米糠一次浸出及米糠油物理精炼

米糠作为中低含油量的一种特殊油料,很适于通过一次浸出提取毛糠油.米糠一次浸出需经历米糠预处理和米糠浸出两个阶段,米糠预处理的方法有3种:蒸炒、造粒、膨化,其中膨化又分为千式膨化和湿式膨化两种方式;米糠的浸出制油工艺过程具有与其他大宗油料不尽相同的工艺、设备要求,主要体现在物料浸出与湿粕脱溶两道工序上.米糠浸出所得到的毛糠油为一种高酸值毛油,采用物理精炼工艺在提高油脂精炼率和经济效益方面具有明显的优势.米糠油物理精炼工艺过程包括脱胶、脱色、脱酸、脱蜡、脱脂,关键工序是蒸馏脱酸,脱胶、脱色是其至关重要的前处理工序.米糠油物理精炼工艺在实际生产应用中可根据毛糠油的原料情况和精糠油的成品质量等级要求,结合化学精炼工艺进行综合精炼或进行各种档次成品油的生产调节,取得物尽其用的效益.     

Sub-critical water treatment of rice bran to produce valuable materials

The target of this study is application of sub-critical water as a green solvent for hydrolysis of rice bran and extraction of its oil in order to obtain value-added materials. Experiments were carried out at temperatures ranging from 100 to 360 °C with 5 min residence time in a batch reactor. Four phases were isolated after reaction: hexane-soluble, acetone-soluble, water-soluble, and solid residue phases. Rice bran oil was successfully and efficiently obtained by sub-critical water extraction. Significant increases of total organic carbon (TOC) and total nitrogen (TN) in the water phase were also observed, because polysaccharides and proteins (generally bio-macro polymers) in rice bran were hydrolysed by sub-critical water. The highest yields of TOC and TN were 140 and 13 mg/g dry matter, respectively. As a result, varieties of compounds, such as amino acids, organic acids, and water-soluble saccharides, were identified in the water phase. In particular, significant amounts of water-soluble sugars (maximum yield of total sugars was nearly 190 mg/g dry matter) proved that sub-critical water was a promising medium for dissolution of biomass in water. Acetone-soluble contents were attributed to tar, carbonized biomass, and in general, water- and hexane-insoluble compounds. Solid residue consisted of mainly un-reacted rice bran and insoluble inorganic compounds.     

超声辅助水酶法提取米糠油的研究

研究了超声辅助水酶法对米糠油提取的影响,并利用响应面法对米糠油提取工艺进行了优化。结果表明,复合酶(纤维素酶、中性蛋白酶和淀粉酶质量比1∶1∶1)和超声辅助处理有利于米糠油的提取。提取米糠油的最佳条件为:复合酶添加量1.5%(占米糠质量),料液比1∶6,酶解时间3 h,酶解温度39.5℃,pH 5.4,超声功率198 W,超声时间15 min。在最佳条件下,米糠油提取率可达88.3%,所得米糠油中谷维素含量为2.2%。     

米糠油谷维素提取方法研究进展

谷维素是从米糠油或胚芽油等谷物油脂中提取的一种天然混合物,是米糠油深加工过程中产生的极有价值的副产品。本文从谷维素的组成、提取和纯化方法进行综述,重点阐述不同提取工艺的特点和优缺点,分析实验中遇到的实际问题并且提出解决的办法。      

米糠微波灭酶及提油工艺研究

以新鲜米糠为原料,利用工业化连续微波灭酶设备进行灭酶处理,然后对灭酶米糠的提油工艺进行了研究。实验结果表明,微波辐射具有很好地降低米糠中解脂酶活性的作用,并且得到最佳处理厚度为0.9cm,处理时间为4min,每小时处理量达到36kg。米糠油浸出的最佳工艺条件是:浸出温度55℃,浸出时间2h,料液比1∶6,在此条件下米糠油得率达到90.04%,较未灭酶米糠油得率有明显提高。      

热风辅助射频加热对米糠储藏稳定性的影响

采用热风辅助射频(HA-RF)技术对米糠进行稳定化处理并与挤压处理对比,研究米糠在25、35和45℃下储藏过程中水分含量、水分活度、色度、游离脂肪酸含量和过氧化值的变化,选取关键品质利用其动力学模型来预测货架期.结果表明储藏过程中米糠各项品质变化较慢,而游离脂肪酸含量较为适合作为预测货架期的关键指标,新鲜米糠(FRB)...     

超临界CO2流体萃取米糠油研究

通过超临界CO2流体萃取米糠油研究,总结萃取压力、萃取温度、萃取时间和物料水分含量对米糠出油率影响。结果表明,最适宜萃取条件为:萃取压力30 MPa、萃取温度45℃、萃取时间80 min、物料水分含量为5％～6％,出油率达14．32％;同时测定超临界CO2流体萃取米糠油中脂肪酸甘油酯组成,得出油酸甘油酯、亚油酸甘油酯和棕榈酸甘油酯占总脂肪酸甘油酯90％以上,其中,油酸甘油酯和亚油酸甘油酯占总脂肪酸甘油酯70％以上;通过超临界CO2法与压榨法比较,超临界CO2流体法萃取米糠油不饱和脂肪酸含量较高,理化指标也优于压榨法,因萃取温度低,防止提取过程中油脂氧化,因此超临界CO2流体萃取是一种较好提取米糠油方法。     

微波-超声协同辅助提取燕麦麸油的研究

本研究采用微波-超声协同辅助提取技术从燕麦麸皮中提取燕麦麸油,考察了溶剂配比、微波功率、液料比和作用时间对燕麦麸油得率和抗氧化活性的影响。试验结果表明,燕麦麸油的最佳微波-超声协同辅助提取工艺条件为正己烷∶乙醇=1∶1(V/V)、功率300 W、液料比12∶1(m L/g)、作用时间60 s,在此条件下,燕麦麸油的得率为6.88%;与溶剂浸提相比,微波-超声协同辅助提取的燕麦麸油具有更强的抗氧化活性,对DPPH自由基清除的IC50值1.064 mg/m L,其中主要的抗氧化活性物质总酚、生育酚(VE)、甾醇的含量分别为(1 531.04±10.28)、(84.15±2.47)mg/kg和(578.23±7.04)mg/100 g;GCMS结果显示微波-超声协同辅助提取燕麦麸油的主要脂肪酸组成为棕榈酸、油酸、亚油酸,与溶剂浸提的无明显差异。     

米糠油酶解条件研究

利用脂肪酶催化油脂水解成脂肪酸和甘油,从而得到脂肪酸产品是一种温和的油脂水解方法.为了提高产品质量和水解效率,研究了米糠油酶解时反应温度、水/米糠油摩尔比及脂肪酶用量对米糠油水解效果的影响.试验结果表明,当水/米糠油摩尔比为40:1,加入6%的脂肪酶,在55℃下水解7 h,其水解率可达92.54%,水解较彻底.     

米糠油生理功能及制取工艺的研究

概述了米糠油的营养价值及生理功能,详细介绍了米糠制油技术及米糠油精炼技术,并分析了各种米糠油精炼技术的优缺点.     

超临界流体萃取与二乙醇胺法综合制备米糠油

以市购米糠为原料,采用超临界流体萃取法提取米糠油,并对毛糠油的简化精炼工艺进行研究。原料经微波预处理降低解脂酶活性后,利用超临界CO2分段萃取,先后控制条件15MPa、32℃、1.0h和35MPa、40℃、4.0h获得毛糠油Ⅰ、Ⅱ。用二乙醇胺处理毛糠油Ⅱ,通过单因素实验和正交实验得出二乙醇胺法精炼毛糠油的最佳条件为:二乙醇胺加入量为油重的9%,精炼温度为50℃,振荡时间为15min。在此条件下精炼毛糠油,油脂酸价可降至0.85mgKOH/g,酸价降低率达到94.33%。超临界流体萃取与二乙醇胺法精炼综合处理所得米糠油清澈、透明,谷维素含量为1.73%,色度达到了国家标准。     

Liquid–liquid equilibria for systems composed of rice bran oil and alcohol-rich solvents: Application to extraction and deacidification of oil

The liquid–liquid equilibria of systems composed of rice bran oil, free fatty acids, ethanol and water were investigated at temperatures ranging from 10 to 60 °C. The results of the present study indicated that the mutual solubility of the compounds decreased with an increase in the water content of the solvent and a decrease in the temperature of the solution. The experimental data set was correlated by applying the UNIQUAC model. The average variance between the experimental and calculated compositions was 0.35%, indicating that the model can accurately predict behavior of the compounds at different temperatures and degrees of hydration. The adjustment of interaction parameters enables both the simulation of liquid–liquid extractors for deacidification of vegetable oil and the prediction of phase compositions for the oil and alcohol-rich phases that are generated during cooling of the stream exiting the extractor (when using ethanol as the solvent).     

醇法提取小米糠油工艺优化

以小米糠为原料,乙醇为提取剂,采用醇法提取小米糠油,并对小米糠粉的前处理方式、乙醇体积分数、浸提时间、料液比、浸提温度5个因素对小米糠提油率的影响进行了研究和优化,得到的最佳条件为烤箱121℃焙烤15 min、乙醇体积分数95%、料液比1∶5. 84、浸提时间2. 84 h、浸提温度63. 4℃,该条件下的小米糠提油率为88. 65%。     

超临界二氧化碳萃取米糠油的生产工艺研究

以米糠为原料,对超临界二氧化碳萃取米糠油进行了研究。结果表明,超临界二氧化碳萃取米糠油的较优工艺务件为:萃取压力30MPa,萃取温度42℃,CO2流量为60kg/h,萃取时间60min。在最佳萃取条件下,米糠中脂肪的抽提率达到85.53%(脂肪),米糠毛油中的脂肪含量达94%,而不饱和脂肪酸占总脂肪的71%以上。精炼后的米糠油理化参数均达到国家标准。     

山稻米糠油营养成分分析与比较

分别对江南地区栽培较广的3个山稻品种进行了米糠含油率、脂肪酸组成、不皂化物含量与组成、γ-谷维素含量的分析,并与水稻和旱稻米糠油进行对比。结果表明,3个山稻品种米糠含油率均高于水稻和旱稻,最高的是山稻18号,含油率达(23.08±2.20)%;脂肪酸组成最丰富的是山稻14号,共检出14种脂肪酸,必需脂肪酸质量分数最高的是山稻5号,仅次于旱稻,达35.83%,最低的是14号,为28.31%;米糠油不皂化物中含量最高的是甾醇类化合物,3个山稻品种中植物甾醇质量分数均超过总不皂化物的50%;山稻18号角鲨烯含量最高,仅次于旱稻,达1 168.91mg/kg; 5种米糠油中γ-谷维素含量从高到底分别为山稻18号、山稻5号、旱稻、山稻14号和水稻,γ-谷维素质量分数分别为(20.74±0.08)、(18.26±0.08)、(16.68±0.88)、(14.72±0.31)、(12.61±0.11) mg/g, 5个品种间γ-谷维素含量差异极显著(P<0.01)。山稻米糠含油率较高,脂肪酸组成丰富,油中植物甾醇和γ-谷维素等含量均高于传统栽培的水稻和旱稻,是一种极具潜力的食用油。     

Optimization of enzymatic degumming process for rice bran oil using response surface methodology

Response surface methodology was used to determine the optimum processing conditions for enzymatic degumming of rice bran oil. Reaction time, enzyme dosage, level of water added and temperature were the factors investigated with respect to phosphorus and free fatty acids contents. A D-optimal design, with four variables and two response functions, was employed to study the effect of the individual variables on the response functions. For each response, second-order polynomial models were developed using multiple linear regression analysis. Applying desirability function method, optimum operating conditions were found to be reaction time of 4.07 h, enzyme dosage of 50 mg/kg, added water of 1.5 ml/100 g and temperature of 49.2 °C. At this optimum point, phosphorous and free fatty acids contents of degummed oil were found to be 8.86 mg/kg and 2.01 g/100 g as oleic acid, respectively.     

挤压稳定化对不同贮藏时间米糠制备米糠毛油品质的影响

以不同贮藏时间的米糠为原料,研究米糠挤压稳定化处理对米糠毛油品质的影响。结果表明:相比米糠未稳定化制备的米糠毛油,米糠挤压稳定化处理增加米糠毛油的酸值和过氧化值;随着米糠贮藏时间的延长,米糠挤压稳定化处理与未稳定化处理制备米糠毛油酸值和过氧化值相差幅度增加;米糠挤压稳定化处理对米糠毛油的脂肪酸组成影响较小,仅亚麻酸含量显著下降,米糠挤压稳定化处理对米糠毛油碘值和皂化值没有显著影响;米糠挤压稳定化处理显著降低米糠毛油磷脂、水分及挥发物含量,随着米糠贮藏时间的延长,米糠挤压稳定化处理与未稳定化处理制备米糠毛油磷脂含量相差幅度增大;此外,米糠挤压稳定化处理可显著提高米糠毛油谷维素含量。     

Comparison of rice bran oil and wax yields; a systematic approach to wax ester analysis

Rice bran oil (RBO) comprises 2–4% of rice bran wax (RBW) which contains wax esters (WE), hydrocarbons and other minor constituents, and there is still a lack of information on the RBW yields by various extraction methods and the WE contents in RBW. In this study, the yields of RBO and RBW extracted with Soxhlet and microwave‐assisted extraction (MAE) were compared with establish suitable RBW preparation methods. HPLC methods were also developed to determine the WE contents in RBW. MAE with hexane was the most efficient method for higher RBW yields as well as higher WE contents. The HPLC analysis proved that around half of the refined RBW consists of WE. The results established an efficient procedure for RBW preparation, which includes MAE with hexane, RBO refinement, winterisation, solvent fractionation and HPLC separation.     

米糠油制取工艺的研究

对米糠油的制取和精炼工艺进行了研究。结果表明,米糠油浸出的最佳工艺条件是:米糠含水量7%,粉碎至50目,浸出溶剂异丙醇,浸出温度60℃,pH 6.0,料液比1∶5,浸出时间2 h。米糠油精炼的最佳工艺条件为:碱炼初温45℃,KOH浓度18.5%,超碱量0.4%;采用二次脱色工艺,第1次活性白土加量4%,脱色时间30 m in,脱色温度90℃;第2次活性白土加量3%,脱色时间15 m in,温度85℃,真空度0.1 MPa;在真空度0.08 MPa、温度180℃、脱臭时间1.5 h条件下,可以脱除米糠油中的臭味成分,保持米糠油的固有味道。     

米糠油指纹图谱的构建及掺伪定量检测技术研究

为完善米糠油掺伪的定量检测系统,采用恒温毛细管气相色谱法建立了米糠油指纹图谱,对米糠油进行模拟掺伪,建立了米糠油中廉价油脂掺伪量与特征脂肪酸含量的一元线性模型。结果表明:掺伪棕榈油最佳线性模型为YC16∶0=16.719X+18.722(R2=0.993 7);掺伪菜籽油最佳线性模型为YC22∶1=0.158 2X+0.350 7(R2=0.991 0),菜籽油掺伪量2%以上适用;掺伪棉籽油最佳线性模型为YC14∶0=0.004X+0.316 8(R2=0.981 3),棉籽油掺伪量17%以上适用;掺伪大豆油最佳线性模型为YC18∶3=0.090 6X+2.456 4(R2=0.992 5),大豆油掺伪量24%以上适用。