聚砜超滤膜在菜籽油脱胶中的应用

研究了聚砜超滤膜在菜籽油脱胶中的应用,讨论了操作时间(10 ～60 min),菜籽油-正己烷混合液中菜籽油质量分数( 10％～ 50％),操作压力(0.05～0.20 MPa)和操作温度(10～30℃)对脱胶效果的影响.结果表明:混合液渗透通量随操作时间的延长和混合液中菜籽油质量分数的提高而降低,但膜对磷脂的截留率表现出增大的趋势;渗透通量随操作压力和操作温度的升高而增大,但操作压力和操作温度对磷脂截留率影响很小.在实验条件下,聚砜超滤膜对30％菜籽油-正己烷混合液的渗透通量为8 ～33 kg/(m2 ·h),磷脂截留率为60％ ～ 80％:对菜籽油的渗透通量为0.2～3.5 kg/(m2·h),磷脂截留率达到91％ ～93％.     

无机陶瓷膜分离纯化大豆异黄酮的效果分析

用孔径为20、50 nm的无机陶瓷膜超滤低温豆粕乙醇萃取液,截留大豆蛋白,提高滤过液中大豆异黄酮的含量.试验表明,20 nm的膜超滤低温豆粕乙醇萃取液,其对大豆蛋白的截留率达75.52%,大豆异黄酮回收率达到84.85%;在60 ℃、0.15 MPa条件下,膜通量可达到130 L/(m2·h).超滤后,在60 ℃用0.5%NaClO 3.0%NaOH清洗,膜的水通量具有较好的恢复率.     

酸性染料废水纳滤处理的影响因素研究

为探讨酸性染料废水纳滤分离过程的影响因素、截留率和膜通量变化规律,选取常见的酸性大红染料,对染料模拟废水进行纳滤分离研究.结果表明:随操作压力的升高,染料截留率降低,盐截留率先升后降,膜通量增大;随着染料质量浓度的增加,膜通量降低,而染料截留率、盐截留率逐渐增加;pH=5~7时,染料的截留率达到最大,盐的截留率和膜通量呈下降趋势;染料的截留率、盐的截留率和膜通量随盐质量浓度的升高而降低;随运行时间的延长,膜通量先增加然后趋于稳定,染料和盐的截留率均有所下降.     

翘鳞伞胞外多糖无机陶瓷膜分离工艺研究

采用无机陶瓷膜分离提取翘鳞伞胞外多糖,考察不同孔径的膜对膜过滤的影响,优化膜通量影响因素,获得超滤膜分离最佳工艺条件.以微滤处理后的翘鳞伞发酵液为研究对象,测定了5种不同孔径超滤膜的膜通量以及多糖截留率;在5种陶瓷超滤膜中,截留分子量为50kDa的超滤膜最适合于翘鳞伞胞外多糖发酵液分离浓缩,当压力为0.1MPa～0.4MPa,温度为20℃～40℃时,压力和温度的提高均有利于超滤膜通量的增大:选择50kDa的超滤膜在0.3MPa、30℃的操作条件下,膜通量以及多糖截留率最佳.     

响应面法优化超滤提纯梅花鹿角盘多肽工艺

采用超滤法分离梅花鹿角盘多肽溶液,考察了超滤操作压力、操作时间和料液质量分数对膜渗透通量的影响,在单因素实验的基础上,采用Box-Behnken响应曲面法对影响梅花鹿角盘多肽超滤效果的关键因素进行优化探讨,确定最佳分离工艺条件:料液质量分数1.44%、操作压力0.13 MPa、操作时间60 min。在此条件下,膜渗透通量为1.72 L/m2·h,分离后的样品中多肽含量为45.2%,达到了较好的提纯效果。     

纳滤膜浓缩混合油过程中的操作条件研究

为解决传统的混合油浓缩过程中溶剂回收能耗高的问题,本文分别采用3种不同截留分子量的纳滤膜进行溶剂回收,并考察了操作压力、料液浓度等条件对分离性能的影响。在0.3MPa下,料液浓度在20%左右,采用NF-400膜,大豆油的截留率在20%以上,膜的渗透通量为0.33L/（m~2·h）。     

陶瓷膜处理乙醇发酵废水的工艺条件研究

发酵法生产乙醇的过程中产生大量废水,文中采用陶瓷膜处理乙醇发酵废水,考察了膜孔径、料液性质以及操作条件对过滤过程的影响。结果表明,陶瓷膜过滤乙醇发酵废水有较好的效果,化学需氧量(COD)去除率达80%,固体悬浮物(SS)截留率在99%以上。确定了孔径为200nm的膜管在pH值为8.0,错流速度为5m/s,温度为50℃,操作压力0.15MPa条件下操作,膜通量大于700L/(m2·h)。     

大豆乳清蛋白的超滤分离及膜污染分析

本文以大豆乳清蛋白为研究对象,采用孔径为5 nm的陶瓷膜对大豆乳清废水进行超滤实验,考察不同操作条件对超滤过程分离性能的影响,并结合Cake-complete模型对膜污染机理进行分析研究。实验结果表明:在0.15 MPa压力下,最大渗透通量为6.85 L·m~-2·h~-1;当压力由0.15 MPa增大到0.20 MPa时,浓差极化占主导因素,有效推动力降低,此时压差的增大对膜通量的影响不再显著。同时,乳清蛋白的截留率可通过料液p H进行调节,在p H为6左右时,截留率最高可达73.3%。此外,采用组合模型对实验数据的拟合效果最佳,拟合度达到0.99以上,说明膜污染过程并非由单一机理控制,而是由多种污染类型共同造成的。以上结果为进一步的工业应用奠定了基础。     

酪蛋白糖巨肽超滤分离的工艺优化研究

目的:研究超滤分离酪蛋白糖巨肽的最优工艺参数,以达到最佳超滤通量性能。方法:采用超滤方法分离乳清浓缩蛋白(WPC80)中的酪蛋白糖巨肽,研究料液pH值、操作压力和温度等对膜渗透通量的影响。利用SDS-PAGE凝胶电泳技术分析超滤截留液的相对分子量分布。结果:实验表明溶液pH7.0、操作压力0.3MPa、温度45℃时膜渗透通量最高,超滤酪蛋白糖巨肽的截留率达到97.54%,产物纯度达到92.45%,经SDS-PAGE凝胶电泳测定,酪蛋白糖巨肽的平均分子量68.86%为30.47ku,31.14%为19.22ku。结论:超滤技术是将酪蛋白糖巨肽与其他乳清蛋白分离的有效方法。     

膜分离技术在食用油脱胶及溶剂回收中的应用

为解决传统的混合油浓缩和溶剂回收能耗高的问题,探索了膜分离法在混合油脱胶及溶剂回收中的应用,并考察了操作压力和质量比对膜分离过程的影响.采用截留分子量5 000的PES5超滤膜脱除混合油中的磷脂,在0.3MPa下操作,磷脂截留率为63.5%,膜渗透通量达到40.74 L/m2·h.采用ADNF-4040纳滤膜回收混合油中的正己烷,其最大截留率为81%,对应的渗透通量为0.2L/m2·h.     

REVERSE OSMOSIS OF COTTAGE CHEESE WHEY. 1. Influence of Composition of the Feed

SUMMARY– Permeation rate, retention, and solute flux during reverse osmosis of whey and whey fractions were compared using two types of cellulose acetate membranes. When the feed solutions contained no molecules larger than lactose, concentration polarization had little influence on performance except at the highest available driving force (applied pressure minus difference between osmotic pressures of the feed and permeate = 37.8 atm). With the more complex feeds (whey and deproteinized whey), both concentration polarization and fouling of the membrane occurred. Concentration polarization decreased both permeation rate and retention. Fouling decreased permeation rate, but its influence on retention was variable and depended principally on the feed, the solute, and the available driving force. Proteins and other macromolecules in whey had a greater influence on performance during reverse osmosis than smaller solute molecules. With whey as feed, maximum permeation rates were achieved at low available driving forces (10-12 atm), and were similar for the two types of membranes (about 1 ml/cm²*sec). Increasing the available driving force increased retention and therefore reduced solute flux. Choice between the two membranes requires a compromise between extent of desalting and loss of lactose in the permeate.     

Carotenoids Concentration of Gac (Momordica cochinchinensis Spreng.) Fruit Oil Using Cross‐Flow Filtration Technology

Gac (Momordica cochinchinensis Spreng.) fruit, a traditional fruit in Vietnam and other countries of eastern Asia, contains an oil rich in carotenoids, especially lycopene and β‐carotene. Carotenoids in gac fruit oil were concentrated using cross‐flow filtration. In total recycle mode, effect of membrane pore size, temperature, and transmembrane pressure (TMP) on permeate flux and on retention coefficients has been exploited. Resistance of membrane, polarization concentration, and fouling were also analyzed. Optimum conditions for a high permeate flux and a good carotenoids retention are 5 nm, 2 bars, and 40 °C of membrane pore size, TMP, and temperature, respectively. In batch mode, retentate was analyzed through index of acid, phospholipids, total carotenoids content (TCC), total antioxidant activity, total soluble solids, total solid content, color measurement, and viscosity. TCC in retentate is higher 8.6 times than that in feeding oil. Lipophilic antioxidant activities increase 6.8 times, while hydrophilic antioxidant activities reduce 40%. The major part of total resistance is due to polarization (55%) while fouling and intrinsic membrane contribute about 30% and 24%, respectively.     

胡麻油掺假的快速检测方法的建立

为了便于快速、准确检测胡麻油的纯度,是否掺假等问题,建立一种应用于企业的快速检测胡麻油掺假的方法。试验收集8份不同企业生产的胡麻油及1份菜籽油,将胡麻油与菜籽油按照不同体积比例混合,充分振荡摇匀,利用阿贝折光仪测定20℃下各混合油的折光率,并建立掺假模型。结果表明:胡麻油与菜籽油体积掺比为40∶1和50∶1时,折光率变化不显著,其它掺比后的折光率均显著下降(P<0.05);建立掺假模型,其方程为:Y=-0.0071X+1.4777,R2为0.9943,当掺入的菜籽油体积分数高于3.23%时,即可检测其是否掺假。     

载姜黄素纳米乳液的制备及体外模拟消化特性研究

为提高姜黄素的水溶性和生物可利用度，本研究以选择性水解大豆蛋白为乳化剂，构建了稳定的姜黄素纳米乳液运载体系，对纳米乳液的制备过程中均质压力的影响进行研究，并对纳米乳液的粒径、Zeta-电位、浊度、微观结构以及胃肠消化特性进行表征。结果表明，姜黄素的溶解度与油相有显著关系（P<0.05），溶解度从大到小分别为中链甘油三酯（MCT）>菜籽油>玉米油>橄榄油>大豆油。以50 MPa为均质压力，制备得到的乳液平均粒径最小（265.00±4.14 nm）、Zeta-电位绝对值较大（-30.77±0.71 mV）、浊度最低。分别以菜籽油和MCT为油相制备得到载姜黄素纳米乳能抵抗胃蛋白酶的消化，在胃部保持一定的界面张力使乳液维持原有形态，而在小肠中消化，游离脂肪酸释放率达60%。将菜籽油和MCT以不同比例进行复配，发现随着菜籽油比例的增加，姜黄素的生物可利用度和保留率显著降低，其中，以菜籽油:MCT=3:7为油相的乳液具备与以纯MCT为油相的乳液几乎相同的姜黄素生物可利用度和保留率，接近70%。研究结果对封装和释放高亲脂性功能成分的传递系统的设计具有重要指导意义。     

Efficient degumming of crude canola oil using ultrafiltration membranes and bio-derived solvents

Vegetable oils derived from rapeseed and its genetic variant canola, are conventionally extracted from oilseeds by means of an organic solvent, typically hexane. Concerns regarding the toxicity of hexane have meant safer and more environmentally friendly solvents such as terpenes are becoming attractive. In this research, the degumming of canola oil/terpene mixtures using ultrafiltration is considered as a critical step in such an extraction process. Polysulfone (PSF) and polyethersulfone (PES) membranes were found to be ineffective in this application, as the oil appeared to cause swelling of the membrane structure. This meant that the original flux could not be restored after cleaning. Conversely, a ceramic membrane (MWCO 5 kDa) provided stable behaviour over several cycles of operation when cleaned with pure solvent at high cross-flow velocity at 40 °C. This membrane showed high phospholipid retention (95 ± 2%), although some oil was also retained (16 ± 3%). Cymene emerged as the most attractive of the three terpenes tested, with higher permeate flux and phospholipid rejection than limonene or pinene.Industrial relevanceWhile hexane has been traditionally used for oilseed extraction, toxicity concerns are likely to restrict its industrial use in the future. This article provides information to engineers and food scientists on the use of terpenes as an alternative solvent. In particular, the potential for ultrafiltration to be used in degumming of canola oil/terpene mixture is assessed. Our research shows that polymeric membranes are unlikely to be useful at scale in this application, as they are not readily cleaned for reuse. Conversely, a ceramic membrane of 5 kDa pore size provides the necessary rejection of phospholipids. There is some oil retention, that might require a downstream recovery step. The best results were obtained with cymene, suggesting this is a good target for industrial use.     

PROCESSING OF CRUDE PALM OIL WITH CERAMIC MICROFILTRATION MEMBRANE

Membrane separation technology offers a potential application in the processing of crude palm oil. Ceramic membranes with different pore diameters (0.45 and 0.2 micron) were used to conduct the study on micromembrane process. Quality parameters of membrane-processed oils examined included free fatty acid (FFA), carotene, fatty acid composition (FAC), phosphorus and iron contents. The effect of operating parameters such as transmembrane pressure, feed flow and time on permeate flux were evaluated. It was found that 'Ceraflo'ceramic membrane with a pore size of 0.45 micron was only able to reject 14% of phosphorus from the crude oil. Ceramic membrane with pore size of 0.2 micron showed a better phosphorus rejection of 56.8%. The permeate was found to contain 7.13 ppm of phosphorus. The 0.2 micron membrane was also able to remove more than 80% of the iron from crude palm oil. Pore sizes for both membranes were not small enough to remove other components such as FFA, and carotene. Both membranes showed a similar trend in which the permeate flux increased with transmembrane pressure and feed flow until a certain limit where the flux declined with increasing pressure and feed flow. The limits in transmembrane pressures for membrane with pore sizes of 0.45 and 0.2 micron were 1.65 and 1.25 bar, respectively. Whereas the limits in feed flow for 0.45 micron and 0.2 micron membranes were 9.2 and 9.8 L/min     

管式膜超滤生黄酒的研究

本文利用外压管式超滤装置,对生黄酒进行除浊除菌试验,探讨了压力和温度对生黄酒的透液通量的影响,考查了相关质量指标的变化规律。采用切割分子量为5万的有机膜,在0.30MPa、40℃条件下超滤,黄酒平均透液通量可达到75kg/m2•h左右。杂菌总数去除98%以上,不溶性固形物全部去除,粗蛋白仅保留21.55%。超滤过程对酒精度影响极小,对各种氨基酸的保留率有一定差别,总体保留率86.76%。对于多次使用的旧膜,可采用较长时间浸泡清洗。     

油菜籽中多酚的分布及加工过程对菜籽多酚含量的影响

对油菜籽壳粕和脱壳后的菜籽肉粕中提取液的总酚含量、对DPPH 自由基清除能力以及FRAP 抗氧化能力进行比较,并采用液质联用法对提取液中的主要成分进行鉴定,对其中的芥子酸和芥子碱进行定量分析。结果表明：菜籽肉粕提取液中的总酚含量、对DPPH 自由基清除能力以及FRAP 抗氧化能力约为菜籽壳粕中的两倍,芥子酸和芥子碱的含量分别为菜籽壳粕中的约2.5 倍和1.5 倍。通过对实验室溶剂除油的菜籽粕与工业高温粕比较发现,高温榨油过程会使菜籽的总酚含量、抗氧化性、芥子酸和芥子碱含量有所下降,其中总酚含量下降了12.06%,DPPH 自由基和FRAP 抗氧化值分别降低10.0% 和5.6%,芥子酸和芥子碱含量分别下降了5.6% 和21.12%。     

Separation of Sucrose and Reducing Sugar in Cane Molasses by Nanofiltration

Recovery of sugars from cane molasses is a promising approach to increase the added value of molasses and reduce its environmental pollution. In this work, for the first time, nanofiltration (NF) was used for the separation of sucrose and reducing sugar in cane molasses by a cascade diafiltration-concentration process. The retention difference between sucrose and reducing sugar by all the tested NF membranes was not distinct at 25 °C, while due to the thermal-induced pore size change and enhanced solute diffusivity, the NF retention behavior changed significantly at 60 °C, and the DL membrane with a sucrose retention of 96% and a reducing sugar retention 5% was selected for the process optimization and modeling. High temperature (55–60 °C), low permeate flux (below 15 Lm^?2 h^?1), and high sugar concentration resulted in a low retention of reducing sugar due to the dominant diffusive mass transfer, which was desirable for the molasses separation by NF. Mathematical modeling could well predict the diafiltration and concentration processes if using right sugar retention data. The deviations between prediction lines and experimental data in the cross-flow filtration of real solution were mainly caused by the permeate flux variation rather than membrane fouling. After diafiltration, the ratio of sucrose in total molasses sugar increased from 76.1 to 87.9%, while in the permeate of the second concentration step, the ratio of sucrose was only 2.4%. Thus, the retentate of diafiltration could be directly used for sucrose crystallization to avoid the accumulation of reducing sugar and salts, and the permeate of the second concentration step could be concentrated by NF270 at room temperature to produce syrup drinking.