桑椹籽油的提取及其脂肪酸组成分析

以桑椹籽为原料,通过单因素试验、正交试验研究了漫提溶剂、料液比、浸提温度、浸提时间等因素对桑椹籽油提取率的影响,确定了溶剂浸提桑椹籽油的最佳工艺条件,并采用气相色谱对桑椹籽油的脂肪酸组成进行了分析.结果表明,各影响因素的主次顺序为:浸提温度>料液比>浸提时间;溶剂提取桑椹籽油的最佳工艺参数为:石油醚为提取剂,浸提温度为40℃,浸提时间5 h,料液比(g·mL-1)为1 10.在此条件下,桑椹籽油的提取率为28.62%;桑椹籽油中总不饱和脂肪酸含量为84.59%,其中亚油酸含量高达74.86%.     

溶剂法浸提玉米纤维油的工艺研究

以脱淀粉玉米纤维为原料,采用溶剂法浸提玉米纤维油。以纤维油提取率为指标,在单因素试验的基础上,以正己烷为浸提溶剂,选取料液比、浸提时间、浸提温度为影响因素。通过正交试验优化玉米纤维油浸提工艺。结果表明玉米纤维油的最佳浸提工艺为:提取溶剂为正己烷,料液比为1∶16(g/m L),浸提时间为60 min,温度40℃,此时玉米纤维油的提取率为82.58%。     

乙醇法提取黑胡椒油树脂的研究

设计正交试验研究乙醇法提取黑胡椒油树脂的工艺条件,考查了乙醇浓度、料液比、浸提温度、浸提时间以及原料粒度对黑胡椒油树脂提取率的影响。试验结果表明：在乙醇浓度为85％,原料粒度为80目,料液比为1：10（g／mL）,浸提时间为3．5h,浸提温度为65℃工艺条件下,黑胡椒油树脂提取率为10．32％。     

水酶法提取番木瓜籽油工艺及其氧化稳定性分析

以番木瓜籽为原料,通过单因素试验和正交试验研究不同酶种类、酶解时间、料液比、酶添加量、酶解温度等因素对番木瓜籽油提取率的影响,确定番木瓜籽油提取的最佳工艺条件,并以番木瓜籽油过氧化值为评价指标,考察温度、光照、抗氧化剂对番木瓜籽油氧化稳定性的影响。结果表明,番木瓜籽油的最佳提取条件为：选用中性蛋白酶,酶添加量2.5%、酶解时间5 h、料液比1∶7、酶解温度45 ℃。在此条件下,番木瓜籽油的提取率为85.73%。温度、光照、氧气均会引起贮藏过程中番木瓜籽油过氧化值的升高。添加抗氧化剂可明显提高番木瓜籽油的氧化稳定性,其中叔丁基对苯二酚的抗氧化效果最好。     

山竹壳中原花青素提取分级及抗氧化活性的研究

从提取溶剂及提取条件等方面对山竹壳中原花青素提取工艺进行优化研究。通过提取溶剂、提取温度、提取时间、料液比、乙醇溶液酸碱度5个单因素试验，采用响应面分析法，分析乙醇溶液酸碱度、浸提时间、浸提温度和料液比之间的交互作用以及对原花青素提取率的影响，建立数学模型，得出最佳工艺条件为乙醇浓度的体积分数为60％，浸提温度60℃，浸提时间66min，料液比1：19，乙醇溶液的酸碱度为3．7，原花青素提取率质量分数为5．94％。同时采用不同有机溶剂分级山竹壳提取液，测定不同溶剂相自由基的清除率。     

谷精草黄酮类化合物的提取工艺研究

以乙醇为浸提溶剂,从谷精草中提取黄酮类化合物,通过单因素实验和正交实验,考察乙醇浓度、料液比、浸提时间、浸提温度对谷精草黄酮提取率的影响.结果表明,各因素的影响程度依次为:乙醇浓度>浸提时间>浸提温度>料液比;提取的最佳工艺条件为:60%乙醇,料液比1:25,提取时间3h,浸提温度70℃,在此条件下,谷精草黄酮提取率为4.95%.     

复合溶剂提取大蒜精油的工艺条件研究

以环已烷- 丙酮复合溶剂提取大蒜精油,对复合溶剂提取大蒜精油的工艺条件进行研究,探讨影响大蒜精油得率的因素条件：复合溶剂质量配比、料液质量比、浸提温度、浸提时间。单因素试验确定较好的因素水平,正交试验确定最佳提取工艺条件。结果表明,提取大蒜精油最佳工艺条件为：环已烷- 丙酮复合溶剂质量配比7:3,料液质量比1:6,浸提温度55℃,浸提时间6h。     

茎瘤芥叶叶绿素提取工艺研究

以茎瘤芥叶为原料,采用冷冻干燥技术对叶片进行预处理后,采用单因素试验和正交试验研究不同的浸提剂、乙醇浓度、料液比、浸提温度和浸提时间对茎瘤芥叶叶绿素提取率的影响,并优化茎瘤芥叶叶绿素提取工艺.结果表明:有机溶剂提取茎瘤芥叶叶绿素优化工艺为料液比1∶50,提取溶剂为乙醇体积分数70％的乙醇/丙酮溶液,50℃水浴温度浸提3h,叶绿素提取率为1.08％.     

油茶压榨饼粕残油浸提工艺优化

以油茶籽压榨后的饼粕为原料,采用有机溶剂法对其残留茶油进行浸提,并对浸提工艺进行研究。通过单因素试验重点探讨溶剂、料液比、浸提温度、浸提时间等因素对油茶饼粕残油提取率的影响,并采用正交试验确定最佳浸提工艺条件。结果表明,油茶饼粕采用石油醚作为浸提溶剂,在提取温度60℃、料液比1∶8(m∶V)、提取时间7h的浸提条件下,油茶压榨饼粕残油提取率可达8.72%。     

荔枝果肉多酚的提取与分离

以荔枝果肉为试验材料,以多酚含量为评定参数,提取分离其中的多酚物质。以乙醇溶液为提取溶剂,通过单因素试验和正交试验,考察了浓度、提取时间、料液比、提取温度、浸提次数等影响提取率的几个重要因素,得出影响果肉中多酚提取的因素由大到小依次为,提取时间料液比乙醇浓度提取温度,最佳工艺条件为,乙醇浓度70%,料液比1∶11,浸提时间6 h,浸提温度40℃,浸提2次,而且荔枝果肉多酚主要以多酚的多聚体为主,其次是低聚体和单体。     

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