柱前衍生HPLC法测定鸡脂酶解物中游离脂肪酸含量

建立以2,4-二溴苯乙酮为衍生化试剂,18-冠-6醚为相转移催化剂,同时测定鸡脂酶解物中四种游离脂肪酸的柱前衍生高效液相色谱法.利用Zorbax SB-C18柱(250 mm×4.6mm i.d.,5μm),检测波长254 nm,乙腈和水为流动相进行梯度洗脱,柱温25℃,体积流量1.6 mL/min,外标法定量分析.结果表明:以2,4-二溴苯乙酮为衍生化试剂测定的肉豆蔻酸(15.6～78.1 mg/L)、亚油酸(27.2～136.0 mg/L)、油酸(73.4～367.2 mg/L)和硬脂酸(31.7～158.4 mg/L)在测定范围内呈现良好相关性,相关系数在0.999 3～0.999 8之间.柱前衍生HPLC法简便准确,可用于水解鸡脂中游离脂肪酸含量定量分析.     

高效液相色谱法检测皮革中的甲醛

建立了采用乙酰丙酮-乙酸铵-乙酸试剂衍生后再用HPLC法将多种醛类与衍生试剂反应后的产物用HPLC分离,快速准确检测皮革中甲醛含量的分析方法。考察了乙酰丙酮、乙酸铵试剂,衍生反应条件及衍生产物的稳定性。用乙酰丙酮、乙酸铵试剂柱前衍生,产物经XDB-C18柱(4.6mm×250mm,5μm)柱分离,采用可变波长扫描紫外检测器检测,检测波长412nm;流动相为(乙腈)颐(水)=30颐70(/V),流速为0.8mL/min。方法在0.05～80.0mg/L范围内线性关系良好,相关系数为0.9998,加标回收率为90%～98%,RSD小于5%,检测限为0.01mg/L(S/N=3),可完全满足皮革中甲醛测试的要求。     

高效液相色谱法快速测定紫贻贝中的牛磺酸

目的:建立用高效液相色谱(HPLC)快速测定紫贻贝中牛磺酸含量的方法.方法:应用邻苯二甲醛(OPA)为衍生试剂进行柱前衍生,采用甲醇、乙腈和水(10∶10∶80,v/v/v)为流动相,色谱柱为Agilent Zorbax 300SB-C1s(4.6mm×250mm,5μm),荧光检测:Ex为330nm,Em为530nm,柱温30℃,流速0.8mL/min,进样20μL分析检测牛磺酸含量.结果:牛磺酸在4.0～20.0μg/mL浓度范围内有良好线性关系,相关系数R2为0.9998,回收率范围在96.65％～101.20％,RSD=1.57％.结论:该方法的样品前处理与衍生化简便、易操作,牛磺酸出峰时间为6.752min,其含量为3673.631 mg/kg,有良好的精确度和准确度,分析时间短,可快速检测紫贻贝中的牛磺酸.     

高效液相色谱法测定发芽米胚芽中的γ-氨基丁酸

建立一种高灵敏度的邻苯二甲醛(OPA)柱前衍生荧光检测高效液相色谱法测定发芽米胚芽中γ-氨基丁酸(GA-BA)含量的方法。色谱柱为Shimadzu VP-ODS C18柱(250mm×4.6mm,5μm),流动相:0.05mol/L乙酸钠∶甲醇=60∶40,荧光发射波长λex 338nm,激发波长λem430nm。方法的线性范围为0.10～1.0μg/mL,检出限为0.005μg/mL。日间和日内测定的精密度分别为1.36%和2.54%,加标回收率在98.5%～99.8%。该法简便、快速、灵敏度高,可用于发芽米胚芽中GABA的质量控制。     

HPLC测定注射用盐酸表柔比星的含量

目的 建立HPLC测定注射用盐酸表柔比星的含量.方法 三甲基硅烷键合硅胶柱(250 mm×4.6 mm,5μm),流动相:乙腈-水-甲醇-85％磷酸溶液(290∶540∶170∶1)并含0.2％十二烷基硫酸钠,流速1.0 mL/min,检测波长254 nm,柱温35℃,进样量20 μL.结果 盐酸表柔比星在0.0518～0.1554 mg/ml的浓度范围内有良好的线性关系(r＝0.9999),平均回收率为99.64％(RSD ＝0.71％).结论 此法是一种简便,快速,准确的分析方法,专属性强,能有效地控制盐酸表柔比星的含量.     

钛胶反相高效液相色谱法测定饮料中的柠檬黄

建立了基于钛胶柱对饮料中合成色素柠檬黄的高效液相色谱快速测定方法.色谱条件:分离柱为Titania Sachtopore-RP柱(250 mm×4.6 mm i.d.,5μm),流动相为甲醇:水=45∶55(体积比)、流动相中含乙酸铵1.5 mmol/L,流速0.8 mL/min,柱温35℃,检测波长426 nm.线性范围为5 mg/L～80 mg/L,最低检出限为4μg/L,回收率为91.7％～93.7％,相对标准偏差(n=8)小于0.7％.准确度和精密度均可满足饮料中柠檬黄的测定要求.     

DABS-Cl柱前衍生-HPLC法测定豆豉中的γ-氨基丁酸含量

建立DABS-Cl柱前衍生-HPLC法测定豆豉中的γ-氨基丁酸,样品使用10%三氯乙酸超声提取,经磺酰氯二甲胺偶氮苯(DABS-Cl)衍生,默克RP C18柱(4.6mm×250mm,5μm),流动相A(乙腈∶甲醇为75∶25),流动相B(0.04mmol/L醋酸钠,pH为7.3),检测波长430nm;该方法线性范围为1.50~24.00μg/mL,R=0.9997。重现性相对标准偏差为3.17%,加样回收率为100.83%,该方法样品前处理步骤简单、测定快速、灵敏度高,可用于对该类豆制品物质的测定。     

钛胶反相高效液相色谱法测定饮料中的柠檬酸

建立了钛胶反相高效液相色谱法测定饮料中酸味剂柠檬酸含量的快速检测方法.色谱条件:分离柱为Titania Sachtopore-RP柱(250mm×4.6mm,5μm),流动相为水∶甲醇=60∶40 (v/v)、流动相中含磷酸盐3mmol/L,流速0.SmL/min,柱温60℃,检测波长210nm.线性范围为0.02mg/mL～8.0mg/mL,检出限2.4μg/mL (3σ),回收率为92.79％～99.30％,RSD (n=8) ＜0.72％.准确度和精密度均可满足饮料中柠檬酸的测定要求.     

HPLC法测定市售白酒中的甲醛含量

本研究建立高效液相色谱法测定市售白酒中甲醛含量的分析方法。采用乙腈-2,4-二硝基苯肼和乙酸钠混合体系作为衍生液,在60℃水浴中进行衍生,提取样品中的甲醛。生成的衍生物经色谱柱Inertsil ODS-3-C18(4.6 mm×250 mm,5μm)洗脱,流动相为甲醇∶水(68∶32,V∶V),流速1.0 mL/min,柱温40℃,检测波长为360 nm。结果表明,甲醛在0.0125～1.0 mg/L浓度范围内,线性关系良好,3个不同水平的加标回收率为93.27%～98.06%,RSD值为1.98%,检出限为1.5μg/mL,12种市售白酒中的甲醛含量在0.37～12.98 mg/L之间。该方法操作简单,稳定性好,适用于快速检测白酒中甲醛含量。     

高效液相色谱-柱后光化学衍生-荧光检测法测定强化食品中的叶酸

建立柱后光化学衍生-高效液相色谱法(HPLC)测定强化食品中叶酸的分析方法。方法 采用SunFire C₁₈(4.6 mm×250 mm,5 μm)色谱柱,以乙腈-50 mmol/L磷酸二氢钾溶液(pH=5.0)为流动相梯度洗脱,叶酸在254 nm紫外光照射下进行柱后衍生,荧光检测器检测,激发和发射波长分别为344和428 nm。结果 本方法的线性范围为0.01～2.0 μg/ml,r=0.999 9;方法的定性检出限和定量检出限分别为0.01和0.03 μg/g;加标回收率为90.0%～98.0%,RSD均小于5%。结论 本方法简便、快速、准确、重现性好,适用于强化食品中叶酸含量的测定。     

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.