油茶饼粕中茶皂素的提取及H2O2法脱色条件研究

通过有机溶剂浸提,研究并确定了从油茶饼粕中提取茶皂素的最佳工艺：乙醇体积分数70％,料液比（g：mL）1：4,提取时间3h,提取温度75％2;H2O2法脱色的最佳条件为pH值8.5,脱色温度70℃,脱色时间2h,加入H2O2 25mL。在此条件下提取的茶皂素得率为17.2％,纯化后的茶皂素质量分数达到87.4％。     

茶皂素的提取过程中的色素抑制研究

茶皂素是一种优良的天然非离子表面活性剂，但提取过程中由于茶籽饼含有较多的氨基酸和还原糖，容易发生褐变，使产品的颜色较深从而限制了其用途，本文介绍了抑制提取过程中的美拉德反应的方法，以利于得到纯度较高的茶皂素颜色较浅的产品。     

几种茶皂素脱色工艺的研究进展

目前茶皂素主流生产工艺粗放,产品颜色深、纯度低,制约了其在高端领域的应用。本文论述了几种茶皂素脱色工艺的研究进展,以期为茶皂素的规模化生产提供参考。     

茶皂素脱色工艺研究

研究比较几种脱色剂对茶皂素脱色效果影响,结果表明双氧水用于茶皂素脱色效果较好,通过 正交试验得出其最佳脱色条件为:脱色温度70℃、脱色时间90 min、H2O2加入量为4％、溶液pH为 10。     

茶皂素还原脱色法初探

实验通过还原脱色方法对茶皂素溶液进行脱色研究,取得了较好的效果。实验确定了四个参数:两种脱色剂的使用量(KBH4和NaHSO3)、pH以及脱色温度。通过响应面进行优化,最终优化的结果为:两种脱色剂KBH4、NaHSO3的添加量分别为1.2%(w/w)和2.2%(w/w),pH为4.8,脱色温度为51.0℃,该优化条件下ΔE值为31.324±0.378,得率为95.8%。使用LC-MS/MS对脱色后的样品进行测定,结果表明还原脱色法对茶皂素结构没有影响。     

油茶茶籽壳中茶皂素分离纯化及结构分析的研究

以油茶茶籽壳为原料，采用乙醇提取法对其皂素类物质进行粗提取，HPD-100大孔树脂吸附法对茶皂素粗提物进行纯化，利用紫外光谱和超高效液相色谱-质谱法对纯化样品进行鉴定。实验结果表明，最佳提取工艺参数为：料液比1∶15,乙醇体积分数75%,提取温度70℃,提取时间120 min,其最高提取率达25.58%。粗提物经HPD-100大孔树脂纯化，30 mg/mL粗提液上样，水和20%乙醇洗去极性大的杂质，80%乙醇溶液洗脱出茶皂素，茶皂素纯化得率为48.63%,纯度提高1.38倍。该工艺操作简单，适合于茶皂素的分离。纯化茶皂素通过紫外光谱和液质联用检测，结果显示该样品为52种茶皂素单体的混合物并得到了其在质谱中的裂解规律。     

响应面法优化醇法提取茶皂素工艺研究

以无水乙醇为溶剂,对醇法提取脱脂油茶籽饼中茶皂素的工艺进行了研究.采用单因素实验考察了提取温度、提取时间、液固比对茶皂素得率的影响,并在此基础上采用响应面法对工艺条件进行了优化.结果表明最佳提取工艺条件为:提取温度77.0℃,提取时间1.5h,液固比5∶1.最佳条件下茶皂素得率为15.99％.     

橘皮残渣中水不溶性膳食纤维提取工艺研究

提取果胶和橙皮苷后残余的橘皮渣是一种极好的水不溶性膳食纤维来源。为了进一步实现对橘皮渣的二次利用,研究了采用化学方法从残余的橘皮渣中提取水不溶性膳食纤维(IDF)的提取工艺,同时对IDF的脱色工艺也进行了研究。结果表明,水不溶性膳食纤维最佳提取工艺条件是:NaOH浓度0.25mol/L、碱浸泡温度50℃、碱浸泡时间1.0h、固液比1∶15。膳食纤维脱色最优参数为:H2O2浓度为4%、脱色温度60℃、脱色时间3h、pH为9。在该条件下,不溶性膳食纤维产率为65.98%,提取率高达92.86%,产品颜色为乳白色。     

亚麻籽色素的研究

对亚麻籽色素的性质、提取、组成进行了研究，由颜色反应、紫外光谱初步确定了色素主要成分是异黄酮类或二氢黄酮类，并根据其性质提出了几种有效的脱色方法。     

响应面法对亚临界水提取茶枯饼中茶皂素的优化研究

研究亚临界水提取法提取茶枯饼中茶皂素的工艺条件,以茶皂素提取率为指标,在单因素试验的基础上利用Box-Behnken进行响应面优化。建立各因素与响应值之间的数学模型,确定亚临界水提取法的可行性及最佳工艺条件。结果表明,亚临界提取最佳工艺条件为:反应温度110℃,时间24 min,料液比1︰30 g/mL,在此条件下,茶皂素提取率为27.72%,与预测值27.35%的吻合度达98.66%。结合扫描电镜结果,得出亚临界水提取法是一种高效、经济、绿色环保的茶皂素提取方法。     

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