酶法制取葡萄糖的工艺技术

采用酶法水解与目前先进的过滤、离子交换及蒸发浓缩等下游工程技术结合，研究葡萄糖加工的工艺条件与提高产品纯度和得率的实用技术。通过实验确定最佳工艺条件为：液化时，pH6.0-6.5，温度85℃，时间40min，α-淀粉酶用量0.3％，淀粉浆浓度30％；糖化时，pH4.2～4．5，温度60℃，时间48h，糖化酶用量0.6％。     

壳聚糖对桑果汁澄清效果的研究

处理后的桑椹汁在720mn处有最大吸收波长。用壳聚糖对桑棋汁进行澄清实验结果表明，壳聚糖用量为0．4-0．7g／L、pH2．5～4．5、温度35～55℃时的工艺条件处理桑椹果汁时，果汁的透光率能达剑80％以上，果汁中的可溶性同形物及Vc含量基本不变。正交实验显示，壳聚糖对桑椹汁的最适工艺条件是：壳聚糖用量为0．6g／L，温度为45℃，果汁pH为4．5。     

含酒精型玉米发泡饮料的工艺研究

对以玉米为主要原料，以啤酒酵母为菌种，发酵酿制低酒精度的发泡饮料进行了研究。通过试验确定了蒸煮最佳工艺条件，时间为50min，打浆加水比为1：4，菌种的用量为10％；液化温度70℃、25min、pH5．5、α-淀粉酶用量0．25％：糖化温度61℃、1h、pH4．5、糖化酶用量0．5％：发酵温度15℃、48h、pH6．5、啤油酵母用量10％。酿制的产品具有千米特有的香味和营养价值。     

交联酯化蜡质玉米淀粉的制备

以特征黏度峰值、交联度（溶胀法）及取代度为评价指标,研究了对热、酸和剪切力的影响具有高稳定性的交联酯化蜡质玉米变性淀粉的制备过程。得出制备条件为：环氧氯丙烷用量0．49／6,交联pH值10．85,交联温度40℃,交联时间4h,醋酸酐用量6％,酯化温度20℃～25℃,酯化pH值8．0～8．5,酯化时间30min。     

鲢鱼中肌原纤维蛋白酶法水解的研究

通过测定水解度及对水解液进行感官评价,研究了鲢鱼肌原纤维蛋白的酶水解条件与脱苦脱腥味条件。结果表明：胰蛋白酶单酶水解的最佳条件为：酶用量1．5％,pH8．0,温度45℃,水解时间5h;木瓜蛋白酶单酶水解的最佳条件为：酶用量1．0％,pH7．0,温度50℃,水解时间6h。双酶水解的最佳组合为先加木瓜蛋白酶水解3h,后加胰蛋白酶水解2h。在水解液中添加2．0％～2．5％活性炭,于40℃保温0．5h的脱苦脱腥效果较佳。     

微生物蛋白酶对大豆分离蛋白水解作用的研究

研究了五种蛋白酶对大豆分离蛋白的水解效果,筛选出效果最好的碱性蛋白酶Alcalase（液态）。并研究了pH值、温度、酶浓度、底物浓度、水解时间对该酶水解效果的影响。结果表明：最佳工艺条件为：温度55℃、pH值8．0、底物浓度2％、酶用量5％（E:S）、水解时间为4～6h。     

麦草木质素磺酸钠制备缓释氮肥的研究

通过对尿素改性后木质素磺酸钠产品中总氮和铵态氮含量的分析测定,研究了改性反应pH值、反应时间、温度、尿素用量等工艺条件对尿素改性麦草木质素磺酸钠制备缓释有机氮肥的影响。结果表明：pH4、温度70℃、时间4h、尿素／木质素（w／w）为1．6时,是较为理想的反应条件,改性木质素磺酸钠产品的总氮含量为5．85％,铵态氮含量为0．48％。     

芦苇硫酸盐氧脱木素浆二氧化氯漂白研究

研究了芦苇硫酸盐氧脱木素浆的D0EpD1漂白,重点优化了漂白工艺参数,并对高温二氧化氯漂白进行了探讨。研究结果表明,芦苇硫酸盐氧脱木素浆用D0EpD1流程进行漂白,D0段漂白的最优工艺条件为漂终pH值3．0—4．0,ClO2用量O8％-1．0％,保温时间60min,温度60℃,漂终pH值对D。段漂白结果的影响较大;D0段ClO2用量所占的比例在5／8—6／8之间得到的漂白浆白度最高;在优化的漂白工艺条件下,当第一段ClO2采用85℃高温漂白时,漂终白度可达83．2％ISO;当第一段ClO2采用常规温度漂白时,漂终白度可达82．0％ISO。     

巴西菇多糖提取方法研究

本文探讨了巴西菇多糖的提取工艺，分别作了热水提取和酶法提取的正交试验，并对多糖提取率进行了比较分析。结果显示．热水提取巴西菇多糖的最佳工艺参数是：提取温度110℃，提取时间1．5h，料液比1：25，其多糖最高提取率5．80％。而采用酶法提取巴西菇多糖的最佳工艺参数分别是：木瓜蛋白酶酶用量0．20％，酶解温度55℃，酶解时间2h，作用pH值6．5；纤维素酶酶用量O．15％，酶解温度45℃，酶解时间3h，作用pH值4．5；果胶酶酶用量O．20％，酶解温度40℃，酶解时间3h，作用pH值4．0。其中木瓜蛋白酶提取巴西菇多糖提取率最高，可达到15．08％。     

磷酸酯化对甘薯淀粉凝沉性质的影响

对甘薯淀粉的磷酸酯化制备条件及产物的凝沉性质进行了系统研究，结果表明，甘薯淀粉磷酸单酯的最适制备工艺为：NaH2PO4：Na2HPO4=3：l；反应温度130℃～140℃：反应时间2～3h，pH5．5～6．0，催化剂用量为淀粉千基重的4％～6％。甘薯淀粉经过磷酸酯化反应后可能在脱水葡萄糖单元上引入了磷酸基团，从而导致了淀粉凝沉性质的变化，使得淀粉糊的凝沉趋势降低，透明度增高，冻融稳定性提高。     

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