反胶束法提取辣木籽蛋白工艺优化

以脱脂辣木籽粉为原料,利用反胶束法提取辣木籽蛋白并进行工艺优化。通过单因素实验和正交实验考察反胶束（AOT）质量浓度、提取温度、pH、料液比、水分活度（Wo）5个因素对提取辣木籽蛋白的反胶束前萃工艺的影响,再通过单因素实验和二次通用旋转实验考察提取温度、pH、KCl浓度、提取时间4个因素对提取辣木籽蛋白的超声波辅助反胶束后萃工艺的影响。结果表明：反胶束前萃最佳工艺条件为pH 9、料液比1∶ 50、AOT质量浓度0.08 g/mL、提取温度45 ℃、水分活度25,该条件下所得前萃辣木籽蛋白提取率为67.2%;超声波辅助反胶束后萃最佳工艺条件为提取时间45 min、提取温度45 ℃、pH 6.5、KCl浓度1.25 mol/L,在此条件下所得后萃辣木籽蛋白提取率为58.5%。     

反胶束法提取红芸豆蛋白的前萃工艺优化

采用二-（2-乙基已基）琥珀酸酯磺酸钠（AOT）-异辛烷-氯化钾组成的反胶束体系萃取红芸豆蛋白（RKBP）。采用电导法考察AOT浓度对AOT-异辛烷-水反胶束体系含水量和临界增溶水量的影响,确定反胶束体系稳定的AOT浓度范围。采用单因素实验分别研究了AOT浓度、缓冲液pH、KCI浓度和萃取时间等因素对RKBP前萃率的影响,通过正交实验优化前萃条件。结果表明,不同AOT浓度对应的反胶束体系的临界含水量值（Wc）基本一致,反胶束体系能够增溶的水的体积随AOT浓度的增加而明显增大,反胶束体系稳定的AOT浓度上限值为2mol／L。正交优化获得反胶束法萃取RKBP的最佳前萃条件为：AOT浓度1．25mol／L,缓冲溶液pH7．5,KCl浓度0．05mol／L,萃取时间90min。在该最优工艺条件下,RKBP前萃率达到43．57％。     

响应面法优化反胶束提取花生粕蛋白前萃工艺

采用二-(2-乙基已基)琥珀酸酯磺酸钠(AOT)-异辛烷-氯化钾组成的反胶束体系萃取花生粕蛋白质。研究了AOT浓度、KCl溶液pH、KCl溶液浓度、萃取时间、料液浓度、温度等因素对提取率的影响关系,在单因素基础上,通过响应面分析法确定前萃最佳工艺条件为AOT浓度0.06 mol/L、KCl溶液p H 8.15、KCl溶液浓度0.1 mol/L、萃取时间60 min、料液浓度10 g/L和温度37.40℃,在此最佳工艺条件下,花生粕蛋白前萃率为61.2%。     

超声波辅助SDS反胶束体系前萃米糠蛋白的工艺研究

利用超声波辅助SDS(十二烷基磺酸钠)/异辛烷-正辛醇反胶束体系萃取米糠蛋白。主要考察了料液比、SDS质量浓度、W_O值、超声功率、前萃时间、增溶水p H和KCl浓度对米糠蛋白前萃率的影响。通过正交实验设计优化得到超声波辅助最佳萃取工艺条件为料液比0.015∶1、SDS质量浓度0.08 g/m L、W_O值30、超声功率225 W、前萃时间40 min、增溶水p H 7.5和KCl浓度0.25 mol/L。在最佳条件下,米糠蛋白前萃率为86.96%,比常规振荡萃取的高17.14个百分点。     

酶法辅助反胶束前萃取核桃蛋白的研究

在传统利用反胶束萃取核桃粕中的蛋白质的基础上,添加辅助酶萃取,此方法综合了反胶束与酶法技术的双重特征及优势。试验通过在反胶束体系中添加酶,并调节体系单因素含水量(W0)、缓冲液p H、萃取温度、萃取时间条件下测定反胶束对蛋白前萃率的影响,通过主要因素的正交试验,优化提取参数,在酶添加量为4%、p H10、萃取温度55℃、反胶束含水量W0为18、萃取时间为100 min条件下,蛋白前萃率为83.29%。SDS-PAGE电泳图像直观地呈现出酶法辅助反胶束萃取得到的核桃蛋白亚基条带及含量都普遍较单纯反胶束萃取蛋白的高。     

反胶束降系萃取葵花籽仁中蛋白质的研究

对AOT/异辛烷反胶束溶液萃取技术从葵花籽粉中提取蛋白质的前萃工艺进行了研究.控制体系含水量W0,使绿原酸先萃取出,然后分析了各因素对蛋白质萃取率的影响,并正交实验分析得出最佳优化前萃工艺条件为:AOT0.12g/mL,料液比1:25,含水量W0为18,增溶水pH7.0,温度40℃,时间60min,KCl 0.05mol/L.     

超声波辅助AOT反胶束体系后萃大豆蛋白的研究

研究超声波辅助反胶束体系(AOT/异辛烷)萃取大豆蛋白的后萃过程,并分析各因素对蛋白后萃率的影响,通过正交试验得到了AOT/异辛烷反胶束体系萃取全脂大豆粉中蛋白的最佳后萃工艺条件为:KCl浓度1.0 mol/L、pH值7.0、超声功率为270 W.在此条件下,蛋白质的后萃率为98.91%.     

反胶束法萃取蒜氨酸前萃工艺的优化

采用由十六烷基三甲基溴化铵(CTAB)-正庚烷-正辛醇和氯化钾缓冲溶液组成的反胶束体系从大蒜粉中提取蒜氨酸,考察了CTAB浓度、萃取时间、KCl浓度、温度、缓冲溶液pH值、蒜粉加入量对蒜氨酸前萃提取率的影响,并在单因素基础上,通过正交实验确定前萃最佳工艺条件:CTAB浓度0.07mol/L,缓冲溶液pH 7.0,KCl浓度0.3mol/L,萃取时间30min,加入蒜粉含量0.5g/30mL,温度40℃,在此最佳工艺条件下,蒜氨酸前萃提取率达到1.62%。     

反胶束溶液萃取杏仁蛋白前萃工艺的研究

对AOT/异辛烷反胶束溶液萃取杏仁蛋白的前萃工艺进行了研究。试验以AOT/异辛烷为反胶束溶液体系,以蛋白质萃取率为指标,分别对溶液的pH值、W0值、萃取时间和萃取温度进行了单因素试验以及四因素三水平的正交试验,以确定杏仁蛋白前萃的最佳工艺。正交试验结果方差分析表明,在各因素中,W0值对蛋白质提取率影响达到显著水平,其他三因素未达到显著水平,确定的最佳工艺条件为:W0值为40,溶液pH值7.0,前萃温度25℃,前萃时间90 min。     

超声辅助SDS反胶束反萃取花生蛋白的工艺研究

研究采用十二烷基磺酸钠(SDS)/异辛烷—正辛醇反胶束体系反萃取花生蛋白,并采用超声波辅助萃取,主要研究了缓冲溶液pH值、萃取时间、萃取温度、超声功率、KCl浓度对花生蛋白后萃率的影响.试验结果表明最佳后萃工艺条件为:缓冲溶液pH值为9、萃取时间为40 min、萃取温度为45℃、超声功率270 W、KCl浓度为1.5 mol/l,此时蛋白后萃率为82.62％.     

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.     

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.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

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.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

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