HPLC法同时测定植物样品中3种甾醇含量

建立高效液相色谱法(HPLC)同时测定植物样品中麦角甾醇、胆甾醇和豆甾醇的方法。样品经皂化、萃取后,用紫外检测器进行测定。优化后的色谱条件为:Shim-pack CLC ODS色谱柱(250 mm×4.6 mm, 5.0μm);流动相采用纯甲醇;检测波长205 nm和282 nm,流速1.0 mL/min;柱温35℃;进样量10μL。检测方法显示, 3种甾醇在1.00～200 mg/L的线性范围内相关系数R~20.999,方法精密度RSD0.5%(N=6),在加标浓度为20.0～200 mg/kg条件下,加标回收率93.6%～103.4%(N=6),检出限(S/N=3) 3.0～6.0 mg/kg,定量限(S/N=10) 10～20 mg/kg。     

大豆油脱臭馏出物中α、β、γ、δ-生育酚4种异构体的HPLC测定

建立了大豆油脱臭馏出物中α、β、γ、δ-生育酚4种异构体的简便、准确、快速的HPLC分析方法。选用NucleosilNH2柱正相分离,以正己烷-异丙醇(98∶2)为流动相,在280nm波长进行检测,获得了较理想的分离效果。该方法线性范围宽(0.015～1.7μg),回收率范围为99%～103%,信噪比(S/N)为3时最低检测限为3.5×10-5μg。     

高效液相色谱法测定纺织品中喹啉的含量

文章建立了一种测定纺织品中喹啉的液相色谱(HPLC)分析方法。方法以甲醇超声提取样品,C18色谱柱分离,流动相为甲醇/水(60∶40,v∶v),检测波长为225 nm。实验结果表明,该方法定量限(S/N=10)为3.0 mg/kg,在3.0、6.0、30.0 mg/kg添加水平下的回收率为82.5%～99.9%,相对标准偏差为1.9%～6.1%。该方法快速简便,回收率高,精密度好,能够满足纺织品中喹啉的检测要求。     

液相色谱荧光法测定食品中乙氧基喹残留量

建立检测多类食品中乙氧基喹残留量的液相色谱荧光法。方法 样品在碱性条件下用正己烷提取,经调节酸碱度液液萃取净化后进行检测。采用Agilent Eclipse XDB-C18柱(150mm×4.6mm,5μm)色谱分离,甲醇-水为流动相进行线性梯度洗脱,流速为1.0ml/min,柱温30℃,进样量20μl;荧光检测器激发波长365nm,发射波长425nm。结果 乙氧基喹在0.05～10mg/L范围内线性关系良好(r=0.9992),方法的检出限(S/N=3)为7.5μg/kg,定量限(S/N=10)为25μg/kg;8类食品基质分别添加3个不同浓度水平,平均回收率为80.5%～95.9%,RSD为3.1%～11.5%(n=8)。结论 本方法实用性强,可操作性好,适用于多类食品中乙氧基喹残留量的检测。     

高效液相色谱法测定纸质食品接触材料中双酚A和双酚S的含量

该文建立一种测定纸质食品接触材料中双酚A和双酚S含量的高效液相色谱（high performance liquid chromatography,HPLC）法。方法分析采用 Thermal Ultimate 3000SD 液相色谱仪,ZORBAX Eclipse XDB-CN（250 mm×4.6 mm,5 μm）反相柱。流动相为甲醇/水（体积比 1∶1）,等度洗脱,流速 0.8 mL/min;二极管阵列（diode array detector,DAD）检测器,检测波长280 nm和259 nm。结果表明,在1 mg/L～50 mg/L浓度范围内,双酚A和双酚S的浓度与峰面积呈现良好的线性关系,相应的线性相关系数均≥0.999 8,双酚A和双酚S的检出限和定量限分别为0.10、0.02 mg/L和0.50、0.10 mg/L。方法验证过程中做了低、中、高3个水平的添加回收,平均回收率为85.2%～103.0%,相对标准偏差（relative standard deviation,RSD）均小于 5%。     

一种快速测定蒽醌含量的可见光谱方法

介绍了一种快速测定蒽醌含量的可见光谱方法。本方法是基于用连二亚硫酸钠(Na2S2O4)在碱性条件下将蒽醌(AQ)还原成蒽氢醌(AHQ),然后在505 nm处检测AHQ的吸光度而建立的。结果表明,将AQ转化成AHQ的最佳还原条件为:温度80℃,时间10 min,AQ、Na2S2O4和NaOH的摩尔比为1∶3∶50。本方法的相对标准偏差为2.01%;定量检测极限为2.26 mg/L;回收率在95.5%～100%。本方法完全满足商品蒸煮助剂中AQ含量检测的要求。     

绿豆、红小豆和黑豆种皮18 种元素分析

为全面了解绿豆皮、红小豆皮和黑豆皮的18 种元素含量,充分开发利用豆皮资源,提高豆类加工产品
的附加值,用元素分析（elemental analyzer,EA）仪和电感耦合等离子体发射光谱（inductively coupled plasmaatomic
emission spectrometer,ICP-AES）仪测定了3 种豆皮的N、C、S、Ca、Mg、K、P、Na、B、Ba、Co、
Cr、Cu、Fe、Mn、Ni、Zn和Sr元素含量。结果表明,EA仪测定豆皮中N、C和S方法检出限为32～96 μg/g,回收
率为97%～115%,相对标准偏差为0.20%～2.63%（n=5）;ICP-AES测定豆皮中Ca、Mg、K、P、Na、B、Ba、
Co、Cr、Cu、Fe、Mn、Ni、Zn和Sr元素方法检出限为0.02～152 μg/g,回收率为84%～118%,相对标准偏差为
0.44%～4.46%（n=5）。黄豆标准物N、Mg、P、B、Ba、Co、Cr、Mn、Ni、Zn和Sr元素测定值在推荐范围内,
S、Ca、K、Na、Cu和Fe元素测定值接近推荐值。分析方法快速、简便,达到了应用的要求。     

荧光法鉴定柑桔汁饮料掺假

用荧光光度计调查了35个品种柑桔原汁的荧光特性,结果表明,这些柑桔汁具有相同的荧光吸收,最大激发波长平均值为288.8nm,变化范围284.6～296.5nm,最大发射波长348nm。原汁用水稀释至1%时,荧光强度的平均值为65.94nm(25℃),该方法至少可检测出0.5%原汁。本文提出用检查柑桔汁饮料激发光谱在280～300nm有无最大吸收作为判定饮料中有无原汁的方法。模拟柑桔汁饮料在280～300nm无吸收,将此方法应用于实际工作中,效果很好。该法快速、灵敏、简单、准确。     

高效液相色谱法测定皮革中的双酚A、双酚F和双酚S

建立了一种测定皮革中双酚A、双酚F和双酚S含量的分析方法。皮革样品经甲醇超声提取、旋转蒸发仪浓缩后,在277 nm波长条件下,使用高效液相色谱仪进行分析,经二极管阵列器检测,甲醇-水溶液洗脱后,外标法进行定量。结果显示,双酚A、双酚F和双酚S在1 mg·L^-1～30 mg·L^-1的范围内线性相关系数均大于0.9995,检出限均小于0.64 mg·kg^-1,高、中、低三个水平加标回收率范围为85.8%～97.1%,相对标准偏差为0.11%～2.22%,满足检测要求。     

改进铬天青S光度法测定饮用天然矿泉水中铝

采用分光光度法研究了铬天青S(CAS)-溴化十六烷基吡啶(CPB)-聚乙二醇辛基苯醚(OP)-铝(Al)四元络合物的显色反应,并确定了最佳试验条件.结果表明:显色反应在pH 7.0的HAc-NaAc缓冲溶液中进行,此时最大吸收波长位于630nm处,最佳显色时间为20min.回归方程为y=0.2235x+0.2549,相关系数r=0.9995,改进后的方法测定天然饮用矿泉水中铝的含量,相对标准偏差为3.36%～3.77%,回收率为99.2%～100.1%     

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。     

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.     

益生素、益生菌与结肠癌

介绍了益生素和益生菌及其作用机理。在动物模型中，有大量的数据证实益生素和益生菌能够预防癌症．而在人体内还没有直接实验证据。它们抑制癌症的确切机理目前尚不清楚，其抑制机理可能是：肠道菌群代谢活动的改变，肠道理化环境的改变，潜在的致癌物质的黏附和降解，肠道菌群的改变、抗癌或抗诱变物质的形成、提高宿主的免疫应答、影响宿主的生理活动以及发酵不能被消化的食物并形成有益代谢产物。     

节能节水型印染助剂和设备的现状

从节能、节水、缩短工艺流程和环保的角度出发，介绍了国内外研制开发的一系列新型节能、节水型印染助剂和染整设备。     

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。     

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。     

酚类物质的结构与性质及其与葡萄及葡萄酒的关系

酚类物质是一类大而复杂的化合物。葡萄与葡萄酒中常见的酚类物质可分为类黄酮和非类黄酮两大类，它们是葡萄中重要的次生代谢产物，与葡萄的抗病性、采后生理、贮存、保鲜等密切相关。葡萄酒中的酚类物质来自于葡萄果实、果梗、酵母代谢以及橡木桶，参与形成葡萄酒的味道、骨架、结构和颜色等，对红葡萄酒的特征和质量尤其重要。     

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。