| Energy shortage is one of major issue facing this century, generally considered the planet's crude oil resources will be depleted in 50 years. Currently, the increasingly serious situation of domestic energy supply, from the national strategic and energy security considerations, research new energy alternatives to oil is particularly urgent. The development of the use of non-food crops cassava fuel ethanol industry will not only help safeguard the national food, oil security, protect the environment, but also to promote the industrialization of agriculture, in building a new socialist countryside to help farmers to get rich have very bright prospects, in the "three rural" issue has important strategic significance.Traditional use of cassava alcohol production process complexity, high cost, dependent on the equipment, and pollution is more serious. This article on the 60 C oγ-ray irradiation on the impact of cassava starch and use of irradiation no cooking cassava ethanol fermentation was investigated, with results as follows:1. Cassava starch irradiated X-ray diffraction is not essentially different, crystal form has not changed. With the irradiation dose increases, the cassava starch X-ray diffraction peak gradually disappeared and the crystallinity in 400kGy 25.1% after exposure to a minimum. Many particles were irradiated in the erosion and damage occurred, and as the dose increased by a growing number of eroded particles, particle surface with numerous pits, some of the particle surface become rough. To 400kGy, some grains of dishing erosion, fracture, and rupture, a number of particles, "burst" the internal structure exposed. When the irradiation dose 400kGy reached after the dissolution rate of 95.68% and 99.15%.2. Irradiation favor enzymatic hydrolysis of cassava starch.400kGy radiation dose of starch on the initial pH, fermentation temperature and amount of enzyme hydrolysis greatly reduce dependence on liquefied hydrolysis was significantly higher than other groups of irradiated samples and the original starch. Cassava starch is the main component of these changes in the nature of use of cassava fermentation for the follow-up study provided favorable conditions. Hydrolysis of about pH 6.0, the sample a-amylase and the optimum temperature and 55℃were added, and 5U/g, reaction 30min, substrate concentration 40mg·mL-13. Cassava starch 400kGy irradiation, adding enzyme to the fermentation will still be some beneficial effects. Conditions of a single factor, the raw cassava fermentation and fermentation conditions as follows:the temperature is 31℃, material to water ratio of 1:2, the natural state of pH, urea 0.15%,0.2% east addition level; fermentation time should be 80h-96 h chosen a more favorable context; rotational speed of the fermentation is not very clear4. Using Plackett-Burman factorial experiment and response surface methodology combined with the test methods for non-irradiated cassava ethanol fermentation process of cooking conditions were optimized, the best conditions were:radiation dose 400kGy, feed water ratio 1:2.1 natural state of the initial pH, yeast 0.2%, enzyme (glucoamylase 200U/g, amylase 5U/g), fermentation temperature 30℃, culture fermentation fermentation 98h, ethanol concentration up to about 12.1%. Compared with traditional, large-scale:energy conservationUse of radioactive 60C o issued by the high-energyγ-irradiation treatment, the raw cassava fermentation without cooking not only reduce equipment investment and a significant savings in energy consumption, greatly reducing the cost of ethanol production. Full-text for future large-scale production and application provides a theoretical basis. |
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