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1.
建立采用固相萃取净化,高效液相色谱法测定鸡蛋中三聚氰胺含量的方法。样品采用三氯乙酸和乙酸铅溶液提取,优化样品提取时间、色谱柱及固相萃取柱,最终确定为样品提取20min、采用TC-C18(4.6mm×150mm,5μm)色谱柱和PCX固相萃取柱。采用紫外检测器,检测波长为240nm,流动相为乙腈:辛烷磺酸钠-柠檬酸缓冲液(10:90,V/V),流速1.0mL/min,进样量20μL,外标法定量。三聚氰胺在1~50μg/mL范围内,具有良好的线性关系(R2=1),在添加质量浓度为5~20mg/kg范围内,三聚氰胺添加回收率在72.8%~87.6%,RSD(n=6)为1.5%~4.0%,最低检测限为0.54mg/kg。  相似文献   

2.
目的建立超高效液相色谱-串联质谱测定芹菜和土壤中灭蝇胺及其代谢物三聚氰胺残留的分析方法。方法样品以甲醇:水=4:1(V:V)混合溶液提取,经混合阳离子固相萃取柱净化,亲水作用色谱柱分离,以10mmol/L乙酸铵溶液和乙腈作为流动相进行梯度洗脱,通过电喷雾离子源正离子检测模式和多重反应监测模式测定,同位素内标法定量。结果灭蝇胺和三聚氰胺在0.01~1.0 mg/L范围内线性关系均较好,检出限为8.16×10–6~6.91×10–5 mg/kg,在0.01、0.1和1.0 mg/kg 3个添加水平下,方法回收率在81.96%~108.81%,相对标准偏差为2.83%~6.19%(n=5)。结论该方法简单、快速、准确,适合用于芹菜和土壤中灭蝇胺及其代谢物三聚氰胺的定性和定量检测。  相似文献   

3.
李曼  李荣  谭津  姜子涛 《食品工业科技》2012,33(13):311-315
建立了同时分析液态奶、自来水和游泳池水中三聚氰胺和三聚氰酸的钛胶正相高效液相色谱法。色谱条件:分离柱为Titania Sachtopore-NP柱(250mm×4.6mm×5μm),流动相为水∶甲醇=50∶50(V/V)、流动相中含醋酸盐1.0mmol/L、pH7.0、流速0.8mL/min、柱温60℃、UV检测波长210nm。三聚氰胺和三聚氰酸分别在0.1~10μg/mL和2~100μg/mL范围内与对应的峰面积呈良好的线性关系,检出限分别为0.02μg/mL和0.1μg/mL,本方法三聚氰胺的回收率为94.8%~111.7%,三聚氰酸回收率为103.9%~114.3%,三聚氰胺和三聚氰酸测定结果的相对标准偏差分别为0.62%和0.78%(n=8)。  相似文献   

4.
杨嘉  丁娟芳  周元元  徐秋  朱姜  王帅 《食品科学》2014,35(6):172-175
建立高效液相色谱-二极管阵列检测器同时检测乳粉中三聚氰胺和双氰胺的分析方法。采用1%三氯乙酸溶液提取样品中的三聚氰胺和双氰胺,氨基柱为分析柱,流动相为乙腈-水(75∶25,V/V),流速1.0 mL/min,检测波长233 nm。2 种物质在0.005~60 mg/L范围内与其峰面积线性关系良好,不同添加水平的回收率在83.2%~102.6%,三聚氰胺和双氰胺的方法定量限分别为0.17、0.15 mg/kg,方法变异系数为2.3%~7.2%(n=6)。此方法操作简便、快速、成本低,适用于乳粉中三聚氰胺和双氰胺的同时检测。  相似文献   

5.
建立了固相萃取-高效液相色谱法测定牛奶及蛋白类饮料中10种防腐剂的检测方法。方法采用乙腈提取、沉淀后,滤液经PEP-SPE固相萃取柱净化,采用Plus C18柱:5μm,4.6 mm×250 mm;流动相:乙腈:0.01 moL/L磷酸二氢钾溶液(pH=4.0)(梯度洗脱)。流速:1.0 mL/min;检测波长230 nm和254 nm;柱温30℃;进样量10μL。该方法的检出限在1.0 mg/L~2.0 mg/L,线性范围1.0 mg/L~100.0 mg/L,牛奶加标回收率在93.7%~114.4%,相对标准偏差在0.59%~4.84%(n=4)。乳饮料加标回收率在68.2%~108.1%,相对标准偏差在0.20%~4.92%(n=4)。植物蛋白饮料加标回收率在92.0%~113.3%,相对标准偏差在0.03%~3.18%(n=4)。该方法简单、快速、灵敏度高,并具有良好的精密度与准确度,可作为牛奶、蛋白类饮料中检测这10种防腐剂的有效定量方法。  相似文献   

6.
建立了固相萃取-高效液相色谱法测定食品中脱氢乙酸的方法。方法采用C18(5μm,4.6mm×250mmi.d)反向色谱柱,流动相:V(甲醇)∶V(0.02mol/L乙酸铵溶液)=7∶93,流速1.0mL/min,检测波长290nm,柱温30℃,进样量5μL。该方法的检出限在1.5~4.8mg/kg,线性范围0.01~0.08mg/mL,相对标准偏差(RSD)0.95%~2.10%(n=6),加标回收率94.5%~100.4%。该方法简单、快速、灵敏度高,并具有良好的精密度与准确度,可作为食品中检测脱氢乙酸的有效定量方法。  相似文献   

7.
离子交换色谱-紫外检测法测定乳制品中三聚氰胺   总被引:11,自引:0,他引:11  
建立离子交换色谱-紫外检测法测定乳制品中三聚氰胺。样品直接用水和乙腈提取,分析时用LC-SCX离子交换色谱柱分离,浓度为0.05 mol/L磷酸二氢钾溶液(pH值为3.0)-乙腈(70∶30)为流动相,流速1.0 mL/min,在紫外波长240 nm下检测。三聚氰胺在0.5~100.0 mg/L的范围内,质量浓度与色谱峰面积呈良好的线性关系(r=0.9999),最低检出限为1.0 mg/kg,加标回收率在93.8%~102.5%范围内,相对标准偏差(RSD)小于3.5%。该方法简便、快速、准确,能够满足检测要求。  相似文献   

8.
刘菊  郑婷  常诚  刘霞  张薇薇  施超欧 《食品科学》2010,31(14):264-267
采用反相离子对色谱法、亲水相互作用色谱法及阳离子交换色谱法测定奶粉中三聚氰胺的含量。奶粉样品前处理采用水- 乙酸提取后过RP柱和甲酸提取后乙腈沉淀两种方法,反相离子对色谱法采用C18 柱和10mmol/L庚烷磺酸钠与10mmol/L 柠檬酸的缓冲溶液- 乙腈(85:15,V/V)的流动相;亲水相互作用色谱法采用HILIC 柱和20mmol/L甲酸胺- 乙腈(10:90,V/V)的流动相;阳离子交换色谱法采用IonPac CS17 阳离子交换柱和6mmol/L 硫酸的流动相。流速1.0mL/min,检测波长240nm。结果表明,3 种方法测定三聚氰胺在0.1~25.0mg/L 范围内线性均很好(r=1.0000),样品加标回收率在93.91%~99.96% 范围内。3 种方法中,反相离子对色谱法对三聚氰胺的响应值最高,阳离子交换色谱法则能用最短的时间检测出三聚氰胺,而亲水相互作用色谱法在假阳性的判断上可作为其他两种方法的补充。  相似文献   

9.
以双氰胺为内标物,采用高效液相色谱内标法测定奶粉中三聚氰胺的含量,通过对色谱条件的优化,最后确立了有效的检测方法。样品经20 mL 50 ℃热水,0.5g无水硫酸镁,10 mL乙腈提取后,采用Nova-Pak C18色谱柱(3.9 mm×15 mm×5 μm)分离,以0.01 mol/L乙酸铵∶乙腈= 90∶10(V∶V)作为流动相,218 nm为检测波长。结果表明,双氰胺在该条件下能够与三聚氰胺完全分离,可以作为测定三聚氰胺的内标物。在0.500~1.500 mg/kg的添加范围内,三聚氰胺的回收率为98.2%~100.5%。精密度实验结果相对标准偏差为0.44%。所测定奶粉样品中三聚氰胺为0.223 mg/kg。此法处理样品处理简便易行,回收率、准确度高,分析速度快,具有良好的重复性和再现性,适于测定奶粉中的三聚氰胺。  相似文献   

10.
研究建立利用加压毛细管电色谱(p CEC)测定乳及乳制品中三聚氰胺的分析方法。样品采用2%三氯乙酸水溶液超声提取,阳离子固相萃取柱(MCX)净化,提取液经C18反相毛细管电色谱柱分离,流动相乙腈-10 mmol/L辛烷磺酸钠溶液(p H 3.0)=15+85,泵流速0.05 m L/min,分离电压-2 k V,紫外检测器240 nm检测。该方法在1.0 mg/kg~100 mg/kg质量浓度范围内线性关系良好(R2=0.999),在牛奶和酸奶中的定量限为2.5 mg/kg,在奶粉中的定量限为10 mg/kg,加标回收率为78.9%~93.5%,相对标准偏差小于5%。  相似文献   

11.
常用消毒灭菌法及其机理与应用   总被引:3,自引:0,他引:3  
傅金泉 《酿酒科技》1999,(2):97-99,101
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。  相似文献   

12.
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.  相似文献   

13.
益生素、益生菌与结肠癌   总被引:1,自引:0,他引:1  
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。  相似文献   

14.
节能节水型印染助剂和设备的现状   总被引:1,自引:0,他引:1  
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。  相似文献   

15.
毛霉型低盐速成豆豉工业化生产工艺与设备   总被引:1,自引:0,他引:1  
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。  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
原花色素及其开发应用   总被引:9,自引:0,他引:9  
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。  相似文献   

19.
酚类物质的结构与性质及其与葡萄及葡萄酒的关系   总被引:20,自引:0,他引:20  
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。  相似文献   

20.
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。  相似文献   

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