国产小麦品种麸皮结构层的定性和定量分析方法

选取6种代表性中国小麦,对麦麸结构层进行手工剥离、显微观测和特征组分分析,从而建立国产麦麸结构层的定性和定量分析方法。结果表明,国产小麦中麸皮的平均比例为18%,外果皮、中间层和糊粉层分别占22%、31%和47%;通过光学和荧光显微镜可定性判定麦麸结构层;麦麸中间层中烷基间苯二酚(ARs)的含量达11.9 mg/g,分别是外果皮和糊粉层中含量的110倍和230倍,而糊粉层中总磷的平均含量为28.7 mg/g,超过外果皮和中间层中含量的20倍。因此,ARs和磷可分别作为中间层和糊粉层的标示物,外果皮可通过计算获得。结合显微观测和标示物定量的方法,可实现全麦产品中麦麸及其结构层的添加量的快速分析。     

小麦麸皮结构层干法分离的初步研究

研究了干法分离麦麸结构层。首先对小麦麸皮进行微粉碎,通过粒径分析出麦麸粉体的粒径分散性最好的粉碎时间,利用旋振筛对此时的麦麸进行筛分,得到粒径不同的4种麦麸粉体,然后对各个麦麸粉体进行荧光定性和生化标示物定量研究。结果表明,筛分后,外皮层和中间层集中在200目筛上物的麦麸中,约占78.9%,麦麸糊粉层的细胞壁主要集中在200目筛下物和325目筛上物中,比例达41.7%,而小颗粒的麦麸糊粉层细胞内容物则集中在325目筛下物。研究初步表明,通过微粉碎和筛分的方法可以对不同麦麸结构层进行富集,为麦麸的深加工提供了一种简单的干法分离途径。     

微粉碎对燕麦麸皮营养成分及物理特性的影响

以燕麦麸皮为原料,研究了微粉碎对麸皮营养成分及物理特性的影响.结果表明微粉碎可以提高燕麦麸皮总膳食乡维含量,但对麸皮蛋白质、脂肪、水分及灰分含量影响不大;微粉碎还可以改善燕麦麸皮的物理特性,在粒度为250～125μm时燕麦麸皮持水力最强;在180～150 μm时麸皮膨胀力最大;在150～125μm时麸皮水溶性最佳.     

酶法制备小麦麸皮戊聚糖的研究

采用α-淀粉酶和碱性蛋白酶分别降解小麦麸皮中的淀粉和蛋白质成为可溶性组分,通过水洗过滤分离将其除去,以制得小麦麸皮戊聚糖。在淀粉的分离提取中,通过实验分析得出最佳参数为:料液比1:12(g/ml)、加酶量0.08g、酶解时间25min、酶解温度95℃。小麦麸皮中淀粉的含量从18.6%降至0.5%以下。在蛋白质的分离提取中,通过实验分析得出最佳参数为:酶解时间4h、酶解温度40℃、固液比5%(g/ml)、加酶量1.0%。酶解后小麦麸皮中蛋白质残留量仅为0.62%。经过去淀粉和蛋白质的小麦麸皮中戊聚糖含量为34.51%。     

不同来源小麦麸皮营养成分及酚类物质含量的比较

本文收集国内9个小麦主产省12个小麦麸皮样品,对蛋白质、总淀粉、脂肪、膳食纤维和戊聚糖,及不同形态酚类物质(游离型、可溶共价结合型、束缚型)等组分含量进行测定,采用数学统计方法对样品间组分差异和各组分相关性进行统计分析。结果表明:麸皮三大主要营养成分总膳食纤维、蛋白、总淀粉平均含量分别为47.30、19.85和16.90%,总淀粉和膳食纤维变幅较大,变异系数(CV)分别达到19.94和8.75%,蛋白变幅较小,CV值仅为3.16%,戊聚糖作为麸皮中主要膳食纤维,平均含量达到31.57%;总酚含量4470.37~5521.30μg GAE/g,73.9~79.1%为束缚型酚酸;束缚型阿魏酸在单体酚中占主导地位,含量高达2677.4~3401.8μg/g;,以下组分间存在极显著相关性(p0.01),其中膳食纤维及碱解束缚型酚酸(BBPA)与总淀粉呈极显著负相关,戊聚糖及BBPA与膳食纤维极显著正相关,戊聚糖与BBPA极显著正相关,酸解束缚型酚酸(ABPA)与总酚极显著正相关。     

丝状真菌发酵小麦麸皮中酚类物质抑制胰脂肪酶活性和HepG2细胞内甘油三酯沉积的作用

探讨了2种食品加工中常用的丝状真菌(米根霉和米曲霉)固态发酵小麦麸皮后,其总酚含量的变化,研究了发酵前后小麦麸皮中酚类物质对脂肪酶活性和Hep G2细胞内甘油三酯沉积的抑制作用。结果表明:发酵能显著提高小麦麸皮的总酚以及其抗氧化性(P0.05)。发酵后的小麦麸皮酚类物质抑制胰脂肪酶以及Hep G2细胞内甘油三酯沉积的活性均显著增强(P0.05)。未发酵、米根霉和米曲霉发酵的小麦麸皮乙酸乙酯萃取物抑制胰脂肪酶活性的IC50值分别是1.35、0.78和0.85 mg/m L。在90μg/m L质量浓度条件下,未发酵、米根霉发酵和米曲霉发酵小麦麸皮的乙酸乙酯组分对Hep G2细胞内甘油三酯沉积的抑制率分别为14.4%,26.2%和20.5%。     

响应面法优化小麦麸皮中总酚含量的测定

响应面法优化小麦麸皮中总酚含量的测定,主要考察的因素有筛分孔径、福林试剂含量、Na_2CO_3质量分数和反应温度。450~900 nm波长扫描结果确定750 nm作为多酚含量检测波长。单因素试验及响应面试验结果表明:各个单因素对总酚含量的影响从大到小的顺序依次为福林试剂含量、筛分孔径、反应温度、Na_2CO_3质量分数;小麦麸皮中总酚含量测定的最佳条件为筛分孔径9.23XX、福林试剂含量5.39 m L、Na_2CO_3质量分数14.24%、反应温度29.36℃。在此条件下,测定的小麦麸皮中总酚含量为2.044 81 mg/g。     

冲击粉碎米糠的成分变化研究

采用机械冲击粉碎对米糠进行粉碎、分级，米糠超微粉平均粒径达到7μm 以下，细胞充分破壁；并分析了其成分蛋白质、氨基酸、V_(B1)和 V_(B2)含量的增加，膳食纤维含量减少的机理。对现有的几种膳食纤维测量方法做了对比讨论。     

牡蛎壳超微粉碎工艺及粉体性质

为了探索钙添加剂的超微粉碎加工工艺及粉体性质,将牡蛎壳清洗、干燥、初步粉碎后进行超微粉碎.确定牡蛎壳超微粉碎的最佳工艺参数为:进料速度0.0625g/s,气流压力:进料压力、粉碎压力为0.56MPa,进料粒度150μm,粉碎一次.由超微粉碎得到的粉体,更易溶解于水,而且在水中的分散速度更快.     

小麦麸皮加工成食品的探讨--麸皮面粉、糊粉层面粉

介绍了发达国家低碳面粉(低碳水化合物面粉)的产生和市场的形成。探讨了可作为低碳面粉组合的麸皮面粉的制作工艺、设备。阐述了小麦籽粒的组成,减少小麦面粉碳水化合物含量的方法,麸皮面粉的主要质量指标:细度、色泽、卫生和口味;麸皮水热处理、研磨、筛分、细度测量和低碳面粉、全麦面粉的配制;从红麦麸皮提取糊粉层、微研磨和配制高蛋白面粉的方法。最后提出新产品应进行制作食品试验。     

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