超高效液相色谱-串联质谱法测定白酒中9种甜味剂

目的建立准确、快速检测白酒中安赛蜜、糖精钠、甜蜜素、阿斯巴甜、三氯蔗糖、纽甜、阿力甜、甜菊糖苷和甜菊双糖苷9种甜味剂的超高效液相色谱-串联质谱分析方法。方法样品经沸水浴加热除去乙醇,采用超高效液相色谱-串联质谱法进行检测。以水(含10 mmol/L乙酸铵)和甲醇为流动相, HSS T3色谱柱(2.1 mm×100 mm,1.7μm)进行分离,电喷雾离子化多反应监测模式检测。结果 9种甜味剂在相应线性范围内关系良好,相关系数均≥0.999;方法回收率为85.2%～102.8%,相对标准偏差(RSD)为3.8%～7.3%;检出限为0.3～1.5μg/kg。结论该方法操作简单快速、重现性好,可用于白酒中9种甜味剂的检测。     

超高效液相色谱-串联四级杆质谱法测定白酒中甜蜜素和糖精钠的含量

目的建立超高效液相色谱-串联四级杆质谱法测定白酒中甜蜜素和糖精钠的含量。方法将白酒样品用超纯水直接稀释50倍,经0.22μm滤膜过滤后上机进行分析,采用Hypersil GOLD?C18色谱柱分离,以5 mmol乙酸铵和甲醇为流动相梯度洗脱,流速为0.2 mL/min,柱温为35℃,外标法定量。结果甜蜜素和糖精钠在10～500μg/L范围内具有良好线性关系。样品中添加不同浓度的甜味剂时,甜蜜素的平均回收率为91.1%～98.3%,相对标准偏差为1.9%～4.1%;糖精钠的平均回收率在90.2%～97.6%,相对标准偏差为2.1%～4.3%。结论该方法适用于白酒中甜蜜素和糖精钠含量的测定。     

超高效液相色谱-电喷雾串联质谱测定食品中对位红的检测方法研究

建立了超高效液相色谱-电喷雾串联质谱法测定食品中对位红的检测方法。样品经提取后,采用了Waters Oasis HLB作为固相萃取小柱,进行样品净化,经超高效液相色谱分离后采用电喷雾串联质谱进行定性及定量检测。线性范围为0.1～1.0mg/L,线性相关系数为0.999。方法的定性检出限(S/N=3)为0.26μg/kg,定量检出限(S/N=10)为0.85μg/kg。高、中、低3个浓度水平的加标回收率范围为80.5%～109.5%,相对标准偏差小于10%。     

超高效液相色谱-串联质谱法直接测定白酒中8种甜味剂

建立了超高效液相色谱-串联质谱仪(UPLC-MS/MS)测定白酒中8种甜味剂(安赛蜜、糖精钠、甜蜜素、阿斯巴甜、三氯蔗糖、纽甜、阿力甜和甜菊糖苷)含量的分析方法。样品经蒸馏水稀释一定倍数后,过0.22μm微孔滤膜,直接进入UPLC-MS/MS中分析检测。Waters HSS T3色谱柱为分析柱,甲醇-0.1%乙酸水溶液为流动相进行梯度洗脱,在电喷雾电离源负离子模式下,采用多反应监测模式进行检测。结果表明,8种甜味剂在10~500μg/L的范围内线性关系良好(相关系数r0.996),方法检出限在1~3μg/L之间,基质加标回收率在89%~106%之间,相对标准偏差≤9%,均可达到白酒中痕量甜味剂的检测要求。该方法前处理简单,测定快速、准确、灵敏度高,非常适合白酒中多种甜味剂的快速筛查和定量分析。     

超高效液相色谱-串联质谱法同时测定白酒中氨基甲酸乙酯和8种甜味剂

建立了超高效液相色谱-串联质谱仪(ultra performance liguid chromatograph-tandem mass spectrometry,UPLC-MS/MS)同时测定白酒中氨基甲酸乙酯和8种甜味剂(安赛蜜、糖精钠、甜蜜素、阿斯巴甜、三氯蔗糖、纽甜、阿力甜和甜菊糖苷)含量的新方法。样品经超纯水稀释2倍,微孔滤膜过滤后直接进样,用液相色谱-串联质谱(liguid chromatograph-tandem mass spectrometry,LC-MS/MS)进行定量分析。Waters HSS T3色谱柱为分析柱,甲醇-0.1%乙酸水溶液为流动相进行梯度洗脱,采用电喷雾电离源正负离子切换多反应监测模式检测。结果表明:氨基甲酸乙酯和8种甜味剂在3~500μg/L的范围内线性关系良好(相关系数r0.998),方法检出限在1~3μg/L,基质加标回收率在89%~106%,相对标准偏差≤9%,完全满足日常检测的要求。该方法前处理简单,测定快速、准确、灵敏度高,非常适合白酒中氨基甲酸乙酯和多种甜味剂的快速筛查和定量分析。     

超高效液相色谱-串联质谱同时检测白酒中7种甜味剂

建立了一种同时检测白酒中最常见的7种人工合成甜味剂(安赛蜜、糖精钠、甜蜜素、纽甜、三氯蔗糖、阿斯巴甜、甜菊糖苷)的超高效液相色谱-串联质谱(UPLC-TQS)检测方法。白酒样品于120℃电热板加热去酒精处理后,用超纯水定容,过0.22μm滤膜后进行UPLC-TQS分析。样品以甲醇和0.1%甲酸水作为流动相梯度洗脱,经ACQUITY UPLC HSS T3(100 mm×2.1 mm, 1.8μm)色谱柱,流速为0.35 mL/min,柱温为40℃,采用电喷雾电离源负离子模式检测,进样时间为6.5 min。经检测,7种甜味剂在各自的线性范围内均有较好的线性关系,线性相关系数R2均大于0.999。检出限在0.1～6 ng/mL。加标回收率为91.8%～114%。该方法简单、快速,结果准确,灵敏度高,可直接用于白酒中7种甜味剂的日常监督检测。     

高效液相色谱法测定白酒中甜蜜素

采用高效液相色谱法测定白酒中甜蜜素含量.检测条件:色谱柱ODSHypersil,流动相:甲醇:水=80∶20,流速1.0 mL/min,检测波长314 nm.结果表明,线性范围10～200 μg/mL,回收率93.15%～106.67%,相对标准偏差1.2%～2.8%,定性检测下限1.0 μg/mL,定量检测下限2.0μg/mL.该法简便,适合白酒中甜蜜素含量的测定.     

UPLC/MS/MS法测定饮料中甜蜜素、糖精钠和安赛蜜

建立了超高效液相色谱-串联质谱法(ultra high-performance liquid chromatography-tandem massspectrometry,UHPLC-MS/MS)测定饮料中甜蜜素、糖精钠和安赛蜜的检测方法。饮料加水稀释涡旋,用N-丙基乙二胺(PSA)净化样品,经0.22μm微孔滤膜过滤后测定甜蜜素;用乙酸锌-亚铁氰化钾净化样品,经0.22μm微孔滤膜过滤后测定糖精钠和安赛蜜。甜蜜素和安赛蜜在5～200μg/L、糖精在20～200μg/L范围内线性关系良好,方法检出限(S/N=3)为0.2～10μg/kg,方法定量限(S/N=10)为0.6～30μg/kg,3种化合物在奶茶中加标回收率为78.9%～95.7%,果茶中加标回收率为80%～102%。方法操作简单,检出限低,重现性好,回收率良好,干扰小。     

麻辣熟食中甜蜜素的GC检测和质谱确证

建立了气相色谱分析及液相色谱-串联质谱确证方法对麻辣熟食中甜蜜素的检测方法,比较了气相色谱法(GC)与液相色谱-串联质谱法(LC-MS/MS)检测方法的适用性。提取方法采用超声波提取,经石油醚萃取除油除脂,沉淀剂去蛋白质和脂肪,由气相色谱法初筛、高效液相色谱-串联质谱法做阳性样品确证检测麻辣熟食中甜蜜素的方法。GC法中甜蜜素含量在0.010 0~0.300 0 mg/mL的范围内与峰面积有良好的线性关系,相关系数为0.999 55,检出限为0.005 2 g/kg。甜蜜素添加浓度在0.020 0,0.040 0和0.200 g/kg时,添加回收率分别在90.0%~98.0%之间,测定结果的相对标准偏差为3.1%~5.2%(n=6);液质联用作为甜蜜素的确证方法,检测低限为2.2μg/kg。结果表明:建立的甜蜜素检测和确证方法简便、经济、快速、准确,适用于麻辣熟食中甜蜜素测定。     

UPLC-MS/MS法分析茶叶中的灭多威农药残留

建立了检测茶叶中灭多威残留的超高效液相色谱-串联质谱(UPLC-MS-MS)分析方法。茶叶样品经乙腈提取,氨基固相萃取柱净化,反相液相色谱对样品进行分离,采用多反应监测模式(MRM)进行定性、定量分析。结果表明:方法检出限为0.5μg/kg,定量限为2.0μg/kg;当添加浓度水平为10、100μg/kg时,加标回收率为71.9%～113.5%,相对标准偏差为5.3%～12.5%。该法灵敏度高、干扰小、定性准确,适用于茶叶中灭多威残留检测,同时可作为液相色谱检测的验证方法。     

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.     

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.     

Analysis for organic residues from aids to polymerization used to make plastics intended for food contact

Polymers intended for food contact use have been analysed for organic residues which could be attributed to a range of substances employed as polymerization aids (e.g. initiators and catalysts). A wide range of polymers was extracted with solvents and the extracts analysed by gas chromatography-mass spectrometry (GC-MS). The overwhelming majority of substances identified were not derived from aids to polymerization but were oligomers, additives and adventitious contaminants. However, a small number of substances were identified as initiator residues. These included tetramethylsuccinonitrile (TMSN) which was observed in two polymers and it derived from recombination of two azobisisobutyronitrile (AIBN) initiator radicals. Methyl benzoate, benzoic acid, biphenyl and phenyl benzoate were detected in one poly(methyl methacrylate) sample and in two polyvinylchlorides and they are thought to be derived from benzoyl peroxide initiator. TMSN was subsequently targeted for analysis of poly-(methyl methacrylate) plastics using proton nuclear magnetic resonance spectrometry (¹     

Tests of potential functional barriers for laminated multilayer food packages. Part II: Medium molecular weight permeants

Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. I: Interlaboratory studies of methods of analysis

This paper describes the first part of a project undertaken to develop mussel reference materials for Paralytic Shellfish Poisoning (PSP) toxins. Two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin (STX) and decarbamoyl-saxitoxin (dc-STX) in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the second part of the project: the certification exercise. In the first study, 18 laboratories were asked to measure STX and dc-STX in rehydrated lyophilized mussel material and to identify as many other PSP toxins as possible with a method of their choice. In the second interlaboratory study, 15 laboratories were additionally asked to determine quantitatively STX and dc-STX in rehydrated lyophilized mussel and in a saxitoxin-enriched mussel material. The first study revealed that three out of four postcolumn derivatization methods and one pre-column derivatization method sufficed in principle to determine STX and dc-STX. Most participants (13 of 18) obtained acceptable calibration curves and recoveries. Saxitoxin was hardly detected in the rehydrated lyophilized mussels and results obtained for dc-STX yielded a CV of 58% at a mass fraction of 1.86 mg/kg. Most participants (14 out of 18) identified gonyautoxin-5 (GTX-5) in a hydrolysed extract provided. The first study led to provisional criteria for linearity, recovery and separation. The second study revealed that 6 out of 15 laboratories were able to meet these criteria. Results obtained for dc-STX yielded a CV of 19% at a mass fraction of 3.49mg/kg. Results obtained for STX in the saxitoxin-enriched material yielded a CV of 19% at a mass fraction of 0.34mg/kg. Saxitoxin could not be detected in the PSP-positive material. Hydrolysis was useful to confirm the identity of GTX5 and provided indicative information about C1 and C2 toxins in the PSP-positive material. The methods used in the second interlaboratory study showed sufficiently consistent analysis results to undertake a certification exercise to assign certified values for STX and dc-STX in lyophilized mussel.     

The Ministry of Environmental Protection Issued "Feasible Technology Guidelines for Pollution Prevention and Control in Wood Pulping Process of the Paper Industry (Trial)" and Two Other Guiding Technical Documents

On December 27t＂, 2013, the Ministry of Environmenta Protection announced that, in order to implement ＂The Environmental Protection Law of the People＇ s Republic of China＂, improve the working system in environmenta protection technologies, and promote technologica advancement in pollution prevention, the Ministry of Environmental Protection sponsored the formulation of three guiding technical documents including ＂Feasible Technology Guidelines for Pollution Prevention and Contro n Wood Pulping Process of the Paper Industry （Trial）＂     

1~(st) Intelli-Tissue~ EcoEc Tissue Machine Supplied by PMP Group Successfully Put into Operation in China

正On April 29th,2014,Intelli-Tissue EcoEc tissue machine supplied by PMP Group successfully put into operation at Hebei Xuesong Paper Co.,Ltd.,this is the first such kind of paper machine of PMP Group in China.