复合微生物发酵薯渣条件优化
发布时间：2018-09-14 14:49
【摘要】：中国作为一个马铃薯大国,每年有大量的马铃薯被加工制成淀粉,而在这个过程中会伴随产生大量的废弃物如废薯渣与汁水,其中含有大量的营养物质,直接排放不仅造成资源的大量浪费,还导致环境的严重破坏。本研究利用微生物的生长代谢对马铃薯薯渣进行发酵,并且将纤维素降解过程与单细胞蛋白生产相结合,将原本废弃的营养物质进行加工利用,生产单细胞蛋白,制成动物喜食的饲料。通过实验确定了发酵菌种生长特性,找到了复合微生物发酵马铃薯薯渣的最佳发酵条件,并且对发酵产物进行品质评价,最后利用数学方法对发酵体系进行了动力学分析。实验选择有纤维素降解能力的黑曲霉、产单细胞蛋白的酿酒酵母与地衣芽孢杆菌作为发酵菌种,分别测定各自生长曲线,结合还原糖的产生情况确定了发酵时各个菌种的添加时机以保证发挥最大功效,通过测定精蛋白变化情况结合经济成本问题综合考虑确定发酵周期为4天。利用响应面优化法得到发酵的最佳条件为p H为6.3,接种量为2.61%,温度为33.94℃。通过验证实验,得到实验值蛋白减少量为3.21 mg/m L,与理论值3.28 mg/m L基本一致。然后建立了有关马铃薯薯渣发酵的动力学模型,在对最佳条件下进行的发酵过程进行检测,利用1stopt软件对实验数据进行拟合,分别解得菌体生长动力学、产物生成动力学、动物消耗动力学模型的未知参数,确定了完整的数学公式,为以后的大型生产提供便利,指导工业应用。测定经过发酵处理的汁水对比原始汁水COD去除率为72.99%。对发酵产物物理、化学、生物方面的品质进行简单评价,纤维素与蛋白小颗粒在发酵后被分解破坏,利于动物消化,上清液中精蛋白含量由发酵前的4.58 mg/m L减为发酵后的1.37mg/m L,粗蛋白含量达到31.8%,检测到的17种氨基酸含量在发酵后全部增加,总量达到15.8%,提高5.4倍。纤维素降解率为55.4%,最终还原糖剩余量为0.015mg/m L。
[Abstract]:China, as a large potato country, has a large number of potatoes processed into starch every year, and in the process, it will produce a lot of waste such as waste potato dregs and juices, which contains a lot of nutrients. Direct emissions not only lead to a large amount of waste of resources, but also lead to serious damage to the environment. In this study, potato dregs were fermented by microbial growth and metabolism, and the cellulose degradation process was combined with the production of single cell protein, and the waste nutrients were processed and utilized to produce single cell protein. Feed that makes animals like to eat. The growth characteristics of fermentation bacteria were determined by experiments, the optimum fermentation conditions of potato dregs by compound microorganism were found, and the quality of the fermentation products was evaluated. Finally, the kinetics of the fermentation system was analyzed by mathematical method. Aspergillus Niger with cellulose degradation ability, Saccharomyces cerevisiae and Bacillus licheniformis, which produce single cell protein, were selected as fermentation strains, and their growth curves were measured. Combined with the production of reducing sugar, the adding time of each strain during fermentation was determined to ensure the maximum effect. The fermentation period was determined to be 4 days by determining the changes of protamine and considering the economic cost. By using response surface optimization method, the optimum fermentation conditions were as follows: ph was 6.3, inoculation amount was 2.61 and temperature was 33.94 鈩，
本文编号：2243026
[Abstract]:China, as a large potato country, has a large number of potatoes processed into starch every year, and in the process, it will produce a lot of waste such as waste potato dregs and juices, which contains a lot of nutrients. Direct emissions not only lead to a large amount of waste of resources, but also lead to serious damage to the environment. In this study, potato dregs were fermented by microbial growth and metabolism, and the cellulose degradation process was combined with the production of single cell protein, and the waste nutrients were processed and utilized to produce single cell protein. Feed that makes animals like to eat. The growth characteristics of fermentation bacteria were determined by experiments, the optimum fermentation conditions of potato dregs by compound microorganism were found, and the quality of the fermentation products was evaluated. Finally, the kinetics of the fermentation system was analyzed by mathematical method. Aspergillus Niger with cellulose degradation ability, Saccharomyces cerevisiae and Bacillus licheniformis, which produce single cell protein, were selected as fermentation strains, and their growth curves were measured. Combined with the production of reducing sugar, the adding time of each strain during fermentation was determined to ensure the maximum effect. The fermentation period was determined to be 4 days by determining the changes of protamine and considering the economic cost. By using response surface optimization method, the optimum fermentation conditions were as follows: ph was 6.3, inoculation amount was 2.61 and temperature was 33.94 鈩，
本文编号：2243026
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