【作者】 何强飞；

【导师】 郭贯新；

【作者基本信息】 江南大学 ， 粮食、油脂与植物蛋白工程， 2008， 硕士

【摘要】 本论文以大米饲料蛋白为原料,对原料的预处理、酶法制备蛋白肽的工艺、大米蛋白肽液的精制以及产品成分分析等进行了系统的研究。旨在充分利用大米饲料蛋白资源,制备高纯度的大米蛋白多肽,为相关企业提供大米蛋白肽原材料,生产出更多更好的大米蛋白肽产品,提升传统食品的科技水平。为稻谷资源的深度开发和利用提供有力依据和技术支持。主要研究结果如下:研究了超微粉碎和水洗对原料颗粒粒径分布、蛋白肽提取率、蛋白含量和蛋白损失产生的直接和间接影响。结果显示,在电流频率为80Hz的气流粉碎机下粉碎30min,物料粒径能粉碎到800目左右,D50=11.03μm。超微粉碎改变了原料的粒径分布,促进了原料中有效成分的溶出。用超微粉碎蛋白粉进行酶解,蛋白肽提取率达到68.3%,比原料的提取率高20%左右;原料通过水洗,可以将其中的大部分杂质成分溶解而除去。提高了原料中有效成分的利用率。水洗的最佳条件为:液固比7:1(V/W),温度60℃,时间60min,水洗二次。此条件下的蛋白含量可达85.86%,而蛋白损失率仅为3.67%。研究了我国现阶段已经商品化的三种微生物蛋白酶(碱性蛋白酶、中性蛋白酶和酸性蛋白酶)水解大米饲料蛋白的工艺。所用微生物蛋白酶具有活性高、来源广泛、价格低廉和适合工业化生产等特点,具有广阔的应用前景。确定了酶的最佳水解工艺:碱性蛋白酶1.0%(E/S),中性蛋白酶0.4%(E/S),酸性蛋白酶0.4%(E/S),料液比1:10(W/V),起始pH10.5,50℃恒温水解6h。得出大米饲料蛋白的提取率为74.58%。以除去大米蛋白肽液中的色素和盐分为目的,系统研究了用活性炭脱色和用阴阳离子交换柱脱盐的工艺条件。结果显示,活性炭和离子交换柱能有效地脱色和脱盐,能够达到工业上需要的水平。最佳工艺为:①pH为6,温度50℃,活性炭用量2%(W/W),脱色30 min。脱色率达到80.16%,肽损失率为8.27%。②将肽液以10倍柱体积/ h的流速流经阴阳离子交换柱时,阳离子交换柱和阴离子交换柱的的肽回收率分别为82.29%和80.92%左右,脱盐率达到82.18%。利用氨基酸分析仪和凝胶色谱柱对大米多肽粉进行了氨基酸分析和肽分子量分布的测定。结果显示,大米多肽粉的总蛋白含量为83.6%(干基)。其中多肽占75.7%(干基),游离氨基酸占4.3%(干基)。在蛋白肽的组成结构中,大部分肽是由3-6个氨基酸组成的,分子量在1000以下。大米多肽得率为50.12%,肽纯度为71.01%。大米多肽的溶解度达到98.53%。所得大米多肽具有很好的溶解性和色泽。更多还原

【Abstract】 This paper used rice feed protein as raw material, made a series of study about raw materials for the pretreatment, Enzymatic extraction of the protein and rice peptide, Refiner of rice peptide and analysis of product components. Designed to take full advantage of the rice feed protein resources, preparation of high-grade rice protein peptide, producing more and better products, improving science and technology level of traditional food and providing a strong basis and technical support for the depth exploiture and the use of rice resources.Key findings are as follows:Study direct and indirect effect of advanced micro comminution and washed pretreatment method to raw material particle size, content and the loss of protein. In the frequency of 80 Hz ,the smash time is 30 min, particle size can smash to about 800 head, D50=11.03μm. advanced micro comminution change in the size distribution of raw materials, promote the dissolution of active ingredient. Advanced aicro comminution with the crush of raw materials for enzyme, its extraction rate is 68.3%, 20 percent is better than extraction of raw materials. Raw materials by the washing, can remove the ineffective components.Increase the utilization of raw materials active ingredients. The best condition of washing is: liquid-solid is 7:1, the temperature of 60℃, time 60min, washed secondary. Under these conditions the extraction is up to 85.86 percent, and the loss rate of protein only 3.67%. Research has been using to the three-microbial protein enzyme which is commercialize- tion in China’s current stage. Protease is used by the microbial activity, source of widespread, cheap and suitable for industrial production, and other features, will have broad application prospects. Determine the best extraction process: Basic protease -1.0%-0.4% neutral protease, acid protease -0.4%, solid-liquid is 1:10, starting pH10.5,50℃temperature hydrolysis 6 h,come to rice feed protein extraction rate of 74.58 percent.To remove the rice-liquid solution of salt and pigment for the purpose ,study the process conditions by system analysis of the use of activated carbon decolorization and yin and yang with ion exchange column desalination. The results showed that activated carbon and ion exchange column effective decoloring and desalination, to achieve the level of industrial needs. Optimum process conditions:①pH 6, the temperature of 50℃, the amount of activated carbon 2 percent, decolorizing 30 min.Decolo- rate reached 80.16 percent, the peptide loss rate to 8.27 percent.②enzyme solution to be 10 times the speed-volume flows through the ion exchange column of yin and yang, desalination rate of 82.18 percent and 80.92 percent and 8.27 percent rice peptide is loss.Use of amino acid analyzer instrument and gel products for amino acid analysis and the molecular weight arrangement of rice peptide. The total protein content of rice peptides products is 83.6 percent (dry weight), Which accounted for 75.7 percent peptide (dry weight), free amino acids accounted for 4.3 percent (dry weight).In the composition of the structure of peptide products, the majority peptide is composed by 3-6 amino acids, the molecular weight of the following in 1000. Rice peptide in the rate of 50.12 percent, 71.01 percent for the peptide purity. The solubility of rice peptides reached 98.53 percent. Peptide from the rice has a good solubility and color.更多还原