不同萃取头固相微萃取分析小米清酒挥发性成分的研究

采用PA、PDMS、PDMS/DVB、CAR/PDMS和DVB/CAR/PDMS 5种萃取头,并通过固相微萃取（SPME）与气质联用（GC-MS）对小米清酒中挥发性成分进行提取、鉴定,运用聚类热图分析不同SPME萃取头提取小米清酒挥发性成分差异。结果表明：5种萃取头SPME检测到小米清酒挥发性成分含有醇、酯、醛、碳氢化合物、含苯衍生物和其他化合物,使用不同萃取头进行固相微萃取能得到较为相似的主挥发性成分：1-戊醇、苯乙醇、正己酸乙酯、丁二酸二乙酯、辛酸乙酯、十六烷,DVB/CAR/PDMS萃取头检测效果最好。聚类热图显示,不同萃取头SPME提取到的挥发性成分效果差异较大,按萃取效果可分为PA萃取头、PDMS萃取头和复合萃取头（PDMS/DVB、CAR/PDMS和DVB/CAR/PDMS）三类,使用不同种萃取头SPME可较为全面地了解小米清酒挥发性成分构成。     

固相微萃取-气-质联用法测定大菱鲆鱼肉挥发性成分条件的优化

采用顶空固相微萃取-气相色谱-质谱联用法分析大菱鲆鱼肉中的挥发性成分,对影响萃取效率的关键因素进行优化,分析各因素对不同相对分子质量化合物萃取效果的影响。结果表明:在3 g鱼肉中加入6 mL饱和氯化钠溶液(0.36 g/mL),用50/30μm DVB/CAR/PDMS的萃取头于50℃下萃取40 min,能够达到较好的萃取效率。在最佳萃取条件下提取大菱鲆鱼肉的挥发性成分,结合GC-MS共鉴定出38种主要挥发性物质,包括醛类、醇类、烃类、酮类和胺类化合物,其中醛类和醇类化合物的相对含量较高,分别为36.98%和33.15%,为新鲜大菱鲆鱼肉的主要挥发性成分。     

萃取头对甜面酱中挥发性成分分析的影响

采用顶空固相微萃取(HS-SPME)与气质联用(GC-MS)相结合对甜面酱中挥发性成分进行了初步分析,比较了4种不同涂层纤维的萃取头(30μm PDMS,65μm PDMS/DVB,75μm CAR/PDMS,50/30μm DVB/CAR/PDMS)对甜面酱挥发性成分的萃取效果和特点。结果表明:在相同实验条件下,50/30μm DVB/CAR/PDMS萃取头萃取到的色谱总峰面积和化合物种类最多,而75μm CAR/PDMS萃取头可以萃取到最多的香气成分。因此50/30μm DVB/CAR/PDMS萃取头最适合甜面酱挥发性成分的检测,同时可以用75μm CAR/PDMS萃取头来进行补充。     

采用3种萃取纤维头的顶空固相微萃取法萃取荜茇果穗挥发性成分

采用顶空固相微萃取法萃取荜茇果穗挥发性成分,并用GC-MS进行分析.3种萃取纤维头共萃取出49个成分,鉴定出42个成分.使用DVB/CAR/PDMS萃取纤维头时共检测出36种成分,解析鉴定出占总成分99.834%的35种成分,主要成分为β-石竹烯(17.933%)、β-毕澄茄油烯(15.892%)、十五烷(8.285%...     

红枣白兰地香气成分萃取中固相微萃取纤维的选择

目的:针对红枣白兰地香气成分气相色谱分析的要求,比较3种固相微萃取纤维萃取红枣白兰地香气成分的效果。方法:选取常用的CAR/DVB/PDMS、PDMS/DVB、PDMS 3种固相微萃取纤维进行红枣白兰地香气成分的富集和浓缩处理,然后用气-质联用法检测香气成分。通过对不同固相微萃取纤维萃取香气成分的数量、化学种类以及各类化合物累积峰面积标准化值的比较,评价供试固相微萃取纤维萃取红枣白兰地香气成分的效果。结果:红枣白兰地香气成分中,酯类、醛酮类、醇类、萜烯类是主要成分,酸类和烷烃类等是微量成分。不同固相微萃取纤维萃取的化合物存在明显差异,用DVB/CAR/PDMS萃取化合物118种,总含量较多;用PDMS萃取出119种,总含量较少;用PDMS/DVB仅萃取出88种,总含量最多。累积峰面积标准化值分析表明,DVB/CAR/PDMS萃取2类酯、醇类、萜烯类和醛酮类的效果最好,萃取其他成分效果居中;PDMS萃取酸类效果最好,而萃取甲乙酯、醇类、萜烯类和醛酮类效果最差;PDMS/DVB萃取乙酯类化合物的效果最好,萃取其他酯、酸类的效果最差。结论:在供试的3种固相微萃取纤维中,DVB/CAR/PDMS是萃取富集绝大多数红枣白兰地挥发性成分的最佳纤维。     

固相微萃取-气相色谱-质谱法分析带鱼肉的挥发性成分

采用固相微萃取-气相色谱-质谱联用技术分析带鱼肉的挥发性成分,以鱼肉中8种主要挥发性物质为参照对象,对影响萃取效率的关键因素进行了优化。结果表明:在2g鱼肉中加入6mL饱和氯化钠溶液(0.36g/mL),用50/30μm DVB/CAR/PDMS的萃取头于50℃下萃取50min能够达到较好的萃取效果;在此条件下提取带鱼肉的挥发性成分,共鉴定出40种化合物,其中醛类、醇类、芳香族和烯烃类化合物的相对含量较高,分别为45.11%、17.47%、14.49%和13.99%,为带鱼肉的主要挥发性成分。     

顶空固相微萃取-气质分析白芷香气成分研究

采用顶空固相微萃取和气相色谱-质谱研究白芷的香气成分。萃取纤维头为CAR/PDMS时共检测出35个成分,解析出占总挥发性成分的93.897%(相对百分含量,以下同)的33种物质,主要成分是1,8-桉树脑(16.713%),柠檬烯(15.495%),对伞花烃(7.620%)。萃取纤维头为DVB/CAR/PDMS时共检测出53种挥发性成分,解析出占总挥发性成分的91.360%的45种物质,主要成分是桉树脑(12.529%),依次为茴香脑10.836%,β-石竹烯8.922%。     

固相微萃取（SPME）在天然乳脂风味物质分析中的应用研究

采用固相微萃取吸附富集天然乳脂的挥发性成分,然后用气相色谱-质谱联用分析鉴定,并对3个固相微萃取头进行了比较。天然乳脂的挥发性成分主要是一些酮醛类,酸类和内酯类物质,但不同固相微萃取头对天然乳脂的各挥发性成分的吸附性能有所差别。本试验对CAR／PDMS、PDMS／DVB、PDMS三种固相微萃取头进行了选择,结合GC-MS分析发现PDMS／DVB对天然乳脂挥发性风味物质的吸附效果最好,能检出21种挥发性物质,其中酮醛类7种,酸类9种,内酯类4种。SPME-GC／MS为乳脂风味物质的研究提供了新的参考方法。     

固相微萃取（SPME）在天然乳脂风味物质分析中的应用研究

采用固相微萃取吸附富集天然乳脂的挥发性成分,然后用气相色谱-质谱联用分析鉴定,并对3个固相微萃取头进行了比较。天然乳脂的挥发性成分主要是一些酮醛类,酸类和内酯类物质,但不同固相微萃取头对天然乳脂的各挥发性成分的吸附性能有所差别。本试验对CAR／PDMS、PDMS／DVB、PDMS三种固相微萃取头进行了选择,结合GC-MS分析发现PDMS／DVB对天然乳脂挥发性风味物质的吸附效果最好,能检出21种挥发性物质,其中酮醛类7种,酸类9种,内酯类4种。SPME-GC／MS为乳脂风味物质的研究提供了新的参考方法。     

顶空固相微萃取结合气质联用分析沙葱中挥发性成分

沙葱是一种生长于荒漠地带的野生蔬菜,具有独特的气味。为了确定其挥发性成分,实验采用顶空固相微萃取技术(HS-SPME)对其挥发性成分进行萃取,然后用气相色谱质谱联用(GC-MS)进行检测。结果表明,共检测到24种化合物,在DVB/CAR/PDMS、PDMS/DVB、PA三种固相萃取头中,DVB/CAR/PDMS型号的萃取头萃取效果最佳;沙葱中主要挥发性成分是:2-己烯醛(27.74%)、甲基-2-烯丙基三硫醚(25.70%)、二甲基三硫化物(13.62%)、烯丙基甲基二硫醚(9.94%)、二烯丙基二硫(7.23%),占总成分的84.23%,其中2-己烯醛在沙葱中首次报道。     

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.     

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.     

Review of techniques to manufacture micro-hydrogel particles for the food industry and their applications

Microgels are ‘soft’ microscopic cross-linked polymeric particles that are being increasingly exploited in a variety of industries for rheology control, encapsulation and targeted delivery. They are valued because of the ability to tune their functionality to address specific applications in oil recovery, coatings, drug delivery, cosmetics, personal care and foods. Food microgels are typically biopolymer hydrogels in the form of microspheres, nanospheres (also called nanogels), spheroids and fibres. The utilisation of engineered microgels in foods has so far been limited, despite their great potential to address several needs in the food industry, including: satiety control, encapsulation of phytonutrients and prebiotics, texture control for healthier food formulations (e.g. reduced fat products), and targeting delivery to specific areas in the digestive tract. We review the scientific and patent literature on the utilisation and manufacturing methods for producing microgels with an emphasis on micro-hydrogels for food applications.     

12—A CRITIQUE OF SOME HYPOTHESES RELATING TO THE HETEROGENEITY OF THE HIGH-SULPHUR PROTEINS OF WOOL

Joubert and Burns prepared a large number of fractions from the high-sulphur proteins of wool and estimated their molecular weights and amino-acid compositions. Their data have been re-examined in order to look for statistically significant interrelations between amino acids and between the proportion of various amino acids and molecular weight. Statistical analysis of the data is also used to examine the credibility of some hypotheses concerning the mechanism of keratin biosynthesis and to provide further evidence for the existence of families of proteins within the high-sulphur fractions of wool.     

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.     

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 Latest Data about Development of Chinese Printing Industry in 2013

In the 2014 China（Shanghai）International Printing Week,Director Wang Yanbin released the latest data about development of Chinese printing industry in 2013.According to statistics,in 2013,the total output value of Chinese printing industry exceeded 1trillion Yuan for the first time,reaching 1.03985 trillion Yuan.There were 105,000 printing enterprises in China,employees were 3.415 million.The total asset was 1.06247 trillion Yuan;     

The State Council Issued "Directory of Government Approved Investment Projects(2013 Edition)"

正On December 2nd,2013,the State Council issued the notification of"Directory of Government Approved Investment Projects(2013 Edition)"(hereafter referred to as"notification").It is pointed out in the"notification"that in order to further deepen reforms in investment systems and administrative examination and approval systems,simplify administrative procedures and delegate powers to lower levels,earnestly     

China textile machinery: taking off in progress

正Among the 1600 exhibitors who take apart in the ITMA ASIA+CITME2014 2/3 are Chinese manufactures.If the numerous figures failed to attract your attention,the increase of quality should draw your focus.To adopt the demand of developing textile machine market,domestic textile machinery enterprises now follow the slogan of"technology drives development"to enhance product competitiveness.Our domestic sellers will showcase product ranging from spinning,weaving,dyeing and printing,     

Top Ten News of China's Paper Industry 2013

On December 24th, 2013, the meeting on the selection of top 10 news of China＇s paper industry 2013 sponsored by 〈China Paper Newsletters〉 was held in Beijing. The yearly selection of the top l0 news, which began in 2000, has become a brand activity widely recognized in the industry thanks to the support from the authorities at all levels and public participation.