模拟高酸值菜籽油的不同脱酸方法工艺优化及脱酸效果比较

以菜籽油为原料,模拟出高酸值植物油,分别采用两次碱炼脱酸法、乙醇溶剂多次萃取法和分子蒸馏-碱炼脱酸法进行脱酸,探讨模拟高酸值菜籽油碱炼最大脱酸程度及该脱酸程度下最佳脱酸方案,最后应用于高酸值薏米米糠油进行验证。研究结果表明,模拟高酸值菜籽油碱炼脱酸的最大脱酸程度为60 mg KOH/g; 3种方法经优化后,两次碱炼脱酸后精炼油酸值为0. 111 mg KOH/g,总得率为34. 82%;乙醇萃取脱酸后精炼油酸值为3. 158 mg KOH/g,总得率为47. 77%;分子蒸馏-碱炼脱酸后精炼油酸值为0. 280 mg KOH/g,总得率为57. 45%。最佳脱酸方案为分子蒸馏-碱炼脱酸,其工艺为:在蒸发器温度165℃、内冷器温度30℃、转速365 r/min条件下分子蒸馏后,采用60 g/L的NaOH溶液在0℃下脱酸,100 g/L的Na Cl溶液洗脱皂脚后分离得最终脱酸油。高酸值薏米米糠油经最佳工艺脱酸后,其酸值由63. 41 mg KOH/g降至0. 441 mg KOH/g,总得率为57. 05%。实际体系和模拟体系脱酸结果一致性较好,说明模拟所得最佳脱酸工艺具有可行性。     

玉米胚芽油碱炼脱酸过程中保留两态植物甾醇的研究北大核心CSCD

探究碱炼脱酸过程中,不同工艺条件对玉米胚芽脱酸油中两态植物甾醇(游离态和酯态植物甾醇)含量变化的影响。在单因素试验的基础上,通过正交试验确定了最佳工艺条件。结果表明:影响玉米胚芽油碱炼脱酸中两态总植物甾醇绝对质量保留率的因素主次顺序为反应初始温度>碱液质量分数>超量碱量;最佳碱炼脱酸工艺条件为反应初始温度55℃,碱液质量分数10%,超量碱量为理论碱量的20%;在最佳工艺条件下,两态总植物甾醇绝对质量保留率为82.79%,其中游离态植物甾醇含量为297.390 mg/100 g,酯态植物甾醇含量为785.503 mg/100 g,精炼率为86.20%,玉米胚芽脱酸油酸值(KOH)为0.24 mg/g。     

玉米胚芽油碱炼脱酸过程中保留两态植物甾醇的研究

探究碱炼脱酸过程中,不同工艺条件对玉米胚芽脱酸油中两态植物甾醇(游离态和酯态植物甾醇)含量变化的影响。在单因素试验的基础上,通过正交试验确定了最佳工艺条件。结果表明:影响玉米胚芽油碱炼脱酸中两态总植物甾醇绝对质量保留率的因素主次顺序为反应初始温度碱液质量分数超量碱量;最佳碱炼脱酸工艺条件为反应初始温度55℃,碱液质量分数10%,超量碱量为理论碱量的20%;在最佳工艺条件下,两态总植物甾醇绝对质量保留率为82.79%,其中游离态植物甾醇含量为297.390 mg/100 g,酯态植物甾醇含量为785.503 mg/100 g,精炼率为86.20%,玉米胚芽脱酸油酸值(KOH)为0.24 mg/g。     

混合油精炼棉籽油磷脂含量的影响因素研究

以浸出棉籽混合油为原料,采用稀酸水化脱胶、碱炼脱酸的混合油精炼工艺,考察了混合油精炼过程中混合油浓度、水化温度、水化时间、碱炼温度、碱炼时间对成品棉籽油磷脂含量和精炼得率的影响。结果表明:最佳工艺条件为混合油浓度80%、水化温度45℃、水化时间30 min、碱炼温度50℃、碱炼时间60 min,在最佳条件下,棉籽油精炼得率90.9%,色泽Y35 R4.2(133.4 mm槽),酸值(KOH)0.14 mg/g,磷脂含量69 mg/kg。     

提高米糠油中谷维素含量的脱酸工艺研究

对米糠油进行脱蜡和磷酸-草酸辅助水化脱胶,再联合碱炼脱酸、蒸馏脱酸两段脱酸工艺进行脱酸,研究碱炼脱酸保留酸价以及两段脱酸工艺对谷维素留存率的影响。以谷维素含量、脱酸率、精炼率为考察指标,在单因素试验的基础上采用响应面试验优化脱酸工艺。结果表明,原油酸价(KOH)为22～25 mg/g时,碱炼脱酸保留酸价(KOH)取5 mg/g,原油酸价(KOH)为27～33 mg/g时,保留酸价(KOH)取6 mg/g,原油酸价(KOH)为35～37 mg/g时,保留酸价(KOH)取7 mg/g,谷维素留存率较高。米糠油碱炼脱酸的最佳工艺条件为温度25℃,时间22 min,碱液质量分数16. 91%,加碱量为理论碱量加0. 1%的超碱量;蒸馏脱酸的最佳工艺条件为温度225℃,时间86 min,真空度0. 098 MPa。在最佳工艺条件下,碱炼脱酸后谷维素含量为2. 05%,脱酸率为77. 78%,精炼率为80. 05%;蒸馏脱酸后谷维素含量由2. 05%升高到2. 16%,接近原油(2. 15%),脱酸率为90. 83%,精炼率为92. 42%。     

高酸值花椒籽油的醇萃取-碱炼混合脱酸工艺研究

以高酸值花椒籽油为原料,选择醇萃取-碱炼混合法精炼花椒籽油。以酸值、脱酸率或精炼率为指标,采用单因素实验和正交实验分别考察了初次脱酸和二次脱酸工艺中各参数对花椒籽油脱酸效果的影响。实验结果表明,在初次脱酸实验中95%乙醇与花椒籽油的液料比为2.5∶1m L/g,二次脱酸实验中乙醇浓度为65%、氢氧化钠浓度为1.4%、乙醇-Na OH溶液与花椒籽油的液料比为2∶1m L/g、反应温度为60℃的条件下,酸值为76.60mg KOH/g的花椒籽油可降低到0.38mg KOH/g。     

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。     

高酸值米糠油物理蒸馏法脱酸的研究

因解脂酶作用,米糠油酸值通常都较高,但采用碱炼脱酸存在炼耗高、助剂残留、精炼率低等问题。物理蒸馏法脱酸具有工艺简单、精炼率高、产品稳定性好等优点。采用单因素试验和正交试验方法,研究物理蒸馏法脱酸最佳工艺条件。结果表明,温度220℃,真空度85kPa,脱酸时间100min时脱酸效果较好,脱酸后,米糠油酸价为1.93mg/g,精炼率为97.6%。     

正交试验优化猪网油实验室碱炼脱酸工艺

采用实验室碱炼法脱除高酸值猪网油中的游离脂肪酸,研究碱液质量分数、超碱量、碱炼时间和碱炼初温对猪网油酸值和得率的影响。在单因素试验的基础上,设计四因素三水平正交试验,对猪网油实验室碱炼脱酸工艺参数进行优化。最佳碱炼脱酸条件：碱液质量分数21%、超碱量0.1%、碱炼时间70 min、碱炼初温45 ℃。采用上述脱酸条件,所得猪网油酸值为0.125 5 mg KOH/g、得率为78.89%,说明此方法可以有效脱除猪网油中的游离脂肪酸。     

米糠油萃取脱酸结合吸附脱酸工艺效果研究北大核心CSCD

为了在脱酸的同时尽可能保留米糠油中的营养成分,采用乙醇萃取脱酸结合碱性微晶纤维素吸附脱酸的低温物理脱酸技术对米糠油进行脱酸。以乙醇萃取脱酸米糠油为原料,以脱酸率为考察指标,采用单因素实验和正交实验对米糠油的吸附脱酸工艺条件进行了优化,同时对比了碱炼脱酸与乙醇萃取脱酸结合吸附脱酸对米糠油品质的影响。结果表明:最佳吸附脱酸工艺条件为碱性微晶纤维素添加量3.0%、吸附时间2.0 h、吸附温度40℃,在此条件下米糠原油经乙醇萃取脱酸结合吸附脱酸处理后,酸值(KOH)由35.04 mg/g降到0.92 mg/g,谷维素的保留率为73.0%,总甾醇保留率为74.3%,总生育酚保留率为56.5%;而米糠原油经碱炼脱酸处理后,酸值(KOH)由35.04 mg/g降到1.16 mg/g,谷维素的保留率为60.1%,总甾醇保留率为65.6%,总生育酚保留率为44.6%。可见,与传统碱炼脱酸相比,萃取脱酸结合吸附脱酸的方法对米糠油中谷维素、甾醇、生育酚的保留率更高,对游离脂肪酸的脱除效果更好。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the