棉籽油混合油精炼技术

在工业化油脂精炼脱酸工艺中,目前主要有：①碱炼脱酸法;②无水醋酸法;③蒸馏脱酸法;④泽尼斯法;⑤混合油精炼法。其中,无水醋酸法是美国人Ｓｔａｌｅｙ在５０年代发明的,又称作５０—油工艺（５０ｏｉｌｐｒｏｃｅｓｓ）,仅在美国采用。蒸馏脱酸,即采用水蒸汽蒸馏的物理精炼法,多用于棕榈油、大豆油。泽尼斯法是瑞典泽尼斯（Ｚｅｎｉｔｈ）公司６０年代开发的精炼方式,它多在欧洲用于菜籽及低酸价、含胶质少、色素低的椰子油、蓖麻油等。通常广泛应用的碱炼脱酸法,由于在早期的间歇式碱炼中,油与碱接触时间１０～６０ｍｉｎ,…     

混合油在泽尼斯法脱酸的应用

将混合油精炼与泽尼斯精炼结合在一起,使得泽尼斯精炼法也可以精炼高酸值油脂,同时拥有混合油精炼的优点——中性油皂化机率低,皂脚夹油少,精炼效果好等。通过单因素试验以产品酸值和反应得率为指标研究了影响脱酸效果和反应得率的工艺参数并应用正交试验对其工艺条件进行优化,得出最佳工艺条件为:反应高度1 400 mm、反应温度65℃、混合油体积分数60%、碱液浓度0.075 mol/L、进料孔径0.5 mm、单孔进料流量1.0 m L/min。在最佳工艺条件下,产品酸值为0.27 mg KOH/g,反应得率为92.0%,酸值符合棉籽油二级油的标准。     

高游离脂肪酸米糠油用混合油精炼法精炼成食用油

<正> 采用混合油脱蜡和混合油碱炼法可以将高游离脂肪酸(FFA)含量的米糠油精炼成不皂化物含量低、色泽浅的烹调油。在高游离脂肪酸植物油的各种脱酸方法中,已经证明,使用已烷和碱液的混合油精炼是一种有效的精炼工艺。对于这一工艺的各种参数,例如混合油中油的浓度、碱的强度和超量碱数量,以及非离子表面活性剂的应用等,对脱酸的程度、精炼损失和油的色泽的影响已经知道了很多,而混合油精炼对于高FFA和色泽很深的米糠油的适用性的研究还很少。但有一个关于混合油精炼工艺的报告     

米糠混合油碱炼脱酸工艺效果的研究

研究了米糠混合油碱炼脱酸工艺条件对提高碱炼得率和降低谷维素、甾醇等营养成分损失率的影响。结果表明:高酸值米糠毛油采用混合油碱炼脱酸比毛油碱炼脱酸在提高碱炼得率、降低谷维素和甾醇损失方面有显著优势;最佳的米糠混合油碱炼脱酸工艺条件为碱炼温度55℃,总加碱量为理论加碱量加0.3%超量碱(占油质量),混合油浓度40%,碱液质量分数11.06%;在最佳条件下,米糠混合油碱炼得率71.62%,谷维素损失率63.22%,甾醇损失率43.76%,较米糠毛油碱炼脱酸的碱炼得率提高16.48个百分点,谷维素损失率降低30.56个百分点,甾醇损失率降低21.41个百分点。     

玉米混合油碱炼脱酸工艺效果及最佳条件研究

研究了玉米混合油碱炼脱酸对碱炼得率和脱色率,以及甾醇、维生素E损失率的影响,并对玉米混合油碱炼脱酸工艺条件进行了优化研究。通过正交试验及正交试验全概率分析,得到玉米混合油碱炼脱酸最佳工艺条件为:混合油浓度60%,碱炼温度60℃,碱液质量分数8.07%,总加碱量为理论加碱量和油质量0.4%的超量碱。在最佳工艺条件下,玉米油酸值(KOH)由3.62 mg/g降至0.55 mg/g,碱炼得率为95.46%,脱色率为43.66%,色泽为Y30 R2.5(罗维朋比色槽25.4mm),甾醇损失率为28.05%,维生素E损失率为28.74%。与玉米毛油碱炼脱酸相比,碱炼得率提高6.38个百分点,脱色率提高3.55个百分点,甾醇和维生素E损失率分别减少5.54个百分点和4.89个百分点。     

基于CFD流场分析的反应釜搅拌器结构改进

承压反应釜在固液混合过程中往往伴随强烈的热传递效应,而密度较低的粉末状固相介质与液体混合的难度相对较大,投料溶入效果不佳和物料结团漂浮等问题较常见。针对此类反应釜的搅拌不充分等问题,采用CFD技术指导反应釜内搅拌器结构进行设计和改进,对反应釜内的固液搅拌混合过程进行了三维数值模拟。数值计算采用多重参考系法(MRF),κ-ε湍流模式以及Mixture多相流模型,模拟了反应釜中的流场形态,通过混合过程的两相流计算得到固相体积分数的分布情况和变化规律,并在此基础上预测了混合时间。结果表明:改进后的搅拌器效果明显增强,该混合过程的CFD模拟可得到相对准确的流场分布及各项特性参数预测结果,可为该类反应釜搅拌器的设计和优化提供参考。     

超声波油脂精炼技术

超声波油脂精炼技术赵国志（国内贸易部西安油脂研究设计院）李咸生（陕西省咸阳市渭城区粮食局）目前，传统的油脂精炼技术主要有：化学破炼，泽尼斯精炼，物理精炼和混合油精炼法。其中，物理精炼法适合于高酸价的棕榈油及米糠油，混合油精炼法适合于含棉酚色素的棉籽油...     

高酸值废弃油脂脱酸系统设计与应用

为解决高酸值废弃油脂脱酸效果不佳的问题,根据生物柴油转酯化反应对原料油的要求,开发了废弃油脂深度脱胶—脱色—双塔串联脱酸工艺。利用化工模拟软件对废弃油脂脱酸系统进行了模拟,建立了脱酸系统流程模拟模块,输出了日处理900 t废弃油脂的脱酸塔和脂肪酸捕集塔的物料平衡表。对脱酸塔和脂肪酸捕集塔的塔直径、填料高度和填料类型进行选型,并进行了水力学校核,将其气相动能因子和运行负荷率控制在合理范围内。将所开发的废弃油脂深度脱胶—脱色—双塔串联脱酸工艺应用于实际大型生产线,长时间运行表明,该工艺可以将废弃油脂含磷量和脂肪酸含量分别降至3 mg/kg和0.3%以下。采用深度脱胶—脱色—双塔串联脱酸工艺处理高酸值废弃油脂,脱酸效果好,处理后的废弃油脂可作为优质的生物柴油原料。     

玉米胚芽毛油中杂质清理及设备配置

玉米胚芽预榨毛油中杂质的处理方法有沉淀法、过滤法、水化法等,浸出混合油中杂质的处理方法有静态过滤法、旋液分离法、动态过滤法等。通过对这些处理方法的比较,认为预榨毛油去杂的有效方法为水化除杂法,浸出混合油的去杂采用动态连续混合油过滤机较为理想。     

硅藻土油脂脱酸剂的制备研究

以硅藻土为原料进行了油脂脱酸剂的制备研究。首先考察碱液质量分数、固液比、处理时间和处理温度对脱酸效果的影响,得到硅藻土油脂脱酸剂的最佳制备条件为碱液质量分数25%、固液比1∶5、处理时间40 min、处理温度70℃;然后对脱酸工艺进行了优化,得到最佳脱酸条件为脱酸时间25 min、脱酸温度60℃;通过数据拟合得到了脱酸剂用量与脱酸油酸值的数学表达式;在最佳工艺条件下对亚麻籽油脱酸后,其酸值(KOH)由2.07 mg/g降至0.95 mg/g,能达到压榨一级油的标准,除含皂量略有升高外,其他主要的理化指标基本不变。     

MISCELLA REFINING OF ISOPROPANOL EXTRACTED COTTONSEED OIL

A technologically feasible cottonseed oil-isopropyl alcohol (IPA) miscella refining process was developed to produce Prime Bleachable Summer Yellow (PBSY) quality cottonseed oil. Individual steps necessary to refine cottonseed oil-IPA miscella were determined and improved. The miscella was first neutralized with 20 Baume (Be') caustic solution (50% excess) using a homogenizer. After centrifugation to remove soapstock, the two remaining liquid layers were separated and desolventized. The refined oils from bottom and top layers were then water washed using 12.5 and 20% hot water (w/w), respectively. Water washing efficiently recovered the oil from the top miscella layer and reduced soap and phosphorus contents. The water washed and dried oil from the bottom and top layers were treated with 0.5 and 4% (w/w) acid-activated bleaching clay, respectively. Good quality bleached oil was then obtained. However, the quality of bleached oil produced from the bottom layer was better than that of the top layer. Comparative experiments with both IPA and hexane miscellas showed that quality of the refined oil from cottonseed oil-IPA miscella is as good as that produced from the cottonseed oil-hexane miscella using the process developed in this study.     

油脂制备过程对油脂色泽的影响及应对措施

油脂中的呈色物质包括天然色素和加工色素。天然色素易脱除,而加工色素难脱除。讨论了在油料的预处理、油脂浸出、混合油净化、混合油蒸发等油脂制备过程中,产生或残留的非水化磷脂、蛋白质、糖类等杂质,受热氧化或相互结合产生加工色素,导致油脂色泽加深。采用Alcon工艺、挤压膨化工艺,且加强对混合油的净化处理,可减少非水化磷脂的转化量及蛋白质、糖类等物质的含量,采用负压蒸发工艺可降低混合油蒸发的温度,从而减少加工色素的产生,改善油脂的色泽。     

棉仁膨化一次浸出及混合油精炼工艺实践

介绍了棉仁膨化一次浸出与混合油精炼相结合的棉籽油制取工艺流程和工艺技术参数。该工艺与预榨浸出工艺相比,具有提高棉籽油品质、得率和节约能源的优点,值得推广应用。     

Characterisation of dairy emulsions by NMR and rheological techniques

Droplet size distribution strongly affects macroscopic properties of emulsions. In this work rheological and NMR (nuclear magnetic resonance) analyses were performed to evaluate material properties as well as droplet size distribution and possible flow-induced alteration. The investigated materials were commercial dairy emulsions, based on milk, vegetable fats, a mixture of sugars, emulsifiers (hydrophilic or lipophilic) and natural stabilizers (carrageenan and guar gum). Rheological properties of three different dairy emulsions were related to the droplet size distribution obtained by NMR and dynamic light scattering (DLS) techniques. NMR seems to be a particularly useful technique because no previous sample treatment is necessary, whereas DLS requires a significant emulsion dilution that could change the droplet size distribution. Obtained results evidence the effect of two relevant ingredients (surfactants and fats) on rheological properties and droplet size distribution of tested emulsions. For sample containing sunflower oil and a hydrophilic emulsifier, rheo-NMR evidenced mechanical instabilities also confirmed by rheological tests. Comparison of results about the droplet size distribution evaluated by NMR and DLS evidenced that in this case sample dilution could affect size distribution. Finally, rheo-NMR was confirmed to be a powerful instrument capable of determining the material structure and alterations induced by the flow.     

基于Fluent低压旋流喷嘴下游流场数值模拟及分析

运用Fluent软件模拟了低压旋流喷嘴下游流场喷雾情况。利用欧拉-拉格朗日模型模拟气液两相耦合流动。模拟显示:喷嘴喷雾形状为空心锥状,与实验得到的喷雾形状相符。喷雾的液滴速度分布于15～25m/s之间,且随轴向距离的增大而减小;喷雾的液滴直径沿轴向距离增大而增大。     

One-step High Internal Phase Pickering Emulsions stabilized by uncracked micronized orange pomace

High Internal Phase Emulsions (HIPE) were formulated using 1% w/w orange pomace (i.e. uncracked micro-scaled byproduct powder) as sole stabilizer, from a quick and simple process, with 80% of sunflower oil and 20% of water in the liquid phase. Various indicators were monitored over a 2-month storage at T_amb, such as droplet size distribution, flow and viscoelastic properties, multi-scale microstructure (light and confocal microscopy). HIPPEs were stable towards coalescence and drainage, showing the complementarity between the anchoring insoluble fraction acting as Pickering particles at the oil-water interface and the viscosifying/film-forming soluble compounds. The oil droplet size distribution remained the same, and no significant change could be quantified regarding the elastic modulus, the yield stress or the viscosity of the emulsions in 60 days. However, changing the oil source from sunflower to another vegetal or synthetic oil could lead to unstable systems.     

Steady and Dynamic Shear Rheological Properties,and Stability of Non-Flocculated and Flocculated Beverage Cloud Emulsions

Rheological properties of single-phase, and emulsions containing modified starch and gum arabic as surface active hydrocolloids, as well as xanthan and tragacanth gums as stabilizers were evaluated under steady and dynamic shear testing conditions using a control stress rheometer. Emulsions were formed by 9% and 14% gum concentrations with oil concentration maintained at 9% thus giving a 1:1 and 1.5:1 surface active agent to oil ratio, respectively. The rates of droplet coalescence and creaming, for a total of 8 emulsions, as a function storage time before and after dilution in a simulated fruit beverage were then investigated. Steady shear (flow curve) were well described by the Carreau model at shear stress ranging from 0.01 to 100 Pa. All prepared water phases indicated a zero-shear viscosity plateau followed by shear thinning behavior with flow behavior index (n) ranging from 0.51 to 0.79 for 14% starch-0.3% xanthan and 14% gum arabic-0.8% tragacanth stabilized emulsions, respectively. The water phase flow property data were well fitted by the Einstein equation and its expansions. The dynamic rheological properties of water phase and emulsions were also evaluated for G′(ω) and G″(ω) from 1 to 50 rad/s. Similar curves were obtained with varying degrees of deviations (G′ from G″) for different emulsions. Starch-xanthan emulsion and associated water phase at 1.5/1 agent to oil ratio demonstrated viscoelastic behavior (G′ ≥ G″) with lower droplet coalescence and creaming rates. On the other hand, gum arabic-xanthan emulsion at 1:1 agent to oil ratio showed the highest rate of droplet coalescence and a greater degree of creaming. It was speculated that the lower stability of gum arabic-xanthan emulsion could be related to the denaturation of proteinaceous part in the gum and loss of emulsification capacity due to lower pH and pasteurization.     

Droplet characterization and stability of soybean oil/palm kernel olein O/W emulsions with the presence of selected polysaccharides

Droplet characteristics, flow properties and stability of egg yolk-stabilized oil-in-water (O/W) emulsions as affected by the presence of xanthan gum (XG), carboxymethyl cellulose (CMC), guar gum (GG), locust bean gum (LBG) and gum Arabic (AG) were studied. The dispersed phase (40%) of the emulsions was based on soybean oil/palm kernel olein blend (70:30) that partially crystallized during extended storage at 5 °C. In freshly prepared emulsions, the presence of XG, CMC, GG and LBG had significantly decreased the droplet mean diameters. XG, LBG, GG and CMC emulsions exhibited a shear-thinning behavior but AG emulsion exhibited a Bingham plastic behavior and control (without gum) emulsion almost exhibited a Newtonian behavior. Both control and AG emulsions exhibited a severe phase separation after storage (30 days, 5 °C). The microstructure of stored XG emulsion showed the presence of partially coalesced droplets, explaining a large increase in its droplet mean diameters. Increases in droplet mean diameters and decreases in flow properties found for stored GG and LBG emulsions were attributed to droplet coalescence. Nevertheless, the occurrence of droplet coalescence in these emulsions was considered to be small as no free oil could be separated under centrifugation force. Increases in flow properties and excellent stability towards phase separation found for stored CMC emulsion suggested that CMC could retard partial coalescence. Thus, the results support the ability of CMC, GG and LBG in reducing partial coalescence either by providing a sufficiently thick continuous phase or by acting as a protective coating for oil droplets.     

无水酒精恒沸精馏塔的动态模拟计算

对无水酒精恒沸精馏工艺中恒沸精馏塔进行模拟计算。首先针对恒沸精馏塔利用各组分相平衡关系建立MESH方程，同时考虑到乙醇-水-苯体系具有很强的非理想性的液相，利用马丁-侯81型状态方程(M～H EOS)确定气相逸度和焓，采用松弛法计算得到三元组分在各层理论塔板上的组成情况。为了研究提馏段理论塔板数对塔底产品的影响，在进料条件确定的条件下，改变提馏段理论塔板数，得到了塔底产品的不同组成的变化特性，为恒沸精馏塔的操作与设计提供参考，验证了动态模拟的正确性和优越性。     

非共沸烃／醇型混合溶剂浸出大豆的研究──Ⅲ．部分非蒸发溶剂循环工艺的初步研究

实验表明，在２５℃下静置后自动分层的混合油体系中，９５％以上的大豆毛油被富集在富油相中，而富含乙醇相中的浸出物含量通常只有５％左右。在此基础上提出了在混合溶剂浸出技术中采用部分非蒸发溶剂循环工艺的设想方案，并进行了初步的实验验证。实验结果表明，循环使用中的混合溶剂，其取油能力基本没有大的下降，可以在豆片的浸出过程中反复循环使用；残油率指标虽有所上升，但随着循环次数的增多，呈渐趋平衡的趋势，并保持在一个可以接受的水平上，因而有关部分非蒸发溶剂循环工艺的设想方案是可行的，值得进行进一步的扩大中试考察验证，以便确定其在工业化规模生产中运用的实际可行性。