红曲霉固体发酵豆粕及其产物分析

红曲霉固体发酵豆粕及其产物分析

刘安军，尚校兰，朱振元，满金浩

（天津科技大学食品工程与生物技术学院，天津 300457）

摘要：以豆粕为原料，利用红曲霉菌株（Monascus purpureus）进行固态发酵，豆粕与水的质量比为1:1时得到的发酵产物的质量较高。并测定了发酵前后的产物色价、蛋白质类型、蛋白质含量、多肽含量及发酵产物中Monacolin K的含量，结果表明红曲霉固体发酵所得豆粕的色价不高；蒸汽加热会使豆粕中的蛋白质变性，溶解度显著降低，红曲霉发酵豆粕的过程使可溶性蛋白质含量增加，且使大分子蛋白质变成小分子肽类，从而提高了蛋白质的功能特性；发酵产物存在莫纳可林K，但含量不高。用红曲霉固体发酵豆粕生产红曲霉色素或莫纳可林K不可取。

关键词：豆粕；红曲霉；发酵；大豆多肽；莫纳可林K

中图分类号：TQ920；文献标识码：A；文章篇号:1673-9078(2009)01-0149-03

Analysis of the Solid-State Fermented Soybean meal by Monascus

LIU An-Jun, SHANG Xiao-Lan, ZHU Zhen-Yuan, MAN Jin-Hao

（College of Food Science and Biotechnology, TianJin University of Science and Technology, Tianjin 300457, China）Abstract: M. rubber (Monascus purpureus) mediated solid state fermentation of the soybean meal was studied. The high-value fermented soybean meal was obtained with the ratio of soybean meal to water being of 1:1. The color-value, the comparison of the protein type, the contents of protein, and the detection of polypeptide before the fermentation and after the fermentation was determined and the contents of Monacolin K in the fermented product were determined. The results showed that the color-value of the solid-state fermented soybean mea was low and the solubility of the protein in the fermented soybean was reduced due to denaturation by steam heating. Through the solid-state fermentation, the contents of the soluble protein increased and the proteins decomposed to peptides and thus improve the function of the protein. Low content of Monacolin K was found in the fermented soybean meal, which indicated that the solid state fermentation of soybean meal by Monascus was unsuitable to the production of Monascus Pigment and Monacolin K.

Key words: soybean meal; monascus; fermentation; soybean polypeptide; Monacolin K

豆粕是目前畜牧养殖业使用量很大的一种优质蛋白源，具有较高的粗蛋白含量及较平衡的氨基酸组成。但由于大豆蛋白质分子结构复杂，分子量较大，存在着消化率和生物学效价不及动物性蛋白质的问题。通过微生物发酵，大豆蛋白能形成大豆多肽和小分子物质的混合物，具有溶解度好、黏度低、比蛋白和氨基酸更易消化等特点[1~3]。

红曲霉(Monascus)广泛应用于食品工业中，红曲色素长期作为食品着色剂；其发酵产物中含多种有效活性物质，其中莫纳可林K(Monacolin K)具有降低血清胆固醇及防癌等功效。本文首次对红曲霉固体发酵豆粕的色价、发酵前后蛋白质类型、含量及Monacolin K的含量进行了研究[4~6]。

1 材料与方法

收稿日期：2008-08-03

作者简介：刘安军，博士，教授，从事食品生物技术教学与科研工作 1.1 材料

豆粕，市售；红曲霉，天津科技大学功能性食品实验室。

1.2 仪器和药品试剂

电热恒温培养箱、HYG-Ha回转式恒温调速摇瓶柜、超净工作台、立式压力蒸汽灭菌器、DZF-6020型真空干燥箱、高速粉碎机、JR-2集热式磁力加热搅拌器、紫外可见分光光度计、Lab Alliance高效液相色谱仪、凯氏定氮装置、DYY-8B型稳压稳流电泳仪、凝胶成像装置、高速离心机、电子精密天平、pH计、土豆、葡萄糖、琼脂条、牛肉浸膏、蛋白胨、酵母浸粉、丙三醇、硝酸钠、硫酸镁、硫酸铜、硫酸钾、浓硫酸、硼酸、氢氧化钠、盐酸、甲醛、乙酸乙酯、甲醇、乙醇。

1.3 红曲霉发酵豆粕粉的制备

1.3.1 红曲霉培养基的活化

PDA斜面培养基的制备：将土豆去皮洗净，切成小块，放在水中[m(土豆):V(水)＝1:5]煮沸0.5 h，用纱

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