番木瓜籽蛋白质的提取工艺及其功能性质

以番木瓜籽为原料,经脱脂以酸沉碱溶法提取其中的蛋白质,并研究其乳化、起泡等功能性质。结果表明,最佳的提取工艺条件:料液比1∶40,p H为9.3,温度50℃,碱提时间120 min时最高提取率达到48.53%。番木瓜籽蛋白质的乳化性及稳定性随着蛋白质的浓度升高而升高,在p H3时最小,其乳化性在Na Cl浓度为0.2%时最大,而稳定性呈下降趋势;起泡性及稳定性随蛋白浓度升高而升高,在p H3.0,其起泡性和泡沫稳定性最小,在离子浓度(Na Cl)为0.2 mol/L时,其起泡性和泡沫稳定性最高。可见,此提取工艺效果较好,能将部分番木瓜籽蛋白质提取出来;番木瓜籽分离蛋白质乳化性和起泡性良好,这为番木瓜籽蛋白质的开发利用提供参考依据。      

蒸汽爆破辅助提取油茶籽蛋白及其功能性质分析

研究了蒸汽爆破结合碱溶酸沉法提取油茶籽蛋白工艺,确定了最佳提取条件,同时分析了pH、蛋白质量浓度、NaCl浓度和蔗糖浓度对蒸汽爆破处理前后油茶籽蛋白功能性质的影响。结果表明:最佳提取条件为蒸汽爆破压力0. 8～2. 3 MPa、蒸汽爆破时间30～120 s、料液比1∶10、提取温度40℃、pH 10、提取时间50 min,在此条件下,油茶籽蛋白提取率为71. 01%,显著高于未经蒸汽爆破处理的58. 74%;经蒸汽爆破处理得到的油茶籽蛋白吸油性和吸水性均有所提高; pH、蛋白质量浓度、NaCl浓度均对油茶籽蛋白的起泡性和泡沫稳定性、乳化性和乳化稳定性有不同程度的影响;蔗糖浓度对油茶籽蛋白起泡性作用比较明显,但对泡沫稳定性无显著改善作用,对乳化性、乳化稳定性起到改善作用。     

油茶籽粕蛋白质提取工艺及功能特性研究

以油茶籽粕为原料,采用碱溶酸沉法提取油茶籽粕中的蛋白质,运用正交试验方法确定最佳提取工艺条件,并与大豆分离蛋白的功能性进行比较研究。结果表明:当料液比1∶20,pH值8.0,浸提时间130 min,浸提温度60℃时提取效果最好,蛋白提取率可达48.59%;油茶籽蛋白的吸油性、乳化稳定性和起泡性优于大豆分离蛋白;而大豆分离蛋白的吸水性、乳化能力和泡沫稳定性优于油茶籽蛋白。     

沙棘籽粕蛋白的功能性质研究

以沙棘籽粕为原料,采用碱提酸沉法制备沙棘籽粕蛋白,并对其溶解性、水合能力、吸油能力、乳化性和乳化稳定性、起泡性和泡沫稳定性等功能性质进行研究.结果表明:沙棘籽粕蛋白的功能性质受pH、温度、盐离子浓度等环境因素影响大,在等电点pH 5.0附近时功能性质数据均最低.     

牡丹籽蛋白的制备工艺优化及功能性质评价

以脱壳后经超临界CO2萃取脱脂的牡丹籽粕为原料,采用碱溶酸沉法提取其中的蛋白质,在单因素试验的基础上,利用响应面法进行优化,确定提取牡丹籽蛋白的最佳工艺条件,并对提取的牡丹籽蛋白与大豆分离蛋白的一些功能性质进行比较研究。结果表明,牡丹籽蛋白的最佳提取工艺条件为:料液比1∶25,浸提p H 9.25,提取温度53.32℃,提取时间68.74 min,且影响因素主次顺序为浸提p H料液比提取时间提取温度;最佳工艺条件下的蛋白质提取率为62.95%,提取的牡丹籽蛋白中蛋白质含量为68.06%;牡丹籽蛋白的乳化稳定性和泡沫稳定性优于大豆分离蛋白,而其吸水性、吸油性、持水性、乳化性和起泡性却不如大豆分离蛋白。     

萝卜籽蛋白提取及其功能性质研究

以萝卜籽为原料,用正己烷脱脂得萝卜籽粕,采用碱溶酸沉法对萝卜籽粕中的蛋白质进行提取,并测定其等电点。通过考察料液比、碱溶p H、浸提时间和浸提温度对萝卜籽蛋白提取率的影响,确定最佳的萝卜籽蛋白提取条件,并对所提取的萝卜籽蛋白和大豆分离蛋白进行功能性质的对比。结果表明:萝卜籽蛋白溶解度为84.9%,有很高的营养价值;在料液比1∶20、碱溶p H 9.0、浸提时间120 min、浸提温度50℃的条件下,萝卜籽蛋白提取率为52.3%;萝卜籽蛋白等电点有两个,分别为p H 0.5和p H 4.5;萝卜籽蛋白吸油能力为328.67%,乳化性及乳化稳定性与大豆分离蛋白相近,起泡性及泡沫稳定性较大豆分离蛋白好。     

杏鲍菇蛋白质提取及功能性质测定

以杏鲍菇副产物为原料,通过干燥、粉碎、碱提、酸沉、回调、冻干等工艺提取杏鲍菇蛋白质。研究了pH值、固液比、提取温度和提取时间等单因素对蛋白质提取率的影响,并经正交试验优化提取工艺条件,分析了杏鲍菇蛋白的等电点、溶解度、吸油性、吸水性、起泡性和起泡稳定性以及乳化性和乳化稳定性。结果表明:杏鲍菇蛋白质适宜提取工艺条件为pH值11.0、固液比1:40(g/mL)、提取时间40 min、杏鲍菇蛋白质提取率为(42.37±1.63)%、纯度(63.4±0.87)%。     

菠菜叶蛋白功能特性的研究

采用碱提酸沉法制备出菠菜叶蛋白,对菠菜叶蛋白的某些功能性质进行了研究,着重探讨了环境因素如离子强度、蔗糖浓度、pH值、温度、浓度与菠菜叶蛋白的溶解度、吸水性、吸油性、乳化性与乳化稳定性以及起泡性与起泡稳定性的关系,为菠菜叶蛋白在食品工业中的应用奠定了一定的理论基础。     

榛子分离蛋白提取及其功能特性的研究

以低变性榛子饼为原料,经脱脂后采用碱提酸沉法提取榛子分离蛋白,确定了最佳提取工艺条件,并分析了榛子分离蛋白的功能特性.结果表明,提取榛子分离蛋白的最佳工艺条件为:料液比1:15,碱提pH9.0,碱提温度50℃,碱提时间70 min,酸沉pH4.5.最佳条件下榛子分离蛋白的溶解性、持水性和吸油性分别为34.0%、2.6 mL/g和2.15 mL/g,乳化性、乳化稳定性、起泡性和泡沫稳定性分别为61.2%、85.0%、86.5%和24.0%,榛子分离蛋白的等电点为4.52.     

脱脂猕猴桃籽粕蛋白质提取工艺条件研究

以脱脂猕猴桃籽粕为原料,采用单因素实验和正交实验,对碱提酸沉法提取脱脂猕猴桃籽粕蛋白的工艺条件进行探讨。结果表明,提取猕猴桃籽蛋白质优化工艺条件为：料液比1：25,浸提液pH9,浸提温度35℃,浸提时间40min。在此条件下,蛋白提取率可达87.08%。经测定,所得产品蛋白质泡沫稳定性为6.33%,起泡性49%,乳化性21.18%,持水性4.1,等电点pI4.2。     

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