微生物固态发酵菜籽粕营养特性的研究

以普通菜籽粕为原料,选用枯草芽孢杆菌、地衣芽孢杆菌、植物乳杆菌、啤酒酵母、季也蒙毕赤酵母及黑曲霉等菌种,通过单菌株与混菌株发酵试验,研究发酵对菜籽粕中粗蛋白和抗营养因子含量的影响。结果表明,芽孢杆菌的蛋白酶活性高于其他菌株;混菌株发酵效果明显优于单菌株发酵;混菌株发酵中枯草芽孢杆菌、植物乳杆菌和啤酒酵母三菌种组合发酵能较好地提高菜籽粕作为饲料蛋白的品质,此时其粗蛋白质增加率和硫代葡萄糖苷(硫苷)、唑烷硫酮(OZT)、单宁、植酸降解率分别为5.37、93.44、99.99、34.86、18.15%(干基)。     

菜籽粕中抗营养因子植酸酶解条件的研究

在菜籽粕中直接添加外源植酸酶,作用于菜籽粕,使其一种主要的抗营养因子(ANF)--植酸分解,根据影响酶反应的主要因素:温度、pH值、反应时间、酶浓度等进行单因素试验,选择合适的因素水平按L9(34)设计,通过正交试验对酶解条件进行了优化.结果表明:植酸酶酶解的优化条件为温度45℃、pH值4.7、反应时间90 min、酶浓度2.4%(菜籽粕量),植酸酶解率可达60%.     

微生物发酵法降解谷物中抗营养因子的研究进展

谷物是人及动物饮食中的重要组成部分,但除营养成分外,谷物中也含有多种抗营养因子,如胰蛋白酶抑制剂、植酸、非淀粉类多糖、凝集素和单宁等。抗营养因子不但影响谷物的消化吸收率,甚至会对生物体产生健康隐患。利用微生物发酵法可以有效降低谷物中抗营养因子的含量,提高谷物的营养价值。目前,在谷物中抗营养因子研究的基础上,该文对利用微生物发酵法降解抗营养因子的发酵工艺以及微生物发酵法降解各类谷物抗营养因子的研究进展进行了概述。     

稻米中抗营养因子的研究进展

植酸是稻米的天然组分，是稻谷种子生长和活动所必需的。在稻谷的生长过程中，不仅对灌浆十分有利，而且对稻谷成分的形成和工艺品质也有很大的促进作用，但是对人类营养而言，植酸是一种抗营养物质，植酸可与钙、锌、铁等物质螯合，降低钙、锌、铁等的生理利用率；植酸还能与蛋白质等形成不溶性复合物，降低氨基酸的利用率；一些消化酶的作用也受到植酸的抑制，从而影响到蛋白质、淀粉、脂肪的利用率。     

粗壮脉纹孢菌固态发酵对菜籽粕营养品质的改善

粗壮脉纹孢菌是一种高产纤维素酶和类胡萝卜素的优良菌株。以粗壮脉纹孢菌固态发酵菜籽粕为对象,研究菜籽粕在发酵过程中蛋白质等营养成分、抗营养因子含量的变化。研究结果表明,随着发酵时间的延长,96 h后粗蛋白含量、可溶性蛋白含量、总氨基酸含量极显著增加(P<0.01),分别提高12.50%,232.52%,724.45%,类胡萝卜素含量由0μg/100 g增加到(64.68±1.42)μg/100g,酸溶性蛋白含量先上升后下降至平稳,24 h达到最高值(25.86±0.05) g/100 g,粗纤维含量、单宁、植酸、硫甙整体呈显著(P<0.05)下降趋势,降解率分别为23.48%,24.98%,10.20%,14.79%。粗壮脉纹孢菌固态发酵菜籽粕可大大改善菜籽粕的营养价值。     

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.     

多菌种固态发酵去除菜籽粕中的植酸

以普通菜籽粕为原料,选用枯草芽孢杆菌、蜡样芽孢杆菌、植物乳酸菌及酪酸梭状芽孢杆菌多个菌种,通过单菌与混菌发酵,研究发酵对菜籽粕中植酸含量的影响.结果表明,单菌发酵中枯草芽孢杆菌对植酸降解效果优于其他菌种,其降解率可达62.4%;混菌发酵效果优于单菌发酵,当混菌接种量分别为枯草芽孢杆菌6%,蜡样芽孢杆菌4%,植物乳酸菌6%,水料比为1.3:1,pH 6.9,30℃发酵48 h时,菜籽粕植酸含量从2.26%(干基)降至0.221%(干基),降解率达90.15%,粗蛋白含量提高5.19%(干基).     

蚕豆中抗营养因子的研究

对蚕豆中所含的一些对人体有害的物质(抗营养因子)进行了总结分析。并介绍了一些常用的方法来降低蚕豆抗营养因子对人体健康造成的不利影响。     

大豆中营养因子和抗营养因子研究进展

大豆中含有抗营养因子和营养因子,营养因子包括大豆磷脂、大豆异黄酮等,抗营养因子包括蛋白酶抑制因子、抗原蛋白、凝集素、植酸等,大豆低聚糖和皂甙具有营养和抗营养双重作用。对大豆中的营养因子和抗营养因子的生理功能,对动物的营养及危害作用进行了论述。     

微生物发酵生产高蛋白多肽菜籽粕的研究

以菜籽粕为原料,以菜籽粕粗蛋白质含量和多肽含量为评价指标,通过植物乳酸菌、黑曲霉菌、枯草芽孢杆菌的单菌发酵和混菌发酵实验,进行最佳菌种组合和发酵条件的研究。结果表明:单菌发酵黑曲霉菌效果最好,菜籽粕粗蛋白质含量和多肽含量分别为38.4%和3.682%;混菌发酵最佳菌种组合为植物乳酸菌、黑曲霉菌、枯草芽孢杆菌,其接种量分别为4%、6%、6%,优化发酵条件为水料比1.7∶1、34℃下发酵48 h。在上述条件下菜籽粕粗蛋白质含量和多肽含量分别为42.5%和7.86%,硫甙含量降至21.637μmol/g、植酸含量为0.27%、单宁含量为0.41 mg/g,得到高蛋白、多肽、低毒的菜籽粕饲料。     

Microbiological degradation of glucosinolates in defatted rapeseed meal

During the degradation of thioglucosides in defatted rape seed meal (RES) microorganisms were found, whose ability to degrade glucosinolates (GSL) and vinyl thio-oxazolidone (VTO) was not known so far. The isolated microorganisms are two strains of bacteria of the species Bacillus cereus and the yeast Trichosporon cutaneum. The degradation of GSL and VTO in the cultural broths by the Bacillus cereus strains was the more complete the more other Gram-negative bacteria from RES were additionally present. Drinking tests with Wistar rats showed that here is a relation between the watersoluble and mainly bitter toxin substances of rape and their influence on the increase of the animals body weight.     

菜籽饼粕中硫甙降解产物定量检测方法研究进展

对菜籽饼粕中硫甙降解产物的定量测定方法进行了归纳总结.测定异硫氰酸酯主要有重量法、容量法、碘量法、氧化还原法和色谱法;测定嗯唑烷硫酮主要有紫外分光光度计法和液相色谱(HPLC)法;测定硫氰酸酯主要有分光光度法、气(液)相色谱法及红外法;测定腈类主要有气相色谱法、化学定氮法及红外法.可根据要求和目的,并结合实际具备的仪器、试剂等,选择最合适的分析方法.     

菜籽饼粕中硫代葡萄糖甙测定方法的探讨

通过单因素试验、正交实验等分析方法探讨了紫外分光光度法测定菜籽粕中硫甙含量的各个因素条件,实验结果表明,方法的最佳酶解反应条件为:酶量:样品量=2:10,缓冲溶液的pH=7,温度30℃,时间2h;最佳显色反应条件为:氨水-乙醇浓度为20%,温度50℃,时间2 h;检出限范围1.4～280 μmol/g,精密度实验的变异系数为0.39%.     

菜籽饼粕中硫甙及其降解物分析中存在的问题

阐述了菜籽饼粕中硫甙的降解途径和各种毒素的存在形式,并指出目前分析测定硫甙、噁唑烷硫酮、异硫氰酸酯、腈类和硫氰酸酯等毒素中存在的一些问题,以期为今后的研究提供参考。     

Determination of phytic acid in rapeseed meal

A new method has been developed for the determination of phytic acid in rapeseed meal based on extraction of the phytate with 15% trichloroacetic acid. After enzymatic hydrolysis with phytase from wheat, the phosphate is determined spectrophotometrically. The method has been applied to a number of varieties of rapeseed. The variation within a variety was nearly as high as within a population of varieties of the same species. The results imply that the phytic acid content of rapeseed is mostly influenced by environmental factors such as the availability of phosphorus in the soil.     

菜籽粕芥子碱的研究概况

芥子碱是十字花科植物中重要的次生代谢产物,油菜籽是含有芥子碱的唯一的大宗作物。芥子碱是菜籽粕中存在的最重要的简单酚类物质,其存在影响菜籽粕的适口性、蛋白质的消化吸收率并使鸡蛋产生鱼腥味。通过对芥子碱的存在形式、合成途径、性质、提取纯化方法、在油菜籽和菜籽粕酚类物质中的地位、对菜籽粕营养的影响及其在物理化学及酶作用下的降解研究进展进行综述,以期为菜籽粕芥子碱的降低寻找适宜的途径。     

菜籽粕后脱皮工艺研究

以预榨浸出后的菜籽粕为原料,通过对菜籽粕粉碎、筛分及风选,将菜籽粕中的皮进行分离,以提高菜籽粕中的蛋白含量,对其中影响较大的筛孔目数进行了选择与确定,试验得出:粉碎菜籽粕过40目筛时筛下物经风选得到的产品蛋白含量较高,为44%;此条件下产品总得率为28.3%。得到的菜籽粕可作为进一步生产菜籽浓缩蛋白的原料。     

Indoleacetonitriles—thermal degradation products of indole glucosinolates in commercial rapeseed (Brassica napus) meal

Commercial low-glucosinolate rapeseed (Brassica napus L) meal (LG RSM) was extracted with dichloromethane and subjected to chromatography on Sephadex LH-20 to isolate indole-containing compounds which were detected using TLC. Thin layer chromatography of dichloromethane extracts of various heat-treated preparations of defatted low-glucosinolate rapeseed cv Westar was also used to establish the origin of the major indole derivative. One of the minor components was identified as 3-indoleacetonitrile (IAN) based on comparisons of GLC retention times and mass spectral data with authentic IAN. The major indole derivative was identified as 4-hydroxy-3-indoleacetonitrile by comparison of mass spectral data with that for IAN and by establishing its precursor as 4-hydroxy-3-indolylmethylglucosinolate.     

Influence of glucosinolates and high-molecular factors on the nutritional value of low-glucosinolate rapeseed meal

In order to ascertain the reason for the prominent growth-inhibiting effect of unheated low-glucosinolate rapeseed meal, the nutritional value of various fractions of the meal was evaluated in growth experiments using mice. A meal containing myrosinase activity was not growth-inhibiting after the low-molecular compounds had been removed by dialysis. A hydrolysis of glucosinolates to isothiocyanates and oxazolidinethiones would probably not explain the marked antinutritional properties of the low-molecular fraction. Heat treatment after autolysis did not improve the nutritional value of the meal. The harmful factors present in an autolysed meal could be extracted with methylene chloride. This extract contained nitriles, but no isothiocyanates or oxazolidinethiones. Thus, together with other information, the results suggest that the growth-inhibiting effect of unheated, low-glucosinolate rapeseed meal is mainly due to the presence of factors that direct the hydrolysis of glucosinolates towards nitrile production.     

菜籽粕贮藏条件的探讨

针对菜籽粕的生理特性,阐述菜籽粕水分含量、粗灰分含量、粕温及环境温湿度对菜籽粕贮藏期间质量的影响。结果表明,菜籽粕水分含量≤12%,灰分含量≤8.5%,入库粕温≤40℃,库内温度≤40℃、相对湿度≤70%,可确保菜籽粕的安全贮藏。