膜分离制取可溶性菜籽蛋白及其对DPPH自由基的清除作用

采用碱提取酸沉淀方法和膜分离技术从菜籽粕制取沉淀蛋白和可溶性蛋白,研究蛋白产物中的硫甙和植酸分布、膜分离操作对可溶性蛋白的硫甙和植酸含量的影响、以及可溶性蛋白的抗氧化活性。结果表明,沉淀蛋白得率较低,需要回收可溶性蛋白。菜籽粕中的硫甙被碱液提取并主要集中于可溶性蛋白,膜分离可以明显降低可溶性蛋白中的硫甙含量,经CF=4 及DV=3 的膜分离,得到的可溶性蛋白中的硫甙含量仅为0.11mg/g。可溶性蛋白还具有清除DHPP 自由基活性的作用。碱液不能有效提取菜籽粕中的植酸,大部分植酸残留在提取蛋白后的残渣中,膜分离难以分离可溶性蛋白中的植酸。     

菜籽饼粕生物转化与高值化利用技术研究进展

菜籽饼粕是一种利用价值很高的优质植物蛋白资源。由于饼粕中存在硫甙、芥酸、植酸等多种有害成分和抗营养因子,其利用价值和应用范围受到极大限制。生物技术法对于改善饼粕饲用品质、提升综合利用价值、拓宽应用领域等方面具有独特的优势。本文重点介绍了生物技术法在饼粕脱毒、饲用品质改良、发酵生产食用菌和酶制剂等产品的生物转化与高值化利用方面的最新研究进展,并概述了生物技术法应用于饼粕的发展方向。     

响应面法优化草酸钾溶液提取菜籽饼中植酸工艺

菜籽饼是提取植酸的良好原料,植酸具有独特的生物活性.采用草酸钾溶液提取菜籽饼中的植酸,在单因素试验的基础上,通过响应面法优化植酸提取工艺,建立了以草酸钾溶液提取植酸的二次多项数学模型,并得到最佳工艺条件为:pH 8,液料比14∶1,草酸钾溶液浓度0.075 mol/L,提取时间5h.经过验证试验,在最佳工艺条件下,植酸得率为1.81％.     

菜籽粕中抗营养因子及其去除方法的研究进展

油菜籽加工过程中的副产品菜籽粕具有广阔的应用前景,然而由于菜籽粕中硫代葡萄糖甙以及其他一些抗营养因子的存在,使菜籽粕的合理利用受到制约.论述了菜籽粕中的抗营养物质及其毒害作用和去除这些抗营养物质的方法.菜籽粕中的抗营养物质主要有硫代葡萄糖甙及其降解产物、植酸、单宁和芥子碱,可采用物理方法、化学方法、生物方法和遗传学方法对菜籽粕进行脱毒.     

菜籽预榨-浸出粕中植酸的提取

为实现菜籽粕的综合开发利用,研究了一种从菜籽预榨-浸出粕中两步提取植酸的工艺.考察了酸洗pH、酸洗时间、碱提pH和碱提乙二胺四乙酸二钠(EDTA)浓度等对植酸提取的影响.将经过复合纤维素酶水解的菜籽粕在pH 5.0和50℃下酸洗3h获得酸洗液,然后用EDTA浓度0.1mol/L的碱性溶液在pH 12.0和50℃下碱提酸沉获得乳清液,经以上两步可将菜籽粕中的植酸基本提取完全.将提取液中的粗植酸经氢氧化钙沉淀并酸化,再经离子交换可获得纯度为69.96％、提取率为58.0％的植酸产品.     

Fate of phytic acid during bread making

The effect of malt addition and yeast concentration on the hydrolysis of phytic acid during different stages of bread making has been reported. There was a considerable hydrolysis of phytic acid with the addition of yeast and malt. In the breads of S-308 and WL-711 wheat varieties, the loss of phytic phosphorus was 6.6. 8,1; 24.6, 23.0 and 26.6, 27.7% in case of nonyeasted, 1.5% and 3% yeasted dough of whole wheat flour (Atta) respectively. However in white bread, the loss of phytic phosphorus was 14.0 and 18.4; 46.2 and 41.5; 51.7 and 49.4%, in non-yeasted, 1.5% and 3% yeasted doughs of S-308 and WL-711 wheat varieties respectively. A significant loss of phytic acid was observed at a yeast level of 1.5 and 3% and with 0.4% malt addition as compared with the control. Most of the phytic acid was hydrolysed during the fermentation and proofing stages in both types of bread samples.     

双液相萃取菜籽粕蛋白的萃取沉淀特性

本文以双液相萃取菜粕为研究对象，测定了不同ｐＨ下菜粕中蛋白质、植酸和总磷的溶解曲线以及室温下蛋白质的沉淀曲线。试验表明，在４０℃，ｐＨ＝１２时，双液相萃取粕蛋白质萃取率为７．１５％，植酸萃取率为３３．６％。双液相萃取粕蛋白质的等电点在ｐＨ＝４～６，ｐＨ＝５时蛋白质沉淀率为７２．１％。     

脱壳菜籽饼粕生产植酸新工艺的研究

研究表明脱壳菜籽饼粕脱毒液中含有大量的矿物离子.提取植酸时无须加入外源阳离子沉淀植酸,利用其本身舍有的阳离子,调整溶液pH即可沉淀出植酸盐.最佳参数为:用3%盐酸室温下浸提45min.浸提2次后用NaOH溶液调节溶液的pH至9～10,弃去溶液后用0.3mol/L盐酸溶解沉淀,以2%BV/min流速流过732型阳离子树脂交换柱,再以2%BY/min的流速流过D315树脂上柱吸附,以2mol/L HCl按3%BV/min的流速洗脱植酸,产品得率91.10%,纯度为76.84%.     

菜籽粕脱毒液中植酸的提取及其抗氧化活性

采用碱沉淀法从菜籽粕脱毒液中回收提取植酸并对该制备植酸的抗氧化活性进行研究。以BHT为阳性对照,考察植酸对猪油的酸价和过氧化值的影响;采用流动化学发光法和可见分光光度法,以VC为阳性对照,考察植酸清除羟自由基( ·OH)、超氧阴离子自由基(O2 ·)、1, 1-二苯基-2-苦苯肼自由基(DPPH自由基)及H2O2的能力。结果表明：回收提取植酸以NaOH调节溶液pH8为优,得率达92.83%,植酸含量为45.96%;植酸对猪油的酸败和过氧化有一定的抑制作用且优于BHT;制备植酸(实验制备)清除各种自由基的能力依次为：O2 ·＞ ·OH＞H2O2＞DPPH自由基,且除DPPH自由基外对其他自由基清除效果均优于VC。表明植酸是一种较好的天然抗氧化剂。     

Rapeseed protein polyanion interactions —Turbidimetric studies in systems with phosphate-containing polyanions: phytic acid and octametaphosphate

The interaction of two main protein fractions of rapeseed —the 12 S globulin and the low-molecular albumin fraction —with two phosphate-containing polyanions —phytic acid and octametaphosphate (OMP) —has been studied using turbidimetric titration and chemical analysis after precipitation. Both proteins form insoluble complexes with the polyanions below the isoelectric point. The globulin is precipitated quantitatively by both polyanions at pH 3.0. A precipitation of more than 90% of the albumin occurs by OMP, while phytic acid precipitates only 80% of this protein at pH 3.0. Increasing amounts of polyanions over the precipitation points result in a partial solubilization of albumin-polyanion complexes. The amount of polyanions bound to the proteins increases with decreasing pH. A (1:1)-stoichiometry of phytic acid binding on the globulin has been found at pH 3.0, while the ratio of phosphate groups of OMP to basic groups of globulin is only 8.0. The maximum binding of both anions at the precipitation point amounts to 0.8 mol phosphate per mol basic groups of albumin with both polyanions at pH 3.0 using turbidimetry. An excess binding of polyanions to the globulin has been found with phytic acid at pH < 3.0 and with OMP at pH 3.0 after increasing the amount of OMP over the precipitation point.     

Effect of Phytic Acid on the In-Vitro Rate of Digestibility of Rapeseed Protein and Amino Acids

Phytic acid in rapeseed flour was reduced by pH adjustment to 5.15 with subsequent dialysis or by phytase treatment at pH 5.15 with subsequent dialysis. The effect of phytate reduction on the rate and extent of protein and amino acid digestibilities was then determined using an in vitro pepsin-pancreatin proteolysis method with simultaneous dialysis of reaction products. A 51% reduction in phytic acid increased the rate of release of many essential amino acids but a further 89% reduction in phytic acid did not enhance that effect. Phytate removal did not improve the protein digestibility.     

双低油菜籽资源综合开发产业化

双低油菜籽作为一种新的油料资源，具有广阔的应用前景。分析测定了双低油菜籽主要成分及蛋白质、植酸、硫甙和单宁的溶解度，并与普通油菜籽的组成成分进行了比较。着重论述了双低油菜籽综合开发产业化的几种主要途径：油菜籽脱皮、挤压膨化(低温压榨)、浸出制油新工艺；菜籽浓缩蛋白的制备；天然复合氨基酸粉的制备；菜籽皮壳的利用以及生物柴油的生产。     

油菜籽加工技术研究进展

油菜籽是世界第三大油料,我国油菜籽种植面积和总产居世界首位。油菜籽是食用、饲用和能源用的重要原料,目前世界各国对油菜籽的高效加工利用技术均展开了广泛的研究。简要介绍了油菜籽脱皮冷榨膨化工艺技术,无有机溶剂油脂高效提取工艺技术,菜籽饼粕同步提取多酚、多糖、植酸和浓缩蛋白工艺技术,Burco食用菜籽蛋白制备技术等目前油菜籽加工技术研究的最新成果。     

菜籽饼粕脱毒工艺参数的研究

以菜籽饼粕为研究对象，采用硫酸甲醇溶液为脱毒体系，确定了该法脱毒的最佳工艺参数：硫酸：甲醇：水=4％：90％：6％(体积比)的混合液为脱毒体系，与菜籽饼粕的混合比为8：1(mL／g)，室温下浸提30min。植酸提取率近90％，单宁提取率和硫代葡萄糖甙(简称硫甙)的去除率均超过80％，粕中硫甙的含量可降到2mg/g以下，满足饲料标准的要求；也达到了同时提取植酸和单宁的目的。     

Inositol phosphate content and trypsin inhibitor activity in ready-to-eat cruciferous sprouts

Four cruciferous seeds (small radish, radish, white mustard and rapeseed) were germinated in order to study the fate of inositol hexaphosphate (IP-6, phytic acid) and activity of trypsin inhibitor (TIA). Reduction in the content of phytic acid depended on the time of germination. After four days of germination, when sprouts were ready-to-eat, the amount of this compound was about 50% lower in three out of the four seeds evaluated. Next, a sharp reduction in phytic acid occurred during thermal treatments (pasteurization and sterilization) of germinated rapeseed and radish sprouts. In thermal processes, a decrease in inositol hexaphosphate content was accompanied by the appearance of lower forms of inositol phosphates: IP-5, IP-4 and IP-3.The analysis of TIA, in rapeseed and radish seeds, in four-day sprouts and in these sprouts after thermal treatment, showed that only thermal processes caused complete disappearance this activity.     

菜籽清蛋白的主要成分分析及急性毒性试验研究

为了探讨菜籽清蛋白作为食品添加剂和蛋白强化剂的可能性,对从菜籽粕中提取的菜籽清蛋白进行主要成分分析和急性毒性试验。结果表明:相比于菜籽粕,超声辅助提取的菜籽清蛋白中的抗营养因子植酸、单宁和硫甙含量明显降低,蛋白质含量大幅提高,水分、灰分和粗脂肪含量有所降低;急性毒性试验结果初步表明菜籽清蛋白无毒,可考虑将其作为蛋白添加剂或营养强化剂应用于食品工业中。     

复合法提取高温菜籽粕中蛋白质的研究

以高温菜籽粕为原料,研究了淀粉酶法与碱提法结合提取蛋白质的工艺,其优化条件为:酶解pH7.0,酶解温度50℃,料液比1∶20,加酶量2.5%,酶解时间3 h;碱提pH10.0,碱提温度55℃,碱提时间2 h,料液比1∶12。在此条件下,菜籽蛋白质提取率达到71.63%。经等电点沉淀、70%乙醇脱色及冷冻干燥后,产品呈浅灰色,菜籽蛋白质得率为9.3%,单宁脱除率为56.65%,植酸脱除率为62.77%,硫甙脱除率达93.66%。     

发酵法降解油菜籽废水中植酸的工艺研究

水酶法提取菜籽油工艺产生了大量废水,其中含有丰富的水溶性蛋白、碳水化合物和抗营养因子。为了降解水中的抗营养物质植酸,利用筛选出的酵母菌对其进行发酵,并通过正交试验优化培养条件,得出K酵母在32℃,pH 7条件下培养36 h,可将废水中植酸降解87%,从而为废水的循环利用或达标排放打下了基础。     

菜籽粕脱毒提取菜籽蛋白研究进展：Ⅱ菜籽分离蛋白的制取

比较了不同萃取水相、菜籽品种及菜籽加工方法对蛋白质萃取率的影响。介绍了几种具有较高蛋白质得率的菜籽分离蛋白制取工艺，并对降低分离蛋白产品植酸含量进行了讨论。     

Effect of Germination on Phytic Acid, Protein and Fat Content of Rapeseed

Rapeseed was germinated over a 7-day period and the changes in phytic acid, protein and fat contents were monitored. Two-day germination period reduced the phytic acid by 13% and slightly increased the fat and protein by 6 and 4%, respectively. A 65% decrease in phytic acid, 10% increase in protein and 46% decrease in fat were observed after 7 days of germination. The free fatty acid values increased from 1 to 120. While reduction in phytic acid and increase in protein are desirable, the reduction in fat and its increased hydrolysis to free fatty acids after 7 days may be considered detrimental if rapeseed oil is to be extracted for commercial purposes.