茶油脱臭馏出物中甾醇精制的研究

采用乙醇萃取VE,皂化法提取茶油脱臭馏出物中甾醇化合物,以正己烷为结晶溶剂对甾醇化合物进行重结晶。VE最佳萃取参数:液料比3:1,搅拌时间30min,萃取温度55℃,搅拌速度80r/min。甾醇最佳的提取工艺条件:碱料比1(KOH):5,醇料比15(乙醇):1,皂化时间3h,温度85℃;最佳结晶工艺条件:液料比3:1,溶剂正己烷,结晶温度-2℃,结晶时间24h,三次重结晶后精制甾醇的纯度可以达到89.3%。     

姜叶叶绿素的提取及叶绿素铜钠的制备

研究姜叶叶绿素的提取工艺,并进行叶绿素铜钠的制备及其稳定性的初步分析.结果表明,提取姜叶叶绿素的最佳工艺条件为:以2:1的丙酮.95%乙醇混合溶液作提取溶剂,料液比1:30、浸提温度60℃、浸提时间5h;按先皂化后铜代工艺制备的叶绿素铜钠产品,具一定耐酸性,90℃以下热稳定性较好.     

植物甾醇提取新工艺

以甲酯化大豆油脱臭馏出物经离子交换吸附VE后得到富含甾醇的过柱液作为原料,以正己烷作为提取溶剂,采用冷却结晶的方法分离粗甾醇,再以丙酮作溶剂对粗甾醇进行重结晶.通过单因素和正交试验确定最佳结晶工艺条件:结晶时间18h,结晶温度2℃,料液比1/2(g/ml),在此条件下甾醇纯度为84.39%,用丙酮重结晶得到甾醇产品纯度为94.87%.     

基于山苍子核油的高纯度月桂酸的制备

以山苍子核油为原料,经酸炼、皂化酸化水解、减压精馏及混合溶剂结晶纯化工艺分离制备高纯度月桂酸,并采用单因素实验和正交实验优化了溶剂结晶纯化月桂酸的工艺。得到的最优溶剂结晶纯化工艺条件为:料液比1∶2∶10(m第二馏分∶V95%乙醇∶V正己烷),结晶时间4 h,结晶温度-17.5℃。在最优工艺条件下,月桂酸的纯度达到98%以上。该组合工艺具有条件温和、产品纯度高及溶剂易回收再利用等优点,适合于山苍子核油的深度开发利用。     

菜籽油脱臭馏出物中天然VE和植物甾醇提取工艺研究

不同的脱臭馏出物脂肪酸含量差别很大,为充分利用其中的天然VE和植物甾醇,针对脂肪酸含量低的菜籽油脱臭馏出物,采用酒精萃取天然VE。90%酒精、pH4.0,液料比4L/kg,在60℃、120r/min下搅拌萃取20min,VE提取率达68.82%,浓缩24.48倍。萃余物水相皂化,碱料比0.2kgNaOH/kg,水料比5L/kg,80℃下皂化8h后,经盐水洗涤,用乙酸乙酯萃取不皂化物中的植物甾醇,液料比7L/kg脱臭馏出物,在50℃、120r/min搅拌下萃取40min,萃取液1000r/min离心15min,甾醇提取率达75.97%,浓缩20.3倍。针对脂肪酸含量高的脱臭馏出物,2%碱水洗至酸价测不出,再用硅胶吸附法浓缩VE。硅胶用量为原料的3倍,吸附溶剂6号溶剂油用量9L/kg原料,在30℃下吸附1.25h,解吸溶剂石油醚/乙醇(1∶4)用量7L/kg原料,于室温下解吸0.75h,VE提取率达65.02%,浓缩12.4倍。在上述硅胶中用乙醇在室温下解吸0.75h,乙醇用量32L/kg原料,甾醇提取率达73.46%,浓缩10.4倍。两种工艺均取得了较好的效果。     

芦笋叶绿素铜钠盐制备过程中提取工艺的研究

采用超声法对芦笋叶进行了叶绿素的提取并合成了叶绿素铜钠盐。结果表明,芦笋叶绿素的最佳提取工艺条件为:提取溶剂为80%丙酮与95%乙醇体积比1:4,提取时间60min,提取温度70℃,液固比10:1,超声功率160W。提取的叶绿素溶液,经过皂化、酸化、铜代、成盐等步骤制成叶绿素铜钠盐,得率(以鲜叶计)为0.18%,产品质量符合国家标准GB3262-1982。     

天然山茶油皂液的制备工艺研究

利用天然山茶油为主要原料,以聚乙二醇为催化剂,乙醇为增溶剂,与氢氧化钾进行皂化制备天然山茶油皂液。通过单因素实验和正交实验优化天然山茶油皂液的制备工艺条件,并考察了产品的表面张力、临界胶束浓度、发泡性及乳化性。结果表明:制备天然山茶油皂液的最佳工艺条件为反应温度90℃、反应时间6 h、碱液(1 mol/L氢氧化钾乙醇溶液)添加量60 mL(10 g山茶油),在最佳工艺条件下皂化率可达到85. 24%;产品的临界胶束浓度为0. 95 g/L,最低表面张力为21. 07mN/m,5 min内泡沫高度由14. 54 cm降至13. 97 cm,泡沫稳定性为96. 08%,乳化分水时间为5. 06min,表明山茶油皂液具有优良表面活化性能。     

仙人掌叶绿素的提取及叶绿素铜钠盐的制备工艺研究

探讨了"米邦塔"仙人掌叶绿素的提取及制备叶绿素铜钠盐的工艺条件.结果表明,仙人掌叶绿素最佳提取工艺条件为:以80%丙酮及95%乙醇比例为3:1的混合溶液作浸提剂,料液比1:45,浸提温度40℃,浸提时间5h;提取的叶绿素,经过皂化、酸化、铜代、成盐等工序制成叶绿素铜钠盐,产品质量符合国家标准GB3262-82.     

乙醇处理对番茄红素提取的影响

主要对番茄皂化产物的乙醇处理方法和影响番茄红素提取的诸因素,如提取温度、提取时间、浸提料液比等进行了研究,结果表明:番茄皂化产物用95%乙醇处理3次后,再用二氯甲烷(原料与试剂比为1∶5)在30℃条件下震荡提取45min可以获得最佳的提取效果。     

大豆油馏出物中VE的分离及胶囊的制备

大豆脱臭馏出物结晶去除甾醇后,皂化液用量/原料0.3(w/w),皂化时间1.5h、皂化温度80℃,通过正己烷萃取分离,VE浓度达37%以上;采用β-环糊精为壁材,运用包络法对VE进行微胶囊化,产物收率达到64%.     

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