向老师问路(三十二)

1995年2月,瑞典斯德哥尔摩市出现了免费的都会报--,在地铁等交通要道赠与行人,随后欧洲各国地铁火车等通勤地区开始效仿,陆续出现免费报纸,并且开始流行.2000年,免费报纸的概念传到美洲与亚洲,当时全球有50余种免费报纸,在20多个国家发行,总发行量达800万份.2006年,总发行量增加到3500万份.在欧洲,免费报纸最为流行,冰岛、丹麦、西班牙等国家免费报纸的发行量超过了收费报纸,希腊、匈牙利、意大利、立陶宛、葡萄牙、瑞士、瑞典等国发行量最大的报纸都是免费报纸.根据世界报业协会公布的报告显示,免费报纸已成气候、势不可当,且竞争激烈.丹麦的免费报纸就是最好的例子.     

Analysis and Suggestions for Process Control of Offset Platemaking

International Standard ISO 12218 applies to the process control of offset platemaking for the conventional technology. Based on the comparative analysis the paper shows the necessity of more strict process control for the CtP technology for which there is no common approach among plate manufacturers. Attaining the basic working properties of printing formes and quality parameters of image elements has been suggested as a basis of such an approach.     

"太湖新标"和周边纺企

记者日前从江苏省环保厅了解到,《太湖地区城镇污水处理厂及重点工业行业主要水污染物排放限值》新近出炉,于2008年1月1日起这一标准将在包括无锡、常州、苏州市辖区、南京市溧水县、高淳县,镇江市丹阳市、句容市等太湖流域实施.这是省委、省政府在今年5月太湖蓝藻爆发后,按照铁腕治污、加速调整我省产业结构、淘汰落后产能的要求,组织省环保厅、省质监局编制制定的.     

一些寿山石新品种的宝石学研究

对二号矿石、汶洋石、山仔濑石、房栊岩石、山秀园石、芙蓉石、大山石等一些近年来在寿山石市场上较为常见的寿山石品种进行了研究,详细测定了它们的密度、硬度和矿物组成等.研究表明,二号矿石、房栊岩石和大山石主要由地开石组成,连江黄石、山仔濑石和汶洋石主要含有伊利石,叶蜡石是芙蓉石和山秀园石寿山石品种的主要矿物组成.综合现有的研究资料,建议将寿山石分为田石系、高山石系、月洋石系和连江黄石系.     

创新与环保——纸盒业的双轮驱动力

纸盒业具有巨大的潜力,但生产商如果想要赢得更多的业务,就必须遵循"创新"与"环保"的发展路线. "创新"和"功能"是纸盒和纸盒成形业出现频率较高的词汇,即提供品牌拥有者和零售商所期望并能够花钱购买的产品,同时这个产品还填补了需求的空白.然而也有另外两个词与之威力相当,那就是"可持续(sustainability)"和"再生(recycling)".     

薄利广销加跟踪服务使工业盐销量连年递增——河南新乡市盐业局开创营销创新调研报告

简述了新乡盐业理清思路,更新观念,创新经营,培育市场.薄利广销,跟踪服务,实现供需和谐共赢的经验.为盐行业提供一个典型案例.     

奶香南瓜馅心制作工艺的研究

以南瓜为主要原料,配以花生油、白砂糖、炼乳和精制小麦粉等辅料,制作用于包子、月饼及包馅类点心的奶香南瓜馅心.结果显示,奶香南瓜馅心的最佳配料为在500 g南瓜泥中添加100 g白砂糖、70 g花生油、50 g炼乳和40 g精制小麦粉.该馅心具有南瓜香味和奶香味,色泽鲜亮,口感细腻滑润.     

美国油脂化学家协会在世界贸易中的作用——质量保障检测、有证标准物质和国际联络活动（网络首发、推荐阅读）

The American Oil Chemists’ Society(AOCS) is a volunteer-led association. AOCS develops and publishes methods of analysis for fats, oils, proteins, surfactants, and related materials according to accepted international standards to ensure equitable trade practices on a global scale. AOCS Official Method development has been going on for over a hundred years. The founding vision of AOCS in 1909 was "an organization designed for the development and advancement of analytical methods for cottonseed products." AOCS Official Methods are essential to world trade and are used to confirm the value of billions of pounds of oilseed-based commodities and finished products each year. In addition, AOCS conducts proficiency testing, provides certified reference materials, and collaborates with other standards developers including the International Organization for Standardization(ISO) and the Codex Alimentarius Commission. AOCS serves as a professional scientific membership organization providing current and emerging information as well as disseminating research results in oils, fats, lipids, proteins, surfactants, and related materials. Several avenues are used, especially meetings, publications, interest groups, networking opportunities, and web presence. Many scientists, experts, and others engaged in working in these fields find their professional "home" in AOCS. The AOCS Technical Leadership Committee comprises some of the most experienced AOCS members and scientists. The AOCS Technical Services department staff relies on this committee for guidance on scientific matters and for advice in prioritizing the opportunities facing AOCS.     

宰后肉成熟过程中的风味变化

介绍宰后肉在成熟过程中风味的变化,分别阐述肌糖原、蛋白质、脂类、核苷酸等几类化合物对肉风味的贡献.生肉很少有香味.并且只具有一种类似血腥的味道,但在宰后肉成熟的过程中所产生的丰富的具有味觉属性的化合物.以及香味的前提物质和风味增强剂对肉的感官性质产生巨大影响.     

航展主角——八一飞行表演队J-10AY表演机

正2014年11月,笔者终于如愿以偿参观了第十届中国珠海国际航空航天博览会,轰鸣的军用喷气式发动机给笔者带来了极大的震撼,而作为主场表演的中国空军八一飞行表演队以及装备的J-10AY表演机则可以称得上是当之无愧的主角。不仅仅是飞行表演带来的震撼,在地面做静态展示的01号表演机更让笔者这样的老军迷第一次有机会近距离接触这种从学生时代就让笔者魂牵梦绕的主力装备。在大饱眼福并且用各个角度的细节照片装满了相机的     

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.     

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.     

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.     

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.     

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.     

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.     

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.