發(fā)布時(shí)間：2018-09-14 14:49

【摘要】：中國(guó)作為一個(gè)馬鈴薯大國(guó),每年有大量的馬鈴薯被加工制成淀粉,而在這個(gè)過(guò)程中會(huì)伴隨產(chǎn)生大量的廢棄物如廢薯渣與汁水,其中含有大量的營(yíng)養(yǎng)物質(zhì),直接排放不僅造成資源的大量浪費(fèi),還導(dǎo)致環(huán)境的嚴(yán)重破壞。本研究利用微生物的生長(zhǎng)代謝對(duì)馬鈴薯薯渣進(jìn)行發(fā)酵,并且將纖維素降解過(guò)程與單細(xì)胞蛋白生產(chǎn)相結(jié)合,將原本廢棄的營(yíng)養(yǎng)物質(zhì)進(jìn)行加工利用,生產(chǎn)單細(xì)胞蛋白,制成動(dòng)物喜食的飼料。通過(guò)實(shí)驗(yàn)確定了發(fā)酵菌種生長(zhǎng)特性,找到了復(fù)合微生物發(fā)酵馬鈴薯薯渣的最佳發(fā)酵條件,并且對(duì)發(fā)酵產(chǎn)物進(jìn)行品質(zhì)評(píng)價(jià),最后利用數(shù)學(xué)方法對(duì)發(fā)酵體系進(jìn)行了動(dòng)力學(xué)分析。實(shí)驗(yàn)選擇有纖維素降解能力的黑曲霉、產(chǎn)單細(xì)胞蛋白的釀酒酵母與地衣芽孢桿菌作為發(fā)酵菌種,分別測(cè)定各自生長(zhǎng)曲線,結(jié)合還原糖的產(chǎn)生情況確定了發(fā)酵時(shí)各個(gè)菌種的添加時(shí)機(jī)以保證發(fā)揮最大功效,通過(guò)測(cè)定精蛋白變化情況結(jié)合經(jīng)濟(jì)成本問(wèn)題綜合考慮確定發(fā)酵周期為4天。利用響應(yīng)面優(yōu)化法得到發(fā)酵的最佳條件為p H為6.3,接種量為2.61%,溫度為33.94℃。通過(guò)驗(yàn)證實(shí)驗(yàn),得到實(shí)驗(yàn)值蛋白減少量為3.21 mg/m L,與理論值3.28 mg/m L基本一致。然后建立了有關(guān)馬鈴薯薯渣發(fā)酵的動(dòng)力學(xué)模型,在對(duì)最佳條件下進(jìn)行的發(fā)酵過(guò)程進(jìn)行檢測(cè),利用1stopt軟件對(duì)實(shí)驗(yàn)數(shù)據(jù)進(jìn)行擬合,分別解得菌體生長(zhǎng)動(dòng)力學(xué)、產(chǎn)物生成動(dòng)力學(xué)、動(dòng)物消耗動(dòng)力學(xué)模型的未知參數(shù),確定了完整的數(shù)學(xué)公式,為以后的大型生產(chǎn)提供便利,指導(dǎo)工業(yè)應(yīng)用。測(cè)定經(jīng)過(guò)發(fā)酵處理的汁水對(duì)比原始汁水COD去除率為72.99%。對(duì)發(fā)酵產(chǎn)物物理、化學(xué)、生物方面的品質(zhì)進(jìn)行簡(jiǎn)單評(píng)價(jià),纖維素與蛋白小顆粒在發(fā)酵后被分解破壞,利于動(dòng)物消化,上清液中精蛋白含量由發(fā)酵前的4.58 mg/m L減為發(fā)酵后的1.37mg/m L,粗蛋白含量達(dá)到31.8%,檢測(cè)到的17種氨基酸含量在發(fā)酵后全部增加,總量達(dá)到15.8%,提高5.4倍。纖維素降解率為55.4%,最終還原糖剩余量為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，

本文編號(hào)：2243026