米曲霉固态发酵大豆粕制备大豆肽研究

对米曲霉固态发酵大豆粕生产大豆肽条件进行研究,结果表明,最适发酵原料(由大豆粕和麸皮组成)中大豆粕含量为93%。发酵温度35℃,初始pH为6.8,发酵时间102 h;在此条件下,发酵得到大豆肽转化率达62.77%。     

米曲霉固态发酵豆粕制备大豆肽的研究

对米曲霉固态发酵豆粕生产大豆肽的条件进行了研究。结果表明,最适的发酵原料（由豆粕和麸皮组成）中豆粕含量为93％,发酵温度35℃,初始pH值为6．8,发酵时间102h。在此条件下,发酵得到的大豆肽转化率达62．77％。     

温度变化对固态发酵豆粕产大豆肽工艺影响的研究

以豆粕为原料,通过米曲霉的固态发酵生产大豆肽。依据发酵豆粕过程中所产蛋白酶的最适温度以及豆粕最适水解温度,对大豆肽生产工艺进行优化,研究温度变化对固态发酵豆粕产大豆肽工艺的影响。     

发酵豆粕制备大豆肽饮料发酵条件的研究

文中对米曲霉液态发酵豆粕制备大豆肽发酵液进行了研究.以发酵液中大豆肽转化率为指标,研究豆粕浓度、碳氮比(C/N)、发酵温度和发酵时间对其影响.正交试验确定最佳的发酵条件,即豆粕浓度为3％、C/N为14、发酵温度为30℃、发酵时间为46h,得到的大豆肽发酵液大豆肽转化率达到55.6％.所得的大豆肽分子量分布在204u～1335u之间的百分比为43.28％.     

米曲霉固态发酵豆粕生产大豆肽

采用米曲霉A-9005固态发酵豆粕,研究所产蛋白酶的活力。结果表明其较优工艺为：发酵原料中豆粕含量为87%,初始pH值6.4,发酵温度为33℃,发酵时间为102 h,测得蛋白酶活为1 789.47 U/g。试验为米曲霉固态发酵豆粕产大豆肽的研究提供了相应的工艺参数和一定的理论依据。     

固态发酵法生产发酵豆粕的研究

采用米曲霉(A3.042)和啤酒酵母混合菌株固态发酵法生产发酵豆粕,利用霉菌产生的多种酶系,降解其中的纤维素及蛋白质等物质,利用酵母菌合成菌体蛋白。研究了发酵料坯组成、接种菌配比、接种量及发酵温度对发酵豆粕中蛋白质含量的影响,得到了最佳工艺条件:即最适温度28℃,发酵料坯组成100∶6(豆粕/麸皮),接种菌配比为1∶3(米曲霉/酵母),接种量6%,发酵时间为72h。发酵豆粕中粗蛋白含量可达49.10%,比原料中增加12.1%。     

混合菌种固态发酵法发酵豆粕生产大豆肽的研究

大豆肽是由大豆蛋白经水解所得到的由3～6个氨基酸残基组成的低分子肽混合物,分子量以低于1000Da的为主。以豆粕为原料,采用黑曲霉、米曲霉混合菌种固态发酵法生产大豆肽,制得的大豆肽具有较好的理化特性和生理活性,克服了酶解法产品苦味大和口感差等缺点,在很多领域得到了广泛应用。     

双菌种固态发酵豆粕生产大豆肽的研究

大豆肽是由大豆蛋白经水解所得到的由3～6个氨基酸残基组成的低分子肽混合物,分子量以低于1 000 Da的为主。以豆粕为原料,采用黑曲霉、米曲霉混合菌种固态发酵法生产大豆肽,制得的大豆肽具有较好的理化特性和生理活性,能去除抗营养因子,生产成本低,克服了酶解法产品苦味大和口感差等缺点。     

大豆玉米复配肽的固态发酵工艺优化

为了利用植物蛋白质资源和提高其营养价值,以豆粕和玉米蛋白粉为原料,应用枯草芽孢杆菌固态发酵制备大豆玉米复配肽。基于豆粕和玉米蛋白粉配比和发酵时间的考察与确定,研究了大豆玉米复配肽的固态发酵工艺条件,又考察了发酵温度、瓶装量、料液比及接种量对蛋白水解度和肽转化率的影响。应用4因素3水平响应面法对大豆玉米复配肽的固态发酵工艺进行优化研究,并分别建立了各因素与蛋白水解度和肽转化率的回归方程。结果表明,最佳固态发酵条件为:发酵温度40℃、瓶装量8.5 g、料液比1:1.2(g/m L)、接种量3.5%(m L/g),在此条件下,蛋白水解度为(32.73±0.17)%,肽转化率为(33.23±0.13)%,与理论预测值基本相符。因此,大豆玉米复配肽的固态发酵工艺是可行的,为大豆玉米复配肽的制备提供了科学依据。     

米曲霉固态发酵降解大豆致敏原条件的优化

为了最大程度地降低甚至消除米曲霉固态发酵豆粕产品的免疫反应性,此研究利用响应面法对米曲霉固态发酵豆粕降解大豆致敏原的条件进行了优化。首先对影响米曲霉固态发酵豆粕降解大豆致敏原的几个因素(发酵时间、接种量、发酵温度、培养基初始pH、料水比)进行了单因素研究,确定了对结果有较大影响的料水比、发酵温度和培养基初始pH这三个因素。其后利用Box-Behnken设计,确定了固态发酵的最佳条件,即当料水比为1:1.21(g/mL)、发酵温度29.8℃、pH为6.63时,得到理论最低致敏原降解率为99.15%。最后,经验证实验,最佳条件下实际平均致敏原降解率为99.02%。验证实验结果与理论值相差0.13%,说明该方程与实际情况拟合较好。     

固、液态发酵生产微生物脂肪酶

目前脂肪酶生产主要有固、液态两种发酵方法。该文对两种发酵方法进行详细对比,概述固、液态发酵生产脂肪酶菌种及发酵底物,并对分批、补料分批、连续发酵等技术进行对比;介绍数学模型在脂肪酶生产中应用,并展望利用酶工程技术和数学模型改良脂肪酶生产。     

微生物发酵法制备大豆多肽的研究

对微生物发酵方法制备大豆多肽的发酵条件进行研究,以脱脂豆粕为原料,在其发酵过程中通过对各种条件进行控制,选择出最佳的调控方案,通过比较各种调控因素如底物浓度、pH值、温度、发酵周期对肽转化率的影响,选择出转化率相对较高的最佳发酵条件:底物浓度为10%、最适pH值为7.0、最佳发酵温度为36℃、发酵周期为30 h,肽比率可达79.33%。     

Inhibition of malolactic fermentation by a peptide produced by Saccharomyces cerevisiae during alcoholic fermentation

The ability of Saccharomyces to inhibit Oenococcus oeni during the alcoholic fermentation by mechanisms other than SO(2) production was investigated. During fermentation in synthetic grape juice, S. cerevisiae strain RUBY.ferm inhibited the malolactic fermentation by O. oeni while strain EC1118 did not despite both strains producing similar amounts of SO(2). The bacterial inhibition exerted by RUBY.ferm was diminished when the wine was treated with proteases but not through the addition of nutrients. Wine fermented by RUBY.ferm was fractionated based on molecular weight and each fraction tested for the ability to inhibit the growth of O. oeni. The fraction containing compounds larger than 3 kDa was the sole inhibitory fraction. The inhibitory fraction was analyzed by SDS PAGE and showed a 5.9 kDa protein band present in wine fermented by RUBY.ferm that was not present in wine fermented by a non-antagonistic yeast, S. cerevisiae strain Saint Georges S101. The ability of the peptide to inhibit O. oeni seemed to be dependent on the presence of SO(2).     

Alcoholic fermentation by 'non-fermentative' yeasts

All type strains of 'non-fermentative' yeasts, available in the culture collection of the Centraalbureau voor Schimmelcultures, were reinvestigated for their capacity to ferment glucose in the classical Durham tube test. Although visible gas production was absent, nearly all strains produced significant amounts of ethanol under the test conditions. Under conditions of oxygen-limited growth, even strong alcoholic fermentation may occur in a number of yeasts hitherto considered as non-fermentative. Thus, shake-flask cultures of Hansenula nonfermentans and Candida silvae fermented more than half of the available sugar to ethanol. It is concluded that the taxonomic test for fermentation capacity, which relies on detection of gas formation in Durham tubes, is not reliable for a physiological classification of yeasts as fermentative and non-fermentative species.     

食用菌液体深层发酵的研究热点

利用液体深层发酵技术生产食用菌的菌丝体和生理活性物质一直是食用菌研究的热点之一。随着科学技术的不断发展,人们对食用菌在液体环境条件下菌丝体生长和产物产出的认识进一步深入,食用菌液体深层发酵的研究出现了许多新的热点。本文就液体发酵条件、液体深层发酵动力学、菌丝形态学等方面对食用菌液体深层发酵研究热点进行了阐述,并对其以后的研究发展趋势作出了展望。     

Sorghum fermentation followed by spectroscopic techniques

The effect of lactic bacteria fermentation on sorghum was followed by spectroscopic techniques (¹H NMR and FT-IR) and chemical analysis.

Wet-cooked sorghum flour was inoculated with lactic bacteria (Lactobacillus fermentum, Lactobacillus bulgaricus, Lactobacillus lactis, Pediococcus pentosaceus and Pediococcus cerevisiae) and a mixture of Lactobacillus bulgaricus and Streptococcus thermophilus from a commercial natural yogurt. Only L. fermentum and the commercial yogurt inoculum were able to grow in sorghum.

The induced lactic bacteria fermentations were compared with a spontaneous traditional fermentation carried out with flour used for fermentation purposes.

In all fermentations, a decrease in pH was noticed and consequently an increase in titratable acidity was detected. Also observed were an increase in free amino acids and total protein content. Reducing sugars, soluble protein and starch decreased during the fermentation processes. These chemical results were confirmed by ¹H NMR and FT-IR.

This study showed that spectroscopic methods are suitable and less time-consuming than chemical methods for following fermentation processes, giving the same relevant information and allowing large screening experiments.     

Nutritional improvement of cereals by fermentation

Cereal grains form a major source of dietary nutrients for all people, particularly those in the developing countries. However, compared with animal foods, nutritional quality of cereal grains is inferior due to lower protein content, deficiency of certain essential amino acids, lower protein and starch availabilities, and the presence of some antinutritional factors. Fermentation of cereals for a limited period of time improves amino acid composition and vitamin content, increases protein and starch availabilities, and lowers the levels of antinutrients. In this review, the available literature concerning the nutritional improvement of cereals by fermentation has been compiled and is critically analyzed. The traditional foods prepared by fermentation of cereals in different parts of the world are briefly described and future research needs to improve their nutritional contribution are addressed.     

发酵法制水溶性姜黄素

姜黄素是一种具有广泛生物活性以及医用价值的多酚类化合物,较差的水溶性和较低的生物利用度限制了其应用,糖苷化是提高其水溶性的有效手段。研究通过变色圈法筛选到1株产β-葡萄糖苷酶的益生菌,并对其进行菌落形态分析和16S r DNA测序,确定为玉米乳杆菌(Lactobacillus zeae strain OZK17)。该菌能够有效利用糖苷水解酶的逆反应对姜黄素分子进行糖基化修饰,形成姜黄素葡萄糖苷和姜黄素双葡萄糖苷,利用高效液相色谱(HPLC)和高效液相色谱-质谱联合(LC-MS)对糖苷化产物进行了确认。其中姜黄素葡萄糖苷转化率为40%,姜黄素双葡萄糖苷转化率为4%。     

纳豆激酶分批补料发酵的研究

在摇瓶和发酵罐上研究了分批补料发酵对枯草芽孢杆菌LSSE-22发酵生产纳豆激酶的影响。通过摇瓶分批发酵,确定最优碳源和氮源分别为葡萄糖和大豆蛋白胨。在优化初始葡萄糖和大豆蛋白胨浓度的基础上,进一步研究了补料底物、补料方式和补料时间对产酶的影响。结果表明,采用分批补糖发酵工艺,纳豆激酶产量可达到1 437.34 IU/m L,比分批培养提高了21.38%。在7.5 L发酵罐上进行分批补料发酵放大实验,纳豆激酶产量可达2 046.47 IU/m L,明显优于分批培养。     

大豆糖蜜发酵生产酒精的技术

介绍了大豆糖蜜生产酒精的工艺流程、生产控制和工艺参数。技术的应用拓宽酒精生产企业的原料来源,也为醇法大豆浓缩蛋白生产企业副产物利用提供了新的途径。