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Brewer's grain is the the brewery largest byproduct. In this thesis, brewer's grains as the research object, using pretreatment technologies, enzymatic and probiotic fermentation technology degradable fiber content of brewer's grain, improved protein quality, improve the feeding value of brewer's grain. On the brewer's grain protein and fiber components of the preliminary analysis, determination of the brewer's grain nutrients; using steam explosion, ultrafine grinding, enzymatic hydrolysis pretreatment technology of brewer's grain pretreatment pretreatment before and after brewer's grains fiber morphology, fiber components, and reducing sugar changes; feeding study and optimize the best conditions for cellulase hydrolysis of brewer's grains; preliminary study brewer's grains fermentation conditions, and brewer's grains fermentation effect, the final fattening pigs feeding trials. The results showed that: 13.4% of the brewer's grain crude fiber, neutral detergent fiber (NDF) 49.2%; does not exist significant differences in the the beer lees protein content between batches, and the true protein content accounted for about 88% of the crude protein content, brewer's grains ideal raw material that can be developed as a high-value-added protein feed. Steam explosion pretreatment techniques can effectively destroy the fibrous structure of the lees, so the pore structure was more relaxed, reducing the NDF content, and to improve the content of reducing sugars in the lees. The best conditions for enzymatic hydrolysis of brewer's grain: enzyme concentration of 180U / g, substrate concentration 10%, temperature 50 ° C, the reaction time was 6h; steam explosion after the brewer's grains after enzymatic hydrolysis, reducing sugar The net increase amounted to 12.77 mg / mL. Brewer's grain optimum fermentation conditions for the material to water ratio of 1:1, fermentation agent inoculation 50g/40kg dry worse, the enzyme preparations the added amount 50g/40kg dry worse, fermentation temperature was controlled at 25 to 37 ° C, fermentation time for 7d the best around; fermented dry brewer's grain compared to the original, brewer's grains after steam explosion pretreatment and add complex enzyme, the beer lees NDF from 67.8% down to 35.6%, a decrease rate of 47.5%, fiber degradation effect is very significant ; growth in soluble nitrogen from 35.3mg / L to 617.2mg / L, an increase of approximately 16 times. The amino acid composition of fermented brewer's grains is more comprehensive, more content, more balanced level of brewer's grain nutrition. Finally, feeding experiments found that the proportion of fermented brewer's grains add up to 26.1%, did not significantly affect the growth performance of fattening pigs, no significant difference in the various stages of feed intake, slaughter weight mean there is no significant difference; Add fermented brewer's grains with the feed material weight is lower than the control group, the feed cost per kg weight gain than the control group decreased by 1.055 yuan.
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