超高效液相色谱-串联质谱法测定鸡肉、鸡蛋中氟苯尼考和氟苯尼考胺残留

目的建立超高效液相色谱-串联质谱准确测定鸡肉、鸡蛋中氟苯尼考和氟苯尼考胺残留的分析方法。方法鸡肉和鸡蛋样品加入D5-氯霉素内标,经氨化乙酸乙酯混合溶液超声离心提取,提取液减压蒸馏浓缩后,C18固相萃取柱净化处理,采用超高效液相色谱-串联质谱法对氟苯尼考和氟苯尼考胺同时进行检测。结果氟苯尼考线性范围为0.2～20μg/L,检出限为1.0μg/kg,定量限为3.0μg/kg,方法回收率为88.0%～108.0%,相对标准偏差为4.7%～6.4%;氟苯尼考胺线性范围为0.2～20μg/L,检出限为1.0μg/kg,定量限为3.0μg/kg,方法回收率为76.0%～93.1%,相对标准偏差为4.1%～7.2%。结论本方法精确、重现性好,适用于鸡肉、鸡蛋中氟苯尼考和氟苯尼考胺残留量的测定。     

UPLC-MS/MS法测定乳制品中的氯霉素类药物

建立超高效液相色谱-串联质谱(UPLC-MS/MS)法测定乳与乳制品中氯霉素、甲砜霉素和氟苯尼考的检测方法。样品经乙腈及乙酸乙酯提取、正己烷脱脂、C18柱净化后,通过超高效液相色谱-质谱联用仪进行检测,内标法定量。各标准溶液在0.1～10μg/L范围内呈线性相关(r=0.999),不同基质样品中添加回收率为75%～114%,检出限为0.1μg/kg。结果表明,该方法是一种准确测定乳与乳制品中氯霉素、甲砜霉素和氟苯尼考的检测方法。     

增强型除脂固相萃取技术结合超高效液相色谱- 串联质谱法测定动物源性食品中五氯酚残留量

目的建立增强型除脂固相萃取技术结合超高效液相色谱-串联质谱法测定动物源性食品中五氯酚残留量的分析方法。方法样品经8%三乙胺乙腈:水(80:20,V:V)提取,经EMR-Lipid固相萃取柱净化,以5 mmol/L乙酸铵溶液(含0.1%甲酸)-甲醇作为流动相, Waters ACQUITY BEH C_(18)(50 mm×2.1 mm, 1.7μm)进行色谱分离,在电喷雾负离子模式下,多反应监测(multiple reaction monitoring,MRM)方式进行测定,基质匹配外标法定量。结果猪肉、猪肝、鱼、河虾、蟹、牛奶等6种基质中五氯酚在0.5～10 ng/mL范围内线性良好,相关系数r0.997,方法检出限范围为0.1～0.3μg/kg,定量限范围为0.3～0.5μg/kg,在1.0、5.0、10.0μg/kg3个浓度水平下6种基质中回收率范围为81%～98%,相对标准偏差范围为1.74%～4.78%之间(n=6)。结论该方法简单快速、准确可靠,经济环保,重复性好,适用于动物源性食品中五氯酚残留量的测定。     

Captiva EMR-Lipid固相萃取结合高效液相色谱-串联质谱法同时测定猪肉中氯霉素类药物残留量

目的 建立Captiva EMR-Lipid固相萃取结合高效液相色谱-串联质谱法同时测定猪肉中氯霉素、甲砜霉素和氟苯尼考残留量的分析方法。方法 采用乙腈提取样品, 经Captiva EMR-Lipid固相萃取柱净化, 以甲醇-水为流动相, CNW Athena C18-WP色谱柱(100 mm×2.1 mm, 3 μm)进行分离, 采用电喷雾负离子扫描和多反应监测模式, 内标法定量。结果 氯霉素、甲砜霉素和氟苯尼考在0.5~20.0 ng/mL范围内呈现良好的线性关系(r＞0.9975), 方法的检出限为0.10~0.14 ?g/kg, 定量限为0.25~0.47 ?g/kg, 平均回收率为97.50%~117.00%, 相对标准偏差为5.55%~8.93%。结论 该方法简单快速、稳定可靠, 适用于猪肉中氯霉素、甲砜霉素和氟苯尼考的同时测定。     

高效液相色谱-串联质谱法快速测定动物源食品中的氯霉素残留量

目的建立高效液相色谱-串联质谱联用法快速测定动物源食品中氯霉素残留量的分析方法。方法样品采用乙酸乙酯提取、空气吹干浓缩、正己烷脱脂后,经乙腈和水梯度洗脱、色谱柱Poroshell120EC-C_(18)(50 mm×2.1 mm, 2.7μm)分离、液相色谱-串联质谱仪测定,以氘代氯霉素为内标物进行定量。结果回归方程Y=0.177X+0.0008,相关系数r为0.9996;方法检出限和定量限分别为0.03μg/kg、0.1μg/kg;在0.1～1.0μg/kg浓度梯度范围内的平均回收率为91.4%～107.5%,相对标准偏差为4.5%～5.7%,2次能力验证结果满意。结论该方法经济、简便、快捷、稳定、准确性高,能满足大批量动物源性食品样品中氯霉素残留量测定的要求。     

QuEChERS结合高效液相色谱-串联质谱法测定禽蛋中的氯霉素药物残留

目的建立QuEChERS(Quick、Easy、Cheap、Effective、Rugged、Safe)结合高效液相色谱-串联质谱法(HPLC-MS/MS)测定禽蛋(鸡蛋、鸭蛋、鹌鹑蛋、鹅蛋)中的氯霉素药物残留的分析方法。方法 禽蛋样品经乙腈提取,经(PSA∶C18=1∶1)净化处理,采用高效液相色谱-串联质谱法测定,同位素内标法定量。结果 禽蛋基质中氯霉素在0.020～2.0μg/kg线性范围内,相关系数r>0.999;方法检出限0.020μg/kg,定量限0.050μg/kg;在添加浓度水平为0.020、0.10、0.50μg/kg时,回收率范围为80.8%～119.0%,相对标准偏差为4.09%～15.21%(n=6)。采用建立的方法对市购禽蛋样品和天然污染鸡蛋样品进行验证测试,方法实用性满足残留测试要求。结论 本方法前处理操作简便、灵敏度高、可有效用于禽蛋中氯霉素药物残留的监控与定量测定。     

超高效液相色谱串联质谱法测定液态奶中氯霉素、甲砜霉素和氟苯尼考含量

建立超高效液相色谱串联质谱法测定液态奶中氯霉素、甲砜霉素和氟苯尼考的检测方法。样品经乙酸乙酯提取,Oasis MCX小柱净化,用色谱柱WATERS ACQUITY UPLC BEH C18(1.7um, 2.1mm*100mm)分离,同位素内标法定量。在优化条件下,该方法中氯霉素的最低检出限为0.05μg /kg,定量限为0.15μg /kg, 甲砜霉素和氟苯尼考的最低检出限为0.1μg /kg,定量限为0.3μg /kg, 平均回收率为80.4~105.4%,相对标准偏差为2.8~8.4%。该方法灵敏度高、回收率好,具有良好的净化效果,提升检测效率,适用于液态奶中氯霉素、甲砜霉素和氟苯尼考的同时检测。     

高效液相色谱-串联质谱法测定牛奶和奶粉中9种青霉素类药物残留量

建立一种检测牛奶和奶粉中9种青霉素类药物残留量的高效液相色谱-串联质谱方法。样品经乙腈-水提取,经HLB固相萃取柱净化,用高效液相色谱串联质谱检测,外标法定量。本方法的检出限,牛奶中氨苄西林、奈夫西林为1μg/kg,阿莫西林、哌拉西林、青霉素G、青霉素V、氯唑西林为2μg/kg,苯唑西林、双氯西林为4μg/kg;奶粉中氨苄西林、奈夫西林为8μg/kg,阿莫西林、哌拉西林、青霉素G、青霉素V、氯唑西林为16μg/kg,苯唑西林、双氯西林为32μg/kg。9种青霉素在1.0～50ng/mL范围呈良好线性,线性相关系数大于0.9888。牛奶的平均回收率为77.58%～97.77%,测定结果的相对标准偏差为4.24%～16.59%(n=10);奶粉的平均回收率在85.95%～96.78%之间,相对标准偏差为2.71%～13.41%(n=10)。该方法具有简便、快速、准确度高、检出限低的优点,适用于牛奶和奶粉中青霉素类抗生素的测定。     

超高效液相色谱-串联质谱法测定食用猪油中氯酚类物质

目的应用超高效液相色谱-串联质谱技术,建立同时测定食用猪油中2,4,5-三氯苯酚、2,4,5-三氯苯氧乙酸和五氯酚3种物质的方法。方法样品用80%乙腈提取,固相萃取(SPE)和正己烷净化萃取后,以Atlantis?T3(2.1 mm×150 mm,3μm)为分析柱,乙腈-5.0 mmol/L乙酸铵溶液为流动相,以电喷雾离子源在负离子多反应监测模式下进行测定,基质匹配外标法定量。结果 2,4,5-三氯苯酚、2,4,5-三氯苯氧乙酸和五氯酚在2.0～100.0μg/L范围内线性关系良好,相关系数(r)均大于0.999,方法检出限分别为0.09、1.59、0.90μg/kg,定量限分别为0.29、5.28、3.00μg/kg,回收率为71.9%～109.5%,相对标准偏差为0.2%～9.2%(n=6)。结论该方法简便、准确、灵敏度高,适用于食用猪油中2,4,5-三氯苯酚、2,4,5-三氯苯氧乙酸、五氯酚3种物质的高通量检测。     

QuEChERS-UPLC-MS/MS法测定动物源性食品中五氯酚及其钠盐

本文建立QuEChERS-UPLC-MS/MS测定动物源性食品中五氯酚及其钠盐残留量的分析方法。样品用酸化乙腈提取,QuEChERS方法净化。用甲醇和5 mmol/L乙酸铵水溶液作为流动相进行梯度洗脱,C18色谱柱分离。在超高效液相色谱-串联质谱电喷雾电离动态多反应监测负离子模式下定量分析。五氯酚在0.5～15.0 ng/mL线性范围内的相关系数为0.999 96,方法检测限为0.1μg/kg。当不同基质中的标准添加量为1.0～4.0μg/kg时,平均回收率为74.7%～101.4%。本方法操作简单、快速高效,对相关检验检测工作提供参考。     

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.