介质对超高压改性玉米淀粉的影响

分别选用浓度为5%(w/v)的蔗糖、CaCl2、Na2HPO4和NaCl溶液作为淀粉悬浮介质,在570MPa压力下对5%(w/v)的玉米淀粉悬浮液进行高压处理5min,应用偏光显微镜和X-射线衍射仪检测所得样品的结晶性能和结构变化,结果表明:介质对玉米淀粉结构的影响能力从大到小的顺序为5%蔗糖>5% Ca-Cl2>5% Na2HPO4>5% NaCl;5% CaCl2和5% NaCl可以提高处理后的淀粉的结晶度。     

联合开发玉米饴糖 提高增值效益

为充分发挥本地玉米资源优势，利用玉米联产加工生产能力与糖果厂联合开发玉米治糖，提高了玉米增值率。1玉米是加工抬粮的优质原料1．1玉米的组成成份因品种、品质和成熟度不同各异，一般来说，玉米的主要成分是：淀粉60％～70％、糖1．5％～2．0％、蛋白质10％、油脂4．5％～55％、水分14％、纤维素3．0％、灰分1．5％，及其矿物元素。1．2玉米各部位生物化学成份：玉米籽粒不同部位的化学成份（每部分干物质的％）1．3玉米的不同品种与玉米生物化学的关系：（1）黄玉米的淀粉含量为65％～70％；（2）白玉米的淀粉含量为55％～65％；（3）…     

松仁玉米香肠的研制

目的与方法：以猪肉、松仁、玉米等为主要原料，生产松仁玉米香肠的工艺；通过预试验确定影响松仁玉米香肠质量的主要因素有松仁添加量、玉米添加量、肥肉和瘦肉的比例及淀粉添加量。采用正交试验，确定最佳配方；结果：最佳配方为松仁添加量2．5％、玉米添加量2．5％、肥瘦肉比例2：8、淀粉添加量13％。     

硫酸钠保护法制备非晶颗粒态玉米淀粉

硫酸钠具有抑制淀粉颗粒糊化的特性,可以在碱处理制备非晶颗粒态过程中抑制淀粉颗粒的膨胀。将玉米淀粉在按不同的比例的氢氧化钠和硫酸钠混合溶液在室温下处理,用偏光显微镜观测处理后的淀粉颗粒结构变化。结果表明：当质量分数3％的氢氧化钠溶液和质量分数为15％的硫酸钠溶液等体积使用时,可以制备出较好的非晶颗粒态玉米淀粉。     

氯化钠对玉米淀粉冻融稳定性的影响

对NaCl对玉米淀粉冻融稳定性的影响进行了研究。采用差示扫描量热仪(DSC)、扫描电子显微镜(SEM)和质构仪(TPA)等现代分析仪器分别研究不同摩尔浓度的NaCl对淀粉糊凝胶冻融析水率、超微结构、回生热力学特性以及质构的影响,并通过zeta电位分析仪探讨了盐离子与淀粉分子间的相互作用。结果表明:NaCl可降低玉米淀粉的析水率,减小淀粉凝胶结构的破裂;经过5次冻融后的玉米淀粉凝胶硬度和回生率均与NaCl溶液浓度呈显著负相关;NaCl的添加使得体系zeta电位下降,证明Na+与淀粉分子间存在相互作用,进而抑制冻融过程中淀粉的回生。     

糯玉米皮渣中膳食纤维的提取、纯化及理化性质研究

以糯玉米皮渣为原料，通过化学试剂结合酶法及无水乙醇来除去其中的淀粉、蛋白质、脂肪和蜡质，从而得到较纯净的膳食纤维；同时，测定了膳食纤维在不同的温度、pH值以及不同的时间下的膨胀性和持水力；测定了水溶性膳食纤维在25％的蔗糖液和10％NaCl溶液以及不同温度下的流变性。结果表明：膳食纤维总得率为62.0％；温度越高膨胀性越高，持水力也相应增高；pH值对其膨胀性也有一定影响，持水力出现高峰在pH8．0；当时间大于等于2．0h后，膨胀性和持水力几乎无变化；蔗糖溶液及NaCl溶液对流变性有一定的影响，随着温度的升高，其粘度逐渐下降。     

复合酶水解玉米皮制备阿魏酸和低聚糖的研究

研究采用阿魏酸酯酶、阿拉伯木聚糖酶、纤维素酶和Viscozyme L（戊聚糖复合酶）共同作用于去淀粉玉米皮，制备阿魏酸和低聚糖。结果表明，当混合酶制剂（阿魏酸酯酶和阿拉伯木聚糖酶）的添加量与底物干重比为6：1、纤维素酶和Viscozyme L的添加量均为底物干重的5％时，在pH5．5，45℃下酶解24h，能得到最高的阿魏酸和低聚糖产量；在此条件下能释放出去淀粉玉米皮中25．4％的阿魏酸和30．0％（以还原糖计）的低聚糖。     

复合变性淀粉提高鸡胸肉保水率的研究

报道了利用复合变性淀粉提高鸡胸肉保水率的研究。通过单因素实验，分别研究了磷酸酯玉米淀粉、磷酸酯木薯淀粉、交联马铃薯淀粉、交联木薯淀粉、醋酸酯玉米淀粉添加量对胸肉的吸水率和失水率的影响。根据单因素实验结果，进行了正交实验，验证得出最优配方为磷酸酯玉米淀粉为0．4％，磷酸酯木薯淀粉为0．8％，交联马铃薯淀粉为0．5％，交联木薯淀粉为0．6％及醋酸酯玉米淀粉为0．06％。经过验证实验所得到的吸水率和失水率的数据分别为7．9％和13．8％。     

处理方法对超高压改性酸解玉米淀粉结晶结构的影响

25℃条件下,质量分数30％的玉米淀粉悬浮液经2．0mol/L盐酸溶液温和酸解24h,得到酸解玉米淀粉。将酸解后的玉米淀粉配制成质量分数5％的淀粉悬浮液,在500MPa压力下处理15min,然后分别立即处理、回生3d（4℃）、冷冻（-20℃）及回生3d后冷冻处理,最后再进行干燥处理。利用X射线衍射仪对样品的结晶度进行测定,结果表明：天然淀粉经过24h的酸解之后相对结晶度有所提高,500MPa高压处理酸解24h的玉米淀粉,能使淀粉颗粒内部的大部分结构发生水合而被破坏,冷冻处理能强化这种破坏作用,但同时又形成了新的B型结晶结构,样品高压后回生3d处理,可以使样品基本上恢复到高压之前的状态。在一定压力范围内,淀粉的高压水合是一个可逆过程。     

国产蜡质玉米淀粉糊性质的研究

主要测定国产蜡质玉米淀粉糊的基本性质。结果为，直链淀粉含量为4．95％，其溶解度略低于相同温度下鲜木薯淀粉的溶解度，与普通玉米淀粉差异不大，膨胀性较好；糊的抗凝沉、冻融稳定性比鲜木薯淀粉好，较普通玉米淀粉优越，品质比国外样品稍差；利用质构仪测定淀粉糊丝的长度，得到蜡质玉米淀粉糊丝长18．8mm；糊的Brabender粘度曲线变化与鲜木薯淀粉相似，粘度比玉米淀粉高，冷糊稳定性较好：蔗糖、食盐、硼砂对糊有增稠的作用；在中等酸性条件下，糊粘度大幅度降低，弱碱性条件下糊粘度略有增加；少量的明矾使糊粘度下降很多；单甘酯对糊粘度性质影响不大。     

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