马铃薯淀粉改性及其吸附茶多酚的条件优化

以马铃薯淀粉为原料在70℃、40～44 s条件下制备改性淀粉,考察温度、pH、茶多酚浓度和吸附时间对原淀粉和改性淀粉吸附茶多酚的影响。根据单因素试验结果,设计正交试验,确定吸附茶多酚的最优工艺条件为:原淀粉温度20℃、pH 3.0、茶多酚浓度16 mg/mL和吸附时间120 min,茶多酚吸附量为113.5mg/g;改性淀粉条件为温度25℃、pH 2.0、茶多酚浓度28 mg/mL和吸附时间80 min,茶多酚吸附量为301.1mg/g。在最优条件下改性淀粉吸附茶多酚量为原淀粉的2.65倍,为制备富含茶多酚的淀粉质材料提供技术指导。     

响应面超声波法提取藤茶多酚工艺优化

为提高得率,采用超声波法提取藤茶多酚。以藤茶多酚得率为评价指标,在单因素试验的基础上,设计Box-Behnken响应面试验优化提取工艺。结果表明:藤茶多酚最佳工艺条件为超声功率300 W、超声温度50℃、超声时间25 min、乙醇体积浓度60%。在此工艺条件下,茶多酚得率为614.64 mg/100g。     

竹叶中活性茶多酚成分的提取研究

探讨用超声技术从竹叶中提取茶多酚的最优工艺条件。以茶多酚的产率为考察指标,在单因素试验的基础上,固定超声功率为70 W,采用L9(34)正交试验来确定浸提温度、超声时间、料液比、乙醇体积分数四个因素的最佳组合。结果表明,在超声功率为70 W的前提下,从竹叶中超声提取茶多酚的适宜工艺条件为:浸提温度75℃,超声时间40 min,料液比1∶20(g/mL),乙醇体积分数75%,此条件下茶多酚提取产率为0.624 3%。该提取工艺稳定可靠、环保,具有使用价值。     

正交优化微波醇提茶多酚的工艺

对微波提取工艺方法进行改进,进一步优化了微波提取茶多酚的提取工艺。结果表明,提取茶多酚的最佳工艺条件为:以50%的乙醇溶液作为提取剂,料液比1∶10(g/mL),微波功率320 W,浸提时间20 s,经两级提取,结果可达82.6%。     

茶多酚脂质体的制备

以包封率作为考察指标,对茶多酚脂质体的制备方法进行了筛选,通过二次回归旋转组合设计优化出了茶多酚脂质体制备工艺及配方.研究结果表明,逆相蒸发法制备茶多酚脂质体所得到的包封率最高,采用此方法优化出的最佳配方为:SPC/CH(W/W)3:1、茶多酚浓度为7mg·mL-1、有机相/水相(V/V)为4:1、磷酸盐缓冲液的摩尔浓度为15mmol/L,在该配方下,数学回归模型预测的包封率为50.37%.此法制备茶多酚脂质体操作简便,工艺简单可行,所得脂质体包封率较高.     

硬脂酰氯改性对茶多酚抗油脂氧化性能的影响

茶多酚的众多亲水性酚羟基使其难溶解于油脂而影响其对油脂的抗氧化效果,为提高茶多酚抗油脂氧化性能,采用硬脂酰氯对其改性,以茶多酚与硬脂酰氯的摩尔配比、催化剂用量和反应温度为实验因素,以添加改性茶多酚的油脂经高温氧化后的POV为考察指标,采用响应曲面法优化工艺条件,并采用红外、紫外光谱表征分子结构,结果表明:反应温度与硬脂酰氯添加量对POV有显著交互作用(P<0.05),即反应温度的临界值随硬脂酰氯添加量升高呈线性增加趋势;最佳工艺下油脂POV为5.711meq/kg,比对照组(添加普通茶多酚)降低33.9%;改性后出现亚甲基和直链脂肪基团的特征吸收峰,说明硬脂酰氯与茶多酚的酚羟基形成酯化交联,改善了茶多酚亲脂性,从而显著提高茶多酚抗油脂氧化效果。     

超声波辅助提取安化黑茶中茶多酚的工艺研究

为了探索超声波辅助法提取安化黑茶茶多酚的工艺条件,以乙醇为溶剂,利用正交试验法优化茶多酚的提取工艺。结果显示,当超声功率为100 W时,安化黑茶茶多酚提取的最佳工艺参数为料液比1∶10(g/mL)、乙醇体积分数50%、提取温度70℃、提取时间60 min,超声波协助提取提高了茶多酚和儿茶素的提取效率,为安化黑茶精深加工提供了重要的理论依据。     

响应面法优化超声波辅助提取茶多酚的工艺研究

对茶叶多酚的超声波辅助提取,首先通过单因素试验选择影响因素与水平,然后在单因素试验的基础上采用四因素三水平的响应面分析法,依据回归分析确定较优的提取工艺条件.结果表明,其较优工艺条件为:提取温度为71℃,超声波处理时间为30min,超声波功率为800W,液料比为16:1(V/W).采用该工艺条件,茶多酚的浸出率达到22.89%.     

正交实验优化多频超声波辅助法提取绿茶茶多酚工艺

研究并优化多频超声辅助提取茶多酚的工艺。以绿茶为实验原料,研究提取时间、提取温度、料液比、循环速度、多频超声波功率5个因素对多频超声辅助提取茶多酚的影响。在此基础上利用正交实验对多频超声波提取工艺进行优化。多频超声辅助法提取绿茶茶多酚最佳工艺为:超声(28kHz,200W),(33kHz,200W),(40kHz,200W),(60kHz,200W),时间20min,温度65℃,料液比1∶70g/mL,循环速度1200r/min;提取率为25.69%,比传统浸提法提高了43.68%。     

茶多酚对棉织物的吸附及其抗菌消臭效果

为开发植物多酚保健功能纺织品,通过单因素分析法,探讨pH值、温度、处理时间对茶多酚在棉织物上吸尽率的影响;对棉织物进行阳离子改性,分析改性剂浓度、碱剂用量、改性温度和改性时间对吸尽率的影响;测试茶多酚整理后棉织物的抗菌消臭性能。结果表明：茶多酚对棉织物的浸渍优化工艺为茶多酚6%（o． w．f）,温度40℃,时间60min,浴比1：30,应用此工艺,茶多酚对棉织物的吸尽率为14.6%;棉织物的阳离子改性优化工艺为：改性剂质量浓度25 g/L,碱剂质量浓度6 g/L,温度70°C,时间90 min,浴比1：30,茶多酚应用此改性工艺处理的棉织物的吸尽率为48.8%。经阳离子改性和茶多酚二步法处理后,棉织物的抑菌率（金黄色葡萄球菌）和消（氨）臭率分别为92.2% 和90%,再经铜后媒处理,棉织物的抑菌率（金黄色葡萄球菌）和消（氨）臭率分别达100% 和99.9%。     

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