【作者】 王丽娟；

【导师】 吴凤清； 邹博；

【作者基本信息】 吉林大学 ， 物理化学， 2013， 硕士

【摘要】 我国是世界上农业生产大国，每年产出的水稻要超过两亿吨。米糠是稻谷加工时产生的主要副产品，其总量要超过一千万吨。但目前我国大部分的米糠仍用作动物饲料，少部分用来提取米糠油，而米糠中有很多的营养成分，如蛋白质、维生素、纤维素、菲汀等，其价值没有被充分的开发和利用，所以有效充分的利用米糠资源具有极其重要的经济效益和现实意义。米糠中所含有的蛋白质约为12%~18%，是公认的优质植物蛋白质，具有很高的营养价值，其必需氨基酸的种类齐全，组成接近人体需要量模式，还有其它谷物蛋白所不具有的低过敏性。脱脂米糠中的菲汀含量约10%左右，其在农业、医药化工、食品等其他行业都有广泛的用途。所以从米糠中提取出蛋白质和菲汀，剩余的米糠渣再用作动物饲料，这样不但可以增加米糠的附加值，又提高了米糠的利用率，可以实现米糠的综合利用。本论文采用碱法提取米糠蛋白，考察了pH、温度、液固比、反应时间、米糠粒度以及米糠的脱脂处理等因素对米糠蛋白提取的影响，获得了米糠蛋白提取的最佳条件；采用酸浸碱沉法提取米糠菲汀，考察了pH、温度、液固比、反应时间、米糠粒度等因素对菲汀提取量及含磷量的影响，得到菲汀提取的最佳条件，同时也考察了超声辅助提取及常温浸泡方式提取米糠菲汀的效果；探索了米糠蛋白和菲汀连续提取的可行性，考察了米糠蛋白提取时的pH、温度以及脱脂处理的情况对米糠菲汀提取的影响。结论如下：(1)米糠蛋白提取的实验中，得到最佳的提取条件为pH为10，温度50℃，液固比为10，反应时间为2小时，得到蛋白质的提取率为26.1%。以低沸点的醚类脱脂处理的米糠蛋白质的提取率最高，米糠的粒度以过筛40目为最佳。(2)米糠菲汀提取的最佳条件为pH为2，温度为25℃室温，液固比为10，磁力搅拌时间为3小时，得到菲汀的提取量为0.8736g，磷含量为0.3365g。(3)从第四章的实验说明从米糠中连续提取蛋白质和菲汀是可能的，并通过几个因素条件的反应得到了蛋白质提取对菲汀的一些影响关系。更多还原

【Abstract】 China is a large agricultural country in the word. The annual output of rice hasreached more than two hundred million tons. Rice bran is a by-product of riceprocessing, it’s total output is more than ten million tons. But most of the rice bran isused as animal feed, only a small part is used to extract rice bran oil. Although ricebran have a lot of nutrients, such as protein, vitamins, cellulose, phytin, etc. its valuehas not been fully developed and utilized, so effective utilization of the rice branresources is extremely important to economic and practical significance.The protein content of rice bran is about12%to18%, which is recognized as ahigh quality plant protein and has a high nutritional value. Meanwhile, it almostcontains all essential amino acids, closed to human requirements, as well ashypoallergenic protein which other grain protein does not have. The phytin content ofdefatted rice bran contains about10%, which have a wide range of use in agriculture,pharmaceutical chemical industry, food and other industries. The rice bran protein andphytin are extracted from the rice bran, and then the remaining residue of rice brancan be used as animal feed. The process can increase the added value of rice bran andimprove the comprehensive utilization.In this paper we use alkaline solution to extract the rice bran protein, andexplore the influence factors on the rate of protein extraction which contain pH,temperature, the ratio of liquid to solid, reaction time, rice bran particle size, as wellas the defatted processing of the rice bran, and get the optimum conditions for proteinextraction; In succession, we use the dilute acid plus alkali to extract rice bran phytin,and investigate the influences such as pH, temperature, liquid to solid ratio, reactiontime, rice bran particle size, etc. on the extraction quantity of phytin and phosphoruscontent, and then get the optimum conditions for phytin extraction. At the same time,we also investigated the experiment results of the ultrasound-assisted extraction androom temperature soak to extract rice bran phytin. Finally, we investigate the continuous extraction of bran protein and phytin, and discuss the influences of thepH、temperature of the protein extraction、defatted processing to the protein andphytin extraction. Conclusions are as follows:(1) According to experiments, we got the optimum conditions of the rice branprotein extraction which are as follow: pH is10, temperature is50℃, the ratio ofliquid to solid is10, the reaction time is2hours. And the protein extraction rate is26.1%. The extraction rate of the rice bran which is defatted by the low-boiling ethersis the highest, and the best size of rice bran is less than40mesh.(2) The best extraction conditions of bran phytin are as follows: pH value is2,the temperature is25℃, the ratio of liquid to solid is10, the stirring time is3hours.We got0.8736g phytin and0.3365g phosphorus.(3) According to the experiments of chapter4, the continuous extraction of ricebran protein and phytin from rice bran is possible. And we get the influencerelationship that protein extraction to phytin by several reactions which have differentconditions.更多还原