膜分离在氨基酸清洁生产中的应用

本文简要介绍了膜设备的种类、作用机理，并阐述了膜分离在氨基酸行业中的应用。膜分离技术的广泛应用为氨基酸行业实施清洁生产奠定了坚实的技术基础。     

膜分离技术在氨基酸生产上的应用

本文简述了膜分离技术特征和性能，阐述了国内外膜分离技术在氨基酸工业上的应用情况，介绍了其处理工艺和运行结果，通过经济效益分析，表明采用膜分离技术因其高效、节能，应用于氨基酸生产的部分工艺中，能达到环境效益与经济效益的统一。     

膜分离技术在食品工业中的应用

一、前言 膜分离技术是一门新兴科学,起步较晚,在国外已进行了系统研究,并在许多领域得到广泛的应用。我国虽然开展这项研究较晚,但也取得可喜的进展,在一些行业已应用于工业生产。 膜分离起初应用在水的净化,海水淡化等方面,由于膜分离技术的发展及其许多优越性,膜分离技术现已广泛应用于化工、食品、轻纺、能源、环保等行业。 1965年膜分离技术已在食品中开始应用,乳品加工在1983年已用于工业化生产。膜分离技术在食品工业中的应用具有以下优点:     

膜分离技术用于印染废水处理及回用的研究进展

印染行业的废水量大、水质复杂、对环境影响大,是工业污水处理的重要部分。近年来,随着污水处理行业膜技术的应用越来越广泛,印染废水采用膜分离技术也逐渐增多,其出水能满足回用要求,有效地缓解了用水量,节约了水资源。综述了不同膜分离技术在印染废水中的应用进展,指出了膜分离技术处理印染废水的优势及其存在的问题。     

超滤与反渗透技术在造纸工业的应用进展

膜分离技术现今已经成熟地应用在食品、高分子材料、化工、环境、皮革、制药等各个行业,在造纸中的应用也越来越多。文章介绍了膜分离技术中超滤和反渗透技术在造纸过程的白水回收、黑液分离、脱墨浆废水及外排水回收几个方面的应用,给出一些国内外造纸厂膜技术处理造纸废水的实例,对膜技术在造纸行业的应用前景作出展望。     

膜分离技术及其在农产品加工中的应用分析

正膜分离技术有其显著的技术应用有效性,本文主要分析超滤(UF)膜技术、微滤(MF)膜技术、反渗透(RO)膜技术,重点介绍膜分离技术在牛初乳加工和果汁加工中的应用,以期提高其技术应用有效性。常见的膜分离技术超滤(UF)膜技术超滤分离技术目前是膜分离技术中应用最广泛的一种分离手段。在国外,超滤膜分离技术在农产品加工行业已成功地应用在植物蛋白的分离、果汁的澄清、蔬菜汁的浓缩、酶精制、发酵液和菌体的浓缩及乳制品等方面。微滤(MF)膜技术     

高新技术在油脂行业中的应用

论述了一些高新技术在油脂行业中的应用，如膜分离技术、超临界CO2萃取、生物技术等。     

专家发现氨基酸混合物高效分离新方法

近日,中国农业科学院麻类研究所麻纤维产品与加工技术团队在聚离子液体膜分离氨基酸混合物研究方面取得重要进展。研究发现,聚离子液体膜具有良好的机械性能,对氨基酸的分离效果好且具有优良的抗菌性和抗污染性,该研究为氨基酸混合物分离工业应用提供了新方法。相关研究成果在线发表在《Journal of Colloid and Interface Science(胶体与界面科学)》上。据谭志坚研究员介绍,氨基酸被广泛应用于食品、饲料和医药等领域,蛋白质水解和微生物发酵是获得氨基酸的最常用的方法,但是往往获得的是氨基酸混合物。膜分离方法是分离氨基酸混合物的一种重要手段,聚离子液体膜与其他膜相比.     

杏鲍菇酶解液膜分离脱苦工艺的研究

研究膜分离技术对杏鲍菇酶解液的脱苦工艺。在单因素实验的基础上,采用响应面实验设计优化得到500u纳滤膜分离脱苦的最优条件为压力0.67MPa、pH7.81、温度45.0℃,脱苦后滤液中氨基态氮透过率为82.6%,滤液苦味评分为1.8分;对膜分离脱苦前后酶解液中基本营养组成含量进行对比分析,经膜分离脱苦处理后的杏鲍菇酶解液中氨基酸总量、鸟苷酸和肌苷酸的保留率分别为82.6%、79.9%和75.2%。结果表明,酶解液经膜分离脱苦后,氨基酸和核苷酸的保留率均较高,脱苦效果良好,说明膜分离技术可应用于蛋白质酶解液的脱苦。     

膜分离技术及其在食品工业中的应用

主要介绍了膜分离技术的发展现状及其应用在食品工业与传统工艺相比的优点、各种膜分离过程的定义和基本原理、膜组件的结构及应用特性、膜分离技术的选择及系统的方案设计、在食品工业中的应用实例以及新的膜分离技术在食品工业中应用前景、展望等。通过与传统工艺的比较和分析,许多应用实例表明,膜分离技术在工业中的应用改变了食品工业传统落后的生产工艺,节省了能源,提高了产品质量,有着极为广阔的应用发展前景。     

谷氨酸棒状杆菌高效发酵谷氨酸的关键分子机理研究进展

谷氨酸是世界上产量最大的氨基酸,在食品、医药、工农业等领域具有广泛的用途。谷氨酸棒状杆菌是工业生产谷氨酸的主要菌株,从发现谷氨酸棒状杆菌以来,国内外在谷氨酸过量产生机理方面的研究已取得了一定的科研成果。本文就发酵过程中基因转录水平、关键酶酶活、细胞膜与运输蛋白的结构3个层面机理的研究进展做一综述。最后对谷氨酸过量产生的机理进行分析,将来需从生理作用及调控因子等方面研究,进一步完善谷氨酸过量产生机理,以期对提高谷氨酸产量以及开发微生物合成其他生物产品提供参考和方向。     

Electrodialytic Phenomena and Their Applications in the Dairy Industry: A Review

Electrodialysis (ED) is an electrochemical separation process by which electrically-charged species are transported from one solution to another. ED is a combined method of dialysis and electrolysis and can be performed with two main cell types: multi-membrane cells for dilution-concentration and water dissociation applications (membrane phenomena), and electrolysis cells for redox reactions (electrode phenomena). The dilution-concentration principle applications in the dairy industry consist mainly of the demineralization of milk or milk by-products. The use of ED with monopolar membrane for protein separation and acid caseinate production, and in bioreactors for organic acid production, is also studied in the dairy industry. The interest of ED as a membrane process has been triggered recently by the development of a new membrane type, bipolar membrane. This membrane carries out the dissociation of water molecules. ED with bipolar membranes was applied very recently to the production of lactic acid from whey product fermentation, production of caseinates, and fractionation of whey proteins. Two principle applications of electrode reactions were published: electrochemical coagulation (EC) to precipitate milk proteins, and electroreduction for the reduction of disulfide bonds in the proteins. It appears in this article that processes using membrane phenomena are more numerous and developed than electrolytic applications. This is the composition of milk and the lack of knowledge of redox reactions of the different food compounds that limit the applications and the development of electrolytic phenomena. Electrodialytic phenomena present a great potential for application in the dairy industry, and more generally, in the food industry; many of these applications have to be discovered.     

Electrodialytic phenomena and their applications in the dairy industry: a review

Electrodialysis (ED) is an electrochemical separation process by which electrically-charged species are transportedfrom one solution to another ED is a combined method of dialysis and electrolysis and can be performed with two main cell types: multi-membrane cells for dilution-concentration and water dissociation applications (membrane phenomena), and electrolysis cells for redox reactions (electrode phenomena). The dilution-concentration principle applications in the dairy industry consist mainly of the demineralization of milk or milk by-products. The use of ED with monopolar membrane for protein separation and acid caseinate production, and in bioreactors for organic acid production, is also studied in the dairy industry. The interest of ED as a membrane process has been triggered recently by the development of a new membrane type, bipolar membrane. This membrane carries out the dissociation of water molecules. ED with bipolar membranes was applied very recently to the production of lactic acid from whey product fermentation, production of caseinates, and fractionation of whey proteins. Two principle applications of electrode reactions were published: electrochemical coagulation (EC) to precipitate milk proteins, and electroreduction for the reduction of disulfide bonds in the proteins. It appears in this article that processes using membrane phenomena are more numerous and developed than electrolytic applications. This is the composition of milk and the lack of knowledge of redox reactions of the different food compounds that limit the applications and the development of electrolytic phenomena. Electrodialytic phenomena present a great potential for application in the dairy industry, and more generally, in the food industry; many of these applications have to be discovered.     

Electrodialytic phenomena and their applications in the dairy industry: a review

Electrodialysis (ED) is an electrochemical separation process by which electrically-charged species are transported from one solution to another ED is a combined method of dialysis and electrolysis and can be performed with two main cell types: multi-membrane cells for dilution-concentration and water dissociation applications (membrane phenomena), and electrolysis cells for redox reactions (electrode phenomena). The dilution-concentration principle applications in the dairy industry consist mainly of the demineralization of milk or milk by-products. The use of ED with monopolar membrane for protein separation and acid caseinate production, and in bioreactors for organic acid production, is also studied in the dairy industry. The interest of ED as a membrane process has been triggered recently by the development of a new membrane type, bipolar membrane. This membrane carries out the dissociation of water molecules. ED with bipolar membranes was applied very recently to the production of lactic acid from whey product fermentation, production of caseinates, and fractionation of whey proteins. Two principle applications of electrode reactions were published: electrochemical coagulation (EC) to precipitate milk proteins, and electroreduction for the reduction of disulfide bonds in the proteins. It appears in this article that processes using membrane phenomena are more numerous and developed than electrolytic applications. This is the composition of milk and the lack of knowledge of redox reactions of the different food compounds that limit the applications and the development of electrolytic phenomena. Electrodialytic phenomena present a great potential for application in the dairy industry, and more generally, in the food industry; many of these applications have to be discovered.     

Bioutilisation of whey for lactic acid production

The disposal of whey, the liquid remaining after the separation of milk fat and casein from whole milk, is a major problem for the dairy industry, which demands simple and economical solutions. The bioconversion of lactose present in whey to valuable products has been actively explored. Since whey and whey permeates contain significant quantities of lactose, an interesting way to upgrade this effluent could be as a substrate for fermentation. Production of lactic acid through lactic acid bacteria could be a processing route for whey lactose and various attempts have been made in this direction. Immobilised cell technology has also been applied to whey fermentation processes, to improve the economics of the process. A fermentative means of lactic acid production has advantages over chemical synthesis, as desirable optically pure lactic acid could be produced, and the demand for optically pure lactic acid has increased considerably because of its use in the production of poly(lactic acid), a biodegradable polymer, and other industrial applications. This review focuses on the various biotechnological techniques that have used whey for the production of lactic acid.     

膜分离技术在食品精深加工中的应用

膜分离技术已在食品加工业中得到广泛应用,并推动食品精深加工业的快速发展。膜分离技术的理化稳定性、分离高效性、环境友好性以及经济实用性决定了其广阔的应用前景。本文按照食品生产种类,综述膜分离技术在食品精深加工中的应用。     

Application of Plackett–Burman experimental design for investigating the effect of wort amino acids on flavour‐active compounds production during lager yeast fermentation

Aroma‐active higher alcohols and esters are produced intracellularly in the cytosol by fermenting lager yeast cells, which are of major industrial interest because they determine aroma and taste characteristics of the fermented beer. Wort amino acid composition and their utilization by yeast during brewer's wort fermentation influence both the yeast fermentation performance and the flavour profile of the finished product. To better understand the relationship between the yeast cell and wort amino acid composition, Plackett–Burman screening design was applied to measure the changes in nitrogen composition associated with yeast amino acids uptake and flavour formation during fermentation. Here, using an industrial lager brewing strain of Saccharomyces pastorianus , we investigated the effect of amino acid composition on the accumulation of higher alcohols and volatile esters. The objective of this study was to identify the significant amino acids involved in the flavour production during beer fermentation. Our results showed that even though different flavour substances were produced with different amino acid composition in the fermentation experiments, the discrepancies were not related to the total amount of amino acids in the synthetic medium. The most significant effect on higher alcohol production was exercised by the content of glutamic acid, aromatic amino acids and branch chain amino acids. Leucine, valine, glutamic acid, phenylalanine, serine and lysine were identified as important determinants for the formation of esters. The future applications of this information could drastically improve the current regime of selecting malt and adjunct or their formula with desired amino acids in wort. Copyright © 2017 The Institute of Brewing & Distilling     

Apple Aminoacid Profile and Yeast Strains in the Formation of Fusel Alcohols and Esters in Cider Production

The amino acid profile in dessert apple must and its effect on the synthesis of fusel alcohols and esters in cider were established by instrumental analysis. The amino acid profile was performed in nine apple musts. Two apple musts with high (>150 mg/L) and low (<75 mg/L) nitrogen content, and four enological yeast strains, were used in cider fermentation. The aspartic acid, asparagine and glutamic acid amino acids were the majority in all the apple juices, representing 57.10% to 81.95%. These three amino acids provided a high consumption (>90%) during fermentation in all the ciders. Principal component analysis (PCA) explained 81.42% of data variability and the separation of three groups for the analyzed samples was verified. The ciders manufactured with low nitrogen content showed sluggish fermentation and around 50% less content of volatile compounds (independent of the yeast strain used), which were mainly 3‐methyl‐1‐butanol (isoamyl alcohol) and esters. However, in the presence of amino acids (asparagine, aspartic acid, glutamic acid and alanine) there was a greater differentiation between the yeasts in the production of fusel alcohols and ethyl esters. High contents of these aminoacids in dessert apple musts are essential for the production of fusel alcohols and most of esters by aromatic yeasts during cider fermentation.     

蛹虫草菌丝体发酵培养过程中氨基酸添加技术研究

组氨酸、精氨酸、赖氨酸是对蛹虫草生长影响较大的3 种碱性氨基酸,本实验研究在蛹虫草液体发酵过程中添加上述氨基酸的不同条件对蛹虫草菌丝体生物量和其中主要抗癌功能成分虫草素的影响。首先进行添加氨基酸种类、氨基酸的添加量、初始pH 值、培养温度对蛹虫草菌丝体生物量和虫草素含量的单因素试验,在此基础上进行四因素三水平的正交试验。结果表明：对蛹虫草菌丝体生物量影响从大到小的顺序依次是：氨基酸种类＞培养温度＞初始pH 值＞氨基酸添加量。增加蛹虫草菌丝体生物量的最佳培养条件为：添加氨基酸种类为精氨酸,培养温度为26℃,培养初始pH 值为6,100mL PDA 发酵培养液添加精氨酸0.3g。对蛹虫草菌丝体中虫草素含量影响从大到小的顺序依次是：氨基酸种类＞初始pH 值＞培养温度＞氨基酸添加量。增加菌丝体中虫草素含量的最佳培养条件是添加氨基酸种类为精氨酸,培养温度为24℃,100mL PDA 发酵培养液添加0.3g,培养的初始pH 值为6 。     

不同中和剂对米根霉发酵产L- 乳酸的影响

在米根霉发酵产L- 乳酸过程中,采用CaCO3 作为中和剂会造成下游分离过程中膜堵塞和环保压力,因此以NH3·H2O 和NaOH 替代CaCO3 作中和剂,对米根霉发酵产L- 乳酸的工艺条件和发酵动力学进行研究。结果表明：添加CaCO3 后L- 乳酸产量平均提高7.3 倍;NaOH、NH3·H2O 作为中和剂的最佳浓度及质量分数分别为10mol/L、25%,以该条件进行发酵72h 得菌丝体小球直径分别为0.2～1.2mm 和1.2～2.2mm,残糖含量分别为2.58g/L 和1.37g/L,L- 乳酸产量分别为74.34g/L 和80.61g/L。