无机陶瓷膜微滤制备食品级大豆浓缩磷脂的研究

采用无机陶瓷膜微滤工艺除去饲料级浓缩磷脂溶液中的杂质,得到含杂量低的食品级浓缩磷脂。选择孔径1.2μm的膜在微滤压力0.15MPa、微滤温度50℃和料液比1∶4(W/V)下过滤磷脂溶液,一次微滤得率为82.3%。用二次微滤工艺,浓缩磷脂得率可以提高到92.5%,得到的食品级大豆浓缩磷脂的主要指标都达到美国同类产品标准。     

膜过滤法制备食品级浓缩磷脂

以粗大豆浓缩磷脂为原料,采用无机膜过滤方式制取高质量浓缩磷脂.研究了膜孔径、溶料比、膜过滤温度、物料流速和水分含量对膜通量、丙酮不溶物含量和磷脂得率的影响.实验结果表明,水分含量0.1%,膜孔径0.20μm,溶料比6:1,过滤温度50 ℃,物料流速3 m/s为最佳工艺条件.在最佳条件下,产品中丙酮不溶物含量可达到60%以上,最高可达65%以上;且乙醚不溶物含量可以稳定地控制在0.05%以下.     

混合油无机陶瓷膜微滤除杂制备食品级浓缩磷脂的研究

用2．4μm、3．0μm、4．2μm的无机陶瓷膜微滤除去大豆混合油中的杂质，此混合油经蒸发脱溶、水化脱胶、离心分离、浓缩干燥得到大豆浓缩磷脂的乙醚不溶物含量小于0．01％。同时研究了6号溶剂微滤膜通量和膜孔径及过滤压力的关系。结果表明：在过滤压力一定的情况下，溶剂的膜通量随着膜孔径的增大而增加。在0．30MPa过滤压力下，30％(V％)浓度的混合油微滤，其膜通量也随着膜孔径增大而增加。     

膜过滤生产食品级浓缩大豆磷脂过程中膜污染清洗方法

研究了膜法制备食品级浓缩磷脂过程中膜污染的清洗问题。实验研究了生产过程中正己烷溶剂溶清洗及重度污染后NaOH溶液清洗对无机膜的膜通量、产品丙酮不溶物含量的影响。实验结果表明,过滤过程中适时地用含水率低的正己烷清洗系统可较理想的延缓膜污染。对于重度膜污染,采用2g/dLNaOH溶液80℃清洗2h后用清水冲洗可使膜通量达到最优水平,产品丙酮不溶物含量超过质量分数60%。     

响应面试验优化藻类来源磷脂型DHA的提取工艺

采用低温脱胶法和膜分离技术提取DHA藻油中磷脂型DHA。在单因素试验的基础上,利用响应面试验优化磷脂型DHA提取工艺,得到最佳提取工艺条件为过膜压力0.29 MPa、膜孔径1.0μm、溶料比6∶1、过膜温度50℃。在最佳提取工艺条件下,制备的磷脂型DHA产品正己烷不溶物为0.028%,可以稳定地控制在0.03%以下;丙酮不溶物含量可达到61.3%;磷脂型DHA产品得率为80.8%,且磷脂中DHA含量在44%以上。     

鳀鱼蒸煮液陶瓷膜微滤浓缩的研究

本文研究了压力、温度、陶瓷膜孔径、蒸煮液浓度和投料方式对微滤浓缩鳀鱼蒸煮液膜通量的影响。微滤浓缩时,0.45 μm和0.14 μm陶瓷膜对蛋白质的浓缩效率相同,但选用0.14 μm陶瓷膜使整体膜浓缩效率提高;升高温度、压力等均能提高陶瓷膜通量;降低蒸煮液的浓度虽能增大陶瓷膜通量,但降低了蛋白质的浓缩效率。45 ℃浓缩时陶瓷膜通量较高,并且浓缩液的菌落总数、挥发性盐基氮（TVB-N）相对于浓缩因子的增长率最小,丙二醛（TBARS）的增长率与35 ℃、25 ℃相近。因此在温度45 ℃、压力0.3 MPa和选用0.14 μm陶瓷膜的条件下,采用间歇的投料方式作为陶瓷膜浓缩鳀鱼蒸煮液较优的操作条件。陶瓷膜清洗方面,复合清洗剂（1% NaOH+0.05% SDS）在45 ℃的清洗条件下,清洗40 min可使膜通量回复率达到98.99%,比单一清洗剂（1% NaOH）提高22.85%。     

陶瓷膜微滤生物柴油的研究

用孔径0.6、0.2、0.1μm陶瓷膜在进口压力0.26MPa、出口压力0.06MPa、温度60℃下微滤粗生物柴油除去其中的皂和游离甘油。结果表明,0.1μm的陶瓷膜滤过液中K、Na、Ca、Mg和游离甘油含量达到欧盟生物柴油标准(EN14214)。用孔径为0.1μm陶瓷膜微滤生物柴油,当浓缩比为4∶1时,膜通量为300L/(m2.h),得到总滤过液中的K、Na、Ca、Mg的含量分别为1.40、1.78、0.81、0.20mg/kg,游离甘油含量为0.0108%。     

乳酸杆菌无机陶瓷膜微滤浓缩条件的研究

采用无机陶瓷膜管微滤技术浓缩乳酸杆菌发酵液。实验中比较了不同膜管孔径、膜管面积、操作压力等对乳酸杆菌发酵液浓缩效果的影响。结果表明,选择无机陶瓷膜管孔径为0.1μm,膜面积为0.24 m2,操作压力为0.15 MPa,可得到体积浓缩5.6倍,活菌死亡比0.2,截留率达96%的乳酸杆菌浓缩液。无机陶瓷膜可用于乳酸杆菌发酵液的浓缩处理。     

膜分离技术纯化栀子黄色素的研究

以栀子黄色素萃取液为原料,研究陶瓷膜微滤过程中不同膜孔径、不同操作压力对渗透通量和色素液品质的影响,确定孔径200nm的陶瓷膜、0.125MPa压力下微滤为栀子黄色素纯化的最佳工艺条件。栀子黄微滤渗透液再经聚酰胺膜纳滤,1.5MPa压力下浓缩倍数达到3倍以上。     

芝麻油浓缩磷脂提取工艺条件的研究

以水代法和机榨法制取的芝麻毛油静置沉淀后的底部沉淀物（即芝麻油脚）为原料,利用正己烷萃取除杂、水化浓缩及絮凝分离的方法从中提取芝麻油浓缩磷脂,并对水化浓缩和絮凝分离的工艺条件进行了研究。结果表明：正己烷萃取除杂（条件为料液比1∶8、时间6 h、温度25℃）后芝麻油脚中固体不溶性杂质含量从21.25%降低至0.04%;水化浓缩的最佳条件为水与萃取除杂油脚质量比4.5∶1、水化时间40 min、水化温度85℃,水化浓缩后丙酮不溶物含量从3.41%提高至45.87%;絮凝分离的最佳条件为预热温度40℃、反应温度90℃、NaCl添加量3%、反应时间20 min,所得浓缩磷脂的丙酮不溶物含量为56.82%。     

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