固态发酵法制备苜蓿肽的工艺及其理化特性研究
发布时间：2018-07-31 15:01
【摘要】：苜蓿是一种优质的豆科牧草,富含蛋白质、脂肪、维生素及多种矿物元素,营养成分均衡,是具有潜力的蛋白饲料资源。本研究以降低苜蓿纤维素含量,提高蛋白质和酸溶性肽含量为目的,采用固态发酵方法,选择合适的菌种进行发酵,制备苜蓿蛋白,并进一步以酶解法制备苜蓿肽,同时对苜蓿肽的理化性质进行研究。1.通过优化白腐菌固态发酵苜蓿草粉工艺参数,确定最佳的发酵条件为:料水比1:1.2,发酵时间为72 h,接种量为108 cfu/g,发酵温度是28℃。发酵后,粗纤维含量为11.90%,比未发酵时降低了38.34%;粗蛋白质和真蛋白质含量为29.62%、22.97%,分别比未发酵时提高了42.41%,28.97%;酸溶性小肽的含量升高了12.59%;必需氨基酸和总氨基酸含量均有所增加;2.以啤酒酵母为发酵菌种,固态发酵苜蓿草粉,确定工艺参数。在单因素试验的基础上进行响应面分析设计,得到回归方程为:Y=4.276667+0.165X1+0.73X2+0.2475X3-0.417083X12-0.3025X1X2+0.0025X1X3-0.842083X22-0.3225X2X3-0.577083X32(X1表示料水比,X2表示发酵时间,X3表示发酵温度)。对回归方程求导得知最优条件为:料水比:1:1.52,发酵时间为122.6 h,发酵温度为28.3℃。此时,粗蛋白质的含量为26.81%。通过验证试验可知,实际发酵苜蓿粉的粗蛋白质含量为26.65%,与理论预测值相比,相对误差为0.60%,发酵后的苜蓿粉纤维素含量为15.73%,比未经发酵的苜蓿纤维素含量降低了18.50%,酸溶性小肽的含量提高了69.58%。3.对所获得的发酵苜蓿粉提取苜蓿蛋白,提取条件为料水比1:8,碱提pH为9.0,浸提时间为30 min,浸提温度为45℃,酸沉pH为4.0,得到提取效率为41.25%;4.采用酶解法提取苜蓿肽产品,将发酵样品提取的苜蓿肽与未经发酵的样品提取的苜蓿肽相比,两种产品的起泡性和起泡稳定性没有显著的差别,但是经过发酵的样品提取的苜蓿肽的吸油性和吸水性明显优于未经发酵的样品提取的苜蓿肽;发酵后样品提取的苜蓿肽含有4种多肽,其中在保留时间为6.37 min时的肽含量最高。结果表明经过微生物发酵能够使苜蓿粉的粗蛋白质含量相对增加,降低纤维素含量,提高酸溶性肽含量,从而改善苜蓿粉的饲用品质。
[Abstract]:Alfalfa is a kind of high quality legume forage, which is rich in protein, fat, vitamins and many mineral elements. In order to reduce the content of cellulose and increase the content of protein and acid soluble peptide in alfalfa, alfalfa protein was prepared by solid state fermentation, and alfalfa protein was prepared by enzyme hydrolysis. At the same time, the physicochemical properties of alfalfa peptide were studied. By optimizing the technological parameters of solid state fermentation of alfalfa meal with white rot fungus, the optimum fermentation conditions were determined as follows: the ratio of material to water was 1: 1.2, the fermentation time was 72 h, the inoculation amount was 108 cfur / g, and the fermentation temperature was 28 鈩，
本文编号：2155950
[Abstract]:Alfalfa is a kind of high quality legume forage, which is rich in protein, fat, vitamins and many mineral elements. In order to reduce the content of cellulose and increase the content of protein and acid soluble peptide in alfalfa, alfalfa protein was prepared by solid state fermentation, and alfalfa protein was prepared by enzyme hydrolysis. At the same time, the physicochemical properties of alfalfa peptide were studied. By optimizing the technological parameters of solid state fermentation of alfalfa meal with white rot fungus, the optimum fermentation conditions were determined as follows: the ratio of material to water was 1: 1.2, the fermentation time was 72 h, the inoculation amount was 108 cfur / g, and the fermentation temperature was 28 鈩，
本文编号：2155950
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