共查询到20条相似文献,搜索用时 16 毫秒
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In‐Seek Jeong Byung‐Man Kwak Jang‐Hyuk Ahn Donggil Leem Taehyung Yoon Changyong Yoon Jayoung Jeong Jung‐Min Park Jin‐Man Kim 《Journal of food science》2012,77(10):C1042-C1046
Abstract: In this study, nonheated saponification was employed as a novel, rapid, and easy sample preparation method for the determination of cholesterol in emulsified foods. Cholesterol content was analyzed using gas chromatography with a flame ionization detector (GC‐FID). The cholesterol extraction method was optimized for maximum recovery from baby food and infant formula. Under these conditions, the optimum extraction solvent was 10 mL ethyl ether per 1 to 2 g sample, and the saponification solution was 0.2 mL KOH in methanol. The cholesterol content in the products was determined to be within the certified range of certified reference materials (CRMs), NIST SRM 1544 and SRM 1849. The results of the recovery test performed using spiked materials were in the range of 98.24% to 99.45% with an relative standard devitation (RSD) between 0.83% and 1.61%. This method could be used to reduce sample pretreatment time and is expected to provide an accurate determination of cholesterol in emulsified food matrices such as infant formula and baby food. Practical Application: A novel, rapid, and easy sample preparation method using nonheated saponification was developed for cholesterol detection in emulsified foods. Recovery tests of CRMs were satisfactory, and the recoveries of spiked materials were accurate and precise. This method was effective and decreased the time required for analysis by 5‐fold compared to the official method. 相似文献
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目的建立溶剂提取-阴离子交换树脂分离-氢化物发生原子荧光光谱法测定食品中无机砷、一甲基胂(MMA)和二甲基胂(DMA)的方法。方法以水-甲醇为提取剂,阴离子交换树脂分离,HG-AFS检测。结果方法检出限以砷计分别为:无机砷(As(Ⅲ) As(Ⅴ))0·34μg/L、MMA0·57μg/L、DMA0·46μg/L;20μg/L砷标准偏差为:无机砷2·45%、MMA3·34%、DMA4·96%。在0~50μg/L砷量范围校正曲线线性关系良好。试样加标回收率为:无机砷95·40%~97·00%,MMA97·80%~104·80%,DMA104·23%~107·50%。结论对海带、紫菜等海产品及大米等食品的检测,证明该方法简便易行。 相似文献
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烹调食品中杂环胺检测的样品前处理方法研究 总被引:1,自引:0,他引:1
杂环胺作为一类在烹调过程中产生的强致癌,高突变活力的物质,越来越受到科研工作者的关注。本文主要对食品中杂环胺检测的前处理技术进行了综述,介绍了从不同样品基质中进行提取和预浓缩的分析策略,如常用的液液萃取,液固萃取,固相萃取,在线串联液液萃取和固相萃取等前处理方法,重点讨论了在样品处理过程中的吸附剂和溶剂选择的问题,讨论了分析技术所需要的条件和最能达到准确结果的方法。 相似文献
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蒽酮法测定红枣可溶性糖含量条件的优化 总被引:4,自引:0,他引:4
以红枣为试材,通过单因素试验研究反应温度、蒽酮质量浓度、蒽酮用量、显色反应时间、冷却时间对红枣可溶性糖含量测定的影响,并采用正交试验优化测定红枣可溶性糖含量的最佳反应条件。结果表明,红枣可溶性糖含量测定的最佳条件为:蒽酮质量浓度25 mg/mL、蒽酮试剂用量3 mL、室温反应时间1 min、冷却时间25 min。该方法操作简便、快速、灵敏度高。验证实验结果表明,蔗糖标准液含量在20~240 μg/mL范围内有较好的线性关系(A=0.004 5C-0.013 4,相关系数为R2=0.999 2,式中,A为吸光度;C为糖含量)。实验重现性好,相对标准偏差(relative standard deviation,RSD)为0.20%(n=3);平均回收率达102.87%,RSD为0.84%(n=3)。最佳优化条件下测得的红枣可溶性糖含量为68.43%(以干质量计)。 相似文献
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Yoko Kitagawa Masahiro Okihashi Satoshi Takatori Keiji Kajimura Hirotaka Obana Masakazu Furuta Toshimasa Nishiyama 《Food Analytical Methods》2014,7(5):1066-1072
A rapid and simple method has been developed for the determination of 2-alkylcyclobutanone, 2-dodecylcyclobutanone (DCB), and 2-tetradecylcyclobutanone (TCB) in irradiated meat and processed foods. The procedure consists of extraction with n-hexane, following defatting and cleanup with a silica gel mini-column before gas chromatograph–mass spectrometry analysis. The method was evaluated using samples of beef, pork, Parmesan cheese, fried chicken, hamburger, gyoza (Chinese dumplings), and gyudon (boiled beef and onion seasoned with soy sauce and sugar). The recoveries of spiked DCB were 67–88 %, and those of TCB were 70–86 %. Furthermore, the method could detect DCB and TCB from samples irradiated at 1.0 and 2.6 kGy at levels dependent on dose; DCB and TCB were not detected in any nonirradiated samples. The method did not require special equipment, such as Soxhlet extraction, accelerated solvent extraction, or supercritical fluid extraction, for sample preparation. Thus, this method would be useful for determining DCB and TCB levels in irradiated meat and processed foods. 相似文献
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国标《GB/T 5009.92-2003食品中钙的测定》中滴定法(EDTA法)的测定应用起来有一定困难,故将其优化。将湿法消化改为干法消化,将掩蔽剂氰化钠改为三乙醇胺,同时指示剂换成钙紫红素更易保存,显色明显。优化后方法更易操作,试剂更易获得且毒性小,指示剂显色明显,更易保存。可运用于钙含量较高(百分数级)产品钙含量测定。 相似文献
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酸性条件下利用亚硝酸盐具有氧化性的特性氧化KI 生成I2,I2 和淀粉作用灵敏地生成I2- 淀粉蓝色络合物的特效反应,建立光度法测定食品中亚硝酸盐含量的新分析方法。研究表明,I2- 淀粉蓝色络合物最大吸收波长为540nm,在试液pH5、50ml 试液中加入1.0 × 10-2g/ml KI 10ml、0.3% 的淀粉4ml、反应时间6min 的最佳实验条件下,新建方法线性范围为8.0 × 10-4~7.0 × 10-6g/ml,检出限5.0 × 10-8g/ml,相对标准偏差0.7%。新方法具有选择性高、简单、准确和灵敏的优点。 相似文献
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层析-高效液相色谱法测定保健食品中葛根素的含量 总被引:1,自引:0,他引:1
目的 建立测定保健食品中葛根素含量的层析反相高效液相色谱法.方法 D101大孔树脂层析柱(10cm×15cm×1.0 cm)层析,采用ODS C18(250 mm×4.6 mm,5 μm)色谱柱,甲醇 36%乙酸 水=25 3 72作为流动相,检测波长247 nm.结果 葛根素在5.0~50.0μg/ml内呈线性关系,r=O.999 8,方法的回收率为81.6%-100.2%,试样测定RSD为0.84%~1.08%.结论 该方法简便、准确、灵敏,回收率高,分离效果好. 相似文献
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建立以离子液体溴化十四烷基咪唑盐(C14 minBr)作为新型光度增敏剂测定食品中铝(Ⅲ)含量的方法。在pH值为4.8的Britton-Robinson缓冲液中,离子液体C14 minBr对Al3+-铬天青体系具有增敏作用,形成Al(Ⅲ)-CAS-C14minBr三元配合物,并在621nm波长处有最大吸收,铝的质量浓度在0.001~0.150μg/mL范围内符合朗伯比尔定律,表观摩尔吸光系数ε621=1.942×105L/(mol·cm)。将该法用于粉丝与粉皮中微量铝的测定,结果与火焰原子吸收光度法测定结果一致,回收率在97.8%~101.8%之间。 相似文献
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建立了食用油脂、油炸食品、干鱼制品、饼干、方便面、速煮米、干果罐头、腌制肉制品等含油食品中抗氧化剂叔丁基对苯二酚(TBHQ)的气相色谱分析方法。样品经粉碎或混匀以石油醚提取油脂后,用甲醇为提取溶剂,漩涡振荡提取充分后取清液经气相色谱分离后用氢火焰离子化检测器检测,根据样品峰面积与标准峰面积比较定量。该方法对TBHQ的检出限为0.002g/kg,相关线性系数r=0.9999,线性范围为0.1mg/mL~2.5mg/mL;相对标准偏差为0.04%。 相似文献