60 million tons of raw starch produced annually for food and nonfood uses. The major sources of starch include rice, wheat, potatoes, cassava (tapioca), and com, which accounts for over 80% of the world production. Com is used in the United States as a fermentation feedstock for bioethanol production, discussed later in this chapter. Starch is produced by steeping the raw material in hot water, which releases the starch from the binders also present in the biomass. 

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