气相色谱-质谱法筛查测定浓缩果蔬汁中73种农药残留

对Qu ECh ERS前处理方法进行改进,建立了Qu ECh ERS结合固相萃取技术(SPE)作为样品前处理方法的浓缩果蔬汁中73种农药多残留的气相色谱-质谱(GC-MS)检测方法。样品用体积分数1%的醋酸乙腈溶液萃取,经Waters Sep-Pak Vac固相萃取柱净化,乙腈-甲苯(体积比为3∶1)洗脱后旋转蒸发浓缩,气相色谱-质谱分析。分别以定量限和4倍定量限浓度对橙汁、苹果汁、葡萄汁、白菜汁、胡萝卜汁5种空白浓缩果蔬汁样品进行添加回收率实验,方法的回收率为71.5%~103.1%,相对标准偏差为1.6%~19.8%。方法的检出限和定量限分别为0.005 0~0.075 0 mg/kg、0.016 7~0.250 0 mg/kg。该方法前处理简单快速、分析时间短,灵敏度、准确度和精密度均符合农药多残留检测技术的要求,适用于苹果汁、橙汁、葡萄汁、白菜汁、胡萝卜汁等浓缩果蔬汁中73种农药多残留的快速筛查与定量分析。     

QuEChERS-超高效液相色谱-串联质谱法测定桑叶中64种农药残留

目的建立Qu ECh ERS结合超高效液相色谱-串联质谱法测定桑叶中64种农药残留的方法。方法样品经乙腈提取,应用Qu ECh ERS方法进行净化处理。使用Cortecs T3 (2.1 mm×100 mm, 2.7μm)色谱柱,用含0.1%(V/V)甲酸溶液(A)和甲醇(B)为流动相进行梯度洗脱,采用电喷雾电离(electrospray ionization,ESI)和多离子检测模式(multiple reaction monitoring, MRM)进行检测,基质外标法定量。结果 64种农药在0.001~0.050 mg/L范围内线性良好,线性相关系数均大于0.999。在1~10μg/kg添加浓度范围内,回收率为78.0%~94.9%,相对标准偏差为1.1%~5.5%。结论该方法操作简单,灵敏度高,可用于桑叶中农药残留的高通量筛查。     

基于QuEChERS前处理技术的水产品中喹诺酮类药物多残留ELISA检测方法的建立

建立了水产品中3种喹诺酮类(恩诺沙星、环丙沙星、氧氟沙星)兽药多残留的新型Qu ECh ERS前处理技术结合酶联免疫快速检测的分析方法。基本流程为样品经90%乙腈(1%乙酸)均质提取离心后,上清液依次用C18净化、静置沉淀蛋白后用于测定,该前处理方法灵敏、快速、经济、实用性强。测试曲线线性范围为0.107~177.896ng/m L,检出限为0.0087μg/kg,IC50值为4.34ng/m L。样品批内和批间平均回收率分别为94.10%、93.70%,批内变异系数为4.09%~8.41%,批间变异系数2.78%~7.99%。检测结果与HPLC的相关系数R2=0.9897,表明酶联免疫检测方法及样品前处理方法适合喹诺酮类药物多残留检测。     

QuEChERS法和UPLC-MS-MS法快速测定稻谷中4种磺酰脲类除草剂的残留量

建立了Qu ECh ERS法-超高效液相色谱串联质谱法(UPLC-MS-MS)快速测定稻谷中氯磺隆、甲磺隆、苄嘧磺隆、醚磺隆4种磺酰脲类除草剂的方法。采用酸化乙腈超声提取,Qu ECh ERS法净化的方法处理稻谷样品,利用UPLC-MS-MS分析,在多反应监测(MRM)模式下以0.1%甲酸水和乙腈为流动相等度洗脱。4种除草剂在10~200μg/L范围内线性良好,相关系数在0.995~0.998之间,平均加标回收率为75.2%~113.3%,相对标准偏差在0.6%~8.3%之间。该方法适用于稻谷中4种除草剂残留的测定。     

超高效液相色谱-四级杆-飞行时间质谱法同时快速检测水产品中37种兽药残留

目的建立超高效液相色谱-四极杆-飞行时间质谱法快速检测水产品中磺胺类、喹诺酮类、四环素类、硝基咪唑类、大环内酯类、β-内酰胺类、三苯甲烷类7类37种兽药残留的方法。方法样品采用Qu ECh ERS方法(quick,easy,cheap,effective,rugged and safe method)进行前处理(用乙腈提取,提取液经Al_2O_3吸附剂净化);采用ZORBAX SB-C_(18)色谱柱(100 mm×2.1 mm,3.5μm)分离,以乙腈-5 mmol的乙酸铵为流动相,梯度洗脱,Q-TOF-MS电喷雾正离子模式分析检测;在全扫描采集模式下,以准分子离子峰的峰面积定量,以化合物的色谱保留时间和精确质量数定性。结果各化合物在0.5~2000μg/kg范围内均呈现良好的线性关系,相关系数均大于0.99。样品平均添加回收率为67%~109.5%,相对标准偏差(RSD)均小于15.3%(n=6)。结论方法简单、快速、可靠,可用于水产品中兽药多残留的快速筛查。     

液相色谱-串联质谱结合谱库检索测定猪组织中13种氟喹诺酮类药物

采用MRM→IDA→EPI→谱库检索模式建立了猪组织中13种氟喹诺酮类药物的液相色谱-电喷雾串联质谱多残留检测方法,结合谱库检索功能同时实现了定性定量分析.组织样品经N,N-二甲基甲酰胺-乙腈混合溶液提取,Waters HLB柱净化,本方法13种氟喹诺酮类药物的线性范围为1.0～5000.0 μg/kg,线性相关系良好...     

QuEChERS-超高效液相色谱-串联质谱法同时快速测定肉类食品中多种抗生素残留

目的建立能同时检测肉类食品中20种磺胺和8种喹诺酮类抗生素残留的Qu ECh ERS-超高效液相色谱-串联质谱法(UPLC-MS/MS)。方法样品加1%甲酸乙腈提取,经分散固相萃取净化后,采用Waters C18(2.1 mm×100 mm,1.7μm)色谱柱分离,梯度洗脱,采用电喷雾-正离子多反应监测模式,外标法定量。结果 28种抗生素在各自浓度范围内线性关系良好,相关系数(r)为0.997 5~0.999 6,检出限(LOD)为0.17~0.91μg/kg(S/N=3),磺胺类抗生素回收率在70.9%~115.2%之间,RSD在2.8%~15.9%(n=6)之间;喹诺酮类抗生素回收率在71.3%~112.3%之间,RSD在2.5%~14.6%(n=6)之间。结论建立的方法准确、快速、灵敏度高,可对动物源性食品中多种抗生素残留进行快速分析。     

超高效液相色谱-串联质谱法同时测定鳗鱼中32种兽药残留

目的 建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)同时测定鳗鱼中13种磺胺类、15种喹诺酮类和4种四环素类兽药残留的分析方法。方法 鳗鱼试样采用乙二胺四乙酸二钠(ethylenediaminetetraacetic acid disodium salt, Na2EDTA)-Mcllvaine提取液进行提取, HLB固相萃取柱净化, Waters ACQUITY UPLC BEH C18色谱柱分离, 以0.1%甲酸乙腈和0.1%甲酸水溶液作为流动相进行梯度洗脱; 电喷雾正离子模式下, 以多反应监测(multiple reaction monitoring, MRM)方式采集数据进行定性与定量分析, 外标法定量。结果 磺胺类、喹诺酮类及四环素类药物分别在2~50、2~50、5~100 μg/kg浓度范围内线性相关性良好, 相关系数均大于0.99; 不同加标水平的平均回收率为82.6%~110.2%, 相对标准偏差(relative standard deviations, RSDs)为3.2%~13.9%, 检出限(limits of detection, LODs)和定量限(limits of quantification, LOQs)分别为0.3~2.0 μg/kg和1.0~5.0 μg/kg。结论 本方法快速简便、灵敏可靠, 适合大批量鳗鱼中同时快速对磺胺类、喹诺酮类及四环素类兽药残留进行定性和定量检测。     

QuEChERS萃取-液相色谱法测定酱油和酱制品中三氯蔗糖

建立了Qu ECh ERS萃取-液相色谱法测定酱油和酱制品中三氯蔗糖含量的分析方法。样品以乙腈作为萃取溶剂,采用改进的Qu ECh ERS方法进行萃取。以乙腈和水为流动相,C18色谱柱分离,液相色谱-蒸发光散射检测器进行检测。三氯蔗糖在20～1 500μg/m L呈良好线性关系,相关系数(r2)> 0. 99; 3个水平下的加标回收率为83. 2%～95. 4%;相对标准偏差(RSD)为4. 1%～6. 3%;方法检出限为1 mg/kg,定量限为3 mg/kg;方法简单、快速、准确可靠,适用于酱油及酱制品中三氯蔗糖的快速检测。     

同位素内标-超高效液相色谱串联质谱法测定禽类食品中喹诺酮与四环素残留量

摘 要：目的 建立测定禽类食品中11种喹诺酮与4种四环素兽药残留的超高效液相色谱-串联质谱(ultra performance liquid chromatography-tandem mass spectrometry，UPLC-MS/MS)分析方法。方法 鸡肉和鸡蛋样品经Mcllvaine-Na2EDTA缓冲液提取，7%钨酸钠溶液沉淀蛋白，HLB柱净化后，喹诺酮类药物采用10 mmol/L乙酸铵(含0.1%甲酸，v/v)与甲醇为流动相，四环素类药物采用0.1%甲酸与乙腈为流动相。两种类型药物均采用电喷雾电离，正离子扫描，多离子反应监测模式，基质匹配同位素内标，标准曲线法定量。结果 15种兽药残留在0.1~50.0 μg/L的浓度范围内线性良好，相关系数r2均大于0.9927，检出限范围为0.05~0.20 μg/kg，平均回收率为60.6％~117.9％，相对标准偏差范围为0.51%~15.3%。采用建立的方法检测安徽省市售2016~2018年的鸡肉和鸡蛋样品中喹诺酮与四环素残留，检测结果通过食品安全指数(international foundation for science ，IFS)评估，发现鸡肉和鸡蛋中喹诺酮类IFS均值分别为0.00048 μg/kg?bw?d与0.000097 μg/kg?bw?d，四环素类IFS均值分别为0.00073 μg/kg?bw?d与0.00098μg/kg?bw?d，均小于1，说明其膳食暴露风险较低。结论 该方法的样品前处理沉淀蛋白完全，净化效果好，减少了基质效应的影响，适用于大批量禽类食品中喹诺酮与四环素兽药残留量的快速测定。     

Probiotics and prebiotics--perspectives and challenges

Owing to their health benefits, probiotics and prebiotics are nowadays widely used in yogurts and fermented milks, which are leader products of functional foods worldwide. The world market for functional foods has grown rapidly in the last three decades, with an estimated size in 2003 of ca US$ 33 billion, while the European market estimation exceeded US$ 2 billion in the same year. However, the production of probiotics and prebiotics at industrial scale faces several challenges, including the search for economical and abundant raw materials for prebiotic production, the low-cost production of probiotics and the improvement of probiotic viability after storage or during the manufacturing process of the functional food. In this review, functional foods based on probiotics and prebiotics are introduced as a key biotechnological field with tremendous potential for innovation. A concise state of the art addressing the fundamentals and challenges for the development of new probiotic- and prebiotic-based foods is presented, the niches for future research being clearly identified and discussed.     

常用消毒灭菌法及其机理与应用

介绍了采用消毒灭菌方法,有加热消毒法,紫外线辐射法和化学药剂消毒法。常用化学药剂有醛类、含氯消毒剂、醇类消毒剂以及高锰酸钾、生石灰等,阐释了消毒与灭菌两个概念的区别。     

European citizen and consumer attitudes and preferences regarding beef and pork

This paper presents the combined mid-term findings of the consumer research components of two EU Sixth Framework Programme integrated projects concerning meat, ProSafeBeef and Q-PorkChains. The consumer pillar of ProSafeBeef carried out eight focus group discussions in May 2008, in France, Germany, Spain and the UK. Q-PorkChains conducted a large-scale, web-based, consumer survey in January 2008 in Belgium, Denmark, Germany, Greece and Poland. The first project provides a set of qualitative data from a small cohort of focus groups and the second a set of quantitative data from a larger consumer sample. This paper draws together the main findings of both projects and provides a comprehensive overview of European citizens’ and consumers’ attitudes towards and preferences regarding beef and pork. In general, consumers consider meat to be a healthy and important component of the diet. Consumers support the development of technologies that can improve the health attributes of meat products and guarantee eating quality, but they have a negative view of what they see to be excessive manipulation and lack of naturalness in the production and processing of beef products. In the Q-PorkChains study consumer and citizen segments are identified and profiled. Consumer segments were built upon the frequency and variety of pork consumption. The citizen segments were built upon their attitudes towards pig production systems. Overall, the relationship between individuals’ views as citizens and their behaviour as consumers was found to be quite weak and did not appear to greatly or systematically influence meat-buying habits. Future studies in both projects will concentrate on consumers’ acceptance of innovative meat product concepts and products, with the aim of boosting consumer trust and invigorating the European beef and pork industries.     

Heritability and correlations for body condition score and dairy form within and across lactation and age

The objectives of the current study were to investigate the relationship between body condition score (BCS) and dairy form and changes in genetic parameters for BCS and dairy form within and across lactations and age. Body condition score and dairy form were obtained from the Holstein Association USA, Inc. Records were edited to include those cows classified between 24 and 60 mo of age and between 0 and 335 d in milk (DIM). A minimum of 20 daughters per sire and 15 cows per herd-classification visit were required. The dataset consisted of 135,178 records from 119,215 cows. Repeatability, multiple trait, and random regression models were used to analyze the data. All models included fixed effects for herd-classification visit, age within lactations 1, 2, and 3 or higher, and 5th-order polynomials for DIM. Random effects included sire and permanent environment for all models. Random regression models included age at classification nested within sire or DIM and lactation number nested within sire. Genetic variance for both BCS and dairy form was lowest in early lactation and highest in midlactation. Genetic correlations within and across lactations were high. The genetic correlation between DIM 0 in lactation 1 and DIM 305 in lactation 3 was estimated to be 0.77 for BCS and 0.60 for dairy form. The genetic correlation estimate between 30 mo of age at classification and 50 mo of age at classification was 0.94 for both dairy form and BCS. The repeatability models appeared to generate accurate evaluations for BCS or dairy form at all ages and stages of lactation.     

原花色素及其开发应用

对原花色素的结构、化学特性、制备、分析方法、应用前景作一综述,并重点讨论其生理功能,为在功能性食品、药物、化妆品等领域的深入研究和开发提供参考。     

组学技术与果蔬采后质量和安全控制

果蔬可以提供营养, 有利于人类健康, 而果蔬的后熟及其与环境的相互作用会影响果蔬采后的质量和安全。对果蔬生物学过程的了解和掌握是减少果蔬采后损失和保障果蔬采后质量和安全的关键。在过去的10多年, 基于组学技术的系统生物学在了解果蔬后熟及其与环境相互作用的分子机制方面得到了越来越多的应用。本文对此做了细致的总结, 指出了存在的不足, 并提出了未来的发展方向。     

天然香精香料与生物技术

天然香精香料是高价值的精细化工产品和食品添加剂,但原料来源有限且提取成本高。利用生物技术生产这类产品具有广阔的前景。简述了发酵工程、酶工程、细胞工程和基因工程在香精香料中的应用,并探讨了生物技术在香精香料中的应用前景。     

Dioxins and PCBs in ostrich meat and eggs: levels and implications

ABSTRACT

Although consumption of eggs is an essential part of our diet, limited information is available for table eggs other than those laid by hens. The aim of our study was to determine concentrations of polychlorinated dibenzofurans (PCDD/Fs), dioxin-like (DL-) and non-dioxin-like (NDL) polychlorinated biphenyls (PCBs) in ostrich eggs and meat available on the Polish market, in order to obtain baseline information on the current status of these pollutants in comparison to poultry products. Obtained data were compared with the binding EU limits set for chicken eggs and meat. The levels of individual PCDD/Fs and PCBs congeners varied considerably. The percentage share of total WHO toxic equivalency factor (WHO-TEQ) content indicates the dominant role of PCDD/Fs. High concentrations of PCDD/F and DL-PCBs, in the range of 0.85–74.48 pg WHO-TEQ g^?1 fat, were found in ostrich eggs; this exceeds the maximum level permitted for chicken eggs by a factor of up to 15. Eight of the 11 egg samples exceeded the action level for hen eggs. Although the ostrich meat concentrations of PCDD/Fs do not exceed the limit established for poultry muscle (1.75 pg g^?1 fat), average contents of PCDD/Fs exceeded almost four times the levels in chicken and turkey muscle. Human exposure was evaluated and the resulting risk was characterised. Taking into account the low average consumption of ostrich eggs, the resulting exposure to dioxins for the general population can be considered as negligibly low. However, the individuals who frequently consume such eggs may be at risk of elevated exposure. Although ostrich products are not consumed frequently, such data are nevertheless useful for food safety purposes.     

毛霉型低盐速成豆豉工业化生产工艺与设备

本文介绍了毛霉型低盐速成豆豉的工业化生产工艺及生产线的关键设备。     

Phenolic composition and nutraceutical properties of organic and conventional cinnamon and peppermint

Conventional and organic cinnamon and peppermint were investigated for their phenolic profile, anti-proliferative, anti-inflammatory, and antioxidant properties. Accelerated solvent extraction with 75% acetone was used to extract samples. Caffeic acid was the most abundant phenolic acid in peppermint. Catechin, (−)-epigallocatechin gallate, syringic acid, gallic acid, vanillic acid, and p-coumaric acid were also detected in both spices. There was no significant difference between conventional and organic spices in the composition of most individual phenolics. All conventional and organic peppermint and cinnamon extracts exhibited strong anti-proliferative and anti-inflammatory properties. Cinnamon was more efficient in inhibiting IL-1β and COX-2 expression, while peppermint showed better inhibitory effect on IL-6 and MCP-1. This study indicates that cinnamon and peppermint may potentially be used as dietary sources of bioactive phytochemicals for improving health.