我国粮食期货市场与现货市场价格传导关系的研究

为研究我国粮食期货市场价格发现功能发挥的程度以及对现货市场的影响,采用Johansen协整检验、Granger因果检验、脉冲响应函数、方差分解等方法,以大豆、玉米、小麦为对象,对我国粮食期货市场与现货市场价格的传导关系进行了实证分析。结果表明,我国粮食期货价格与现货价格间存在长期均衡关系,它们之间表现出以期货价格向现货价格传导为主的单向传导关系,现货价格向期货价格的传递受到一定程度的阻滞。其中,大豆和小麦期货市场与现货市场的价格传导速率为1阶滞后,玉米为3阶滞后;我国粮食期货价格向现货价格传导的内在动力主要在于期货市场的价格发现功能得以充分实现,期货价格信息标准规范,并能够借用现代网络技术有效畅通地传递到现货市场中;而粮食现货市场因交易方式落后、信息化水平低下、市场信息标准不规范等因素,制约了现货市场信息向期货市场的传递。     

基于MSVAR模型的市场情绪、豆粕期货现货价格的相关性研究

选取2015年5月到2018年5月的数据,从非线性的角度实证检验市场情绪、豆粕期货价格和现货价格间的均值溢出关系。结果表明:豆粕期货价格与市场情绪之间相互产生正向响应;市场情绪对豆粕现货价格的响应为负向,豆粕现货价格会对市场情绪的变动产生正向响应;豆粕期货价格和现货价格具有双向均值溢出关系,这表明豆粕期货价格具有价格发现功能;市场情绪是豆粕期货价格和现货价格发生关系的中间因素。     

股指期货与股指现货的协整与因果关系研究

运用协整理论对我国刚刚上市的股指期货与股指现货进行研究,探索两者之间的内在关系.结果表明,股指期货与股指现货存在协整关系;通过Granger因果检验发现,股指期货与股指现货存在单边因果关系;通过协整模型和修正误差模型确证了股指期货与股指现货的长期均衡和短期波动关系.     

市场情绪、豆油期货价格和现货价格的相关性研究——基于MSVAR模型的实证检验

从非线性的角度实证检验了市场情绪、豆油期货价格和豆油现货价格之间的相关关系。结果表明:豆油期货价格与市场情绪相互产生正向响应;市场情绪对现货价格产生正向效应,现货价格对市场情绪产生负向效应;豆油现货和期货价格间存在均值溢出效应。最后提出了相关建议。     

国际棉花套期保值案例

在纽约棉花期货交易所推出棉花期货以前,国际现货市场棉花价格波动很大,供求关系的突然失衡会造成价格的剧烈波动并严重冲击棉花的生产和贸易。为了克服现货市场固有的风险,1870年纽约棉花交易所应运而生,并于当年推出棉花期货交易。随着棉花期货市场的不断发展,尤其是20世纪70年代以后,棉花期货价格越来越受到重视,其规避风险和发现价格的功能充分发挥出来,最近交割月期货价格与孟菲斯地区的现货价格走势非常一致。现在纽约棉花期货价格已成为美国政府制定有关棉花政策的主要参考依据,也是除中国外其他主要产棉国棉农和涉棉企业套期保值的…     

临储政策主导下我国油菜籽市场展望

<正>在今年全球油脂油料市场供给增加大背景下,油脂价格下行压力加大、致使我国临储菜籽油拍卖屡屡流拍。基于对油菜籽市场政策市基本判断,并受油菜籽收储价格稳中有升支撑,今年油菜籽价格在政策执行期内将获得支撑。鉴于全球油脂油料市场运行态势疲软,及国内菜籽油高库存、高成本现状,若油菜籽托     

市场情绪、棉花期货价格和现货价格的相关性研究-基于MSVAR模型的实证检验

选取2015年5月至2018年4月的相关数据,从非线性的角度实证检验了市场情绪、棉花期货价格和棉花现货价格之间的相关关系。分析结果表明:棉花市场存在低迷、平稳及高涨3种状态;在3种状态下,棉花期货价格与市场情绪相互产生正向效应,市场情绪对现货价格产生正向效应;现货价格在市场低迷和高涨状态下对市场情绪产生负向效应;棉花现货和期货价格间存在均值溢出效应。根据分析结果,最后对稳定棉花市场提出了相关建议。     

不同区域禽蛋价格传导分析

利用Johansen协整检验等数学方法对我国禽蛋主产和主销区28对市场组合的价格传导情况进行了分析。结果表明,我国禽蛋主产区和主销区价格存在协整关系,并且禽蛋价格传导路径以从销区向产区传递和相互影响为主,表明我国禽蛋市场是消费主导型。     

期货交割棉的加工工艺流程和质量控制

自2004年6月1日我国棉花期货在郑州商品交易所推出以来，受到了业界的广泛关注。由于影响棉花现货市场和期货市场的因素存在差异，期货价格有时会明显高于或低于现货价格，从而形成期现跨市套利的机会。而标准仓单的制做和流通，正是棉花企业进行跨市套利，以规避现货市场变化风险、锁定经营利润的必经环节。     

中国粮油市场2012年6月份分析报告

<正>6月份,我国夏收全面结束,新作小麦质量问题,给"九连增"带来阴霾。由于质量和资金原因,大多地区小麦价格低于最低收购价格水平,安徽、江苏、湖北、河南、山东相继启动小麦最低收购价"预案"。另一夏收作物油菜籽临储收购任务也正式下达到企业,在6月下旬迎来油菜籽收购、上市高峰期。6月份,欧债危机走势主导国际市场油脂油料价格,并传递至我国市场。在输入性上涨推动下,国内植物油价格止跌,并持续反弹回升;不过由于我国植     

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.     

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.     

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.     

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.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.