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HPLC同时检测葡萄酒中10种单体酚的方法 总被引:1,自引:0,他引:1
本研究建立了用HPLC同时测定葡萄酒中没食子酸、( )-儿茶素等10种单体酚的方法.色谱条件为:Hibar RT Lichrospher反相C18柱,流动相A为水:乙酸(98:2),流动相B为乙腈,梯度洗脱,流速为1.0ml/min,检测波长为280nm.在该色谱条件下各个单体酚在30min内得到了良好的分离,各物质的含量与峰面积呈良好的线性关系,且回收率较高,重复性好,且具有定量准确、快速等特点.结果表明,三种葡萄酒均被检测到了这10种单体酚,且它们在红葡萄酒中的含量显著高于白葡萄酒. 相似文献
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《食品工业》2016,(4)
试验建立了一种用HPLC测定葡萄酒中没食子酸、原儿茶酸等12种单体酚的方法。采用C18色谱柱,乙腈-冰醋酸-水溶液为流动相,梯度洗脱,流速为1.0 mL/min,柱温30℃,检测波长280 nm。检测结果表明,在该色谱条件下各单体酚在40 min内能得到较好分离,各物质的含量与峰面积间呈良好的线性关系,方法的检出限在0.028~0.216之间,回收率均在85%以上,且相对标准偏差均小于4%,重复性好。采用该种方法测定6种相同地区、不同年份、不同品种葡萄酒中单体酚的含量。结果表明,不同年份、相同品种葡萄酒中12种单体酚含量各不相同,没食子酸、儿茶素含量均较高;葡萄酒中除个别酚酸含量有所增加以外,大部分单体酚含量均随储藏时间的增长而有所降低。 相似文献
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建立了一种测定葡萄酒中7种单体酚含量的超高效液相色谱(UPLC)检测方法。采用ACQUITY BEH C18色谱柱,以甲醇/乙酸铵-乙酸缓冲溶液为流动相,0.2 mL/min梯度洗脱,变波长检测,各化合物线性关系较好(R2>0.993),不同的添加水平的回收率在84.0%~108.4%范围,方法重复性较好(RSD≤6.08%)。该文利用UPLC法分析了不同地区、不同年份的葡萄酒中7种单体酚的含量,结果表明,葡萄酒中含有丰富的单体酚,单体酚的含量因酒样含糖量、品牌、厂家和原料产地不同而差别很大。 相似文献
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建立分散液-液微萃取与高效液相色谱联用技术测定石斛酚的分析方法。通过对实验条件的筛选及优化,得到最佳条件:pH 3,辅以涡旋方式进行萃取,萃取溶剂为120 μL正戊酸、萃取时间1 min,分散剂为曲拉通X-114、用量80 μL。此方法进行萃取,检出限为2.625 μg/L,定量限为8.74 μg/L,线性范围为0.10~30.00 mg/L,萃取富集倍数平均值为28.02,萃取回收率平均值为1.01。将建立的分析方法应用于实际石斛样品的测定,结果表明该方法能对石斛中的石斛酚进行高效萃取与富集,方法快速简便。 相似文献
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本文报道了以大豆粉为材料,通过多个实验室合作定值的方法,测试数据采用GB6379—86方法,通过实验室试验,确定标准测试方法的再现性作统计检验。在99%的置信限下,剔除高度异常值后,计算出加权平均值,作为参比物质的保证值的研究方法。研制出了两个大豆粉氨基酸标准物质。并已得到应用。 相似文献
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食品检验是了解食品质量安全状况、収现风险隐患的直接有效的措施,也是我国食品安全监管工作的重要环节。作为食品检验的重要组成部分,样品管理直接兲乎到检测数据的公正性、科学性、准确性,对提高检测机构的权威性也具有重要意义。相兲人员大多对抽样的觃范性和科学性、检验技术的兇迚性和准确性非常兲注,对样品管理的重视程度相对不足。然而,由于各种因素的影响,食品检验中样品管理还存在诸多需要注意的问题,可能影响食品检验的准确性和有效性。本文对对样品接收、样品保存、样品制备等环节实施严栺管理迚行总结分析,以期降低检验风险。 相似文献
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Composite milk samples, in which milk from all 4 bovine quarters is collected in a single vial, are widely used in many developed dairy industries for detection of intramammary infections (IMI). These samples are more economical for use in culturing protocols than individual quarter samples, and may be useful when considering management options at the cow and herd level. The dilution effect may be problematic, however, resulting in lower sensitivity (Se) in IMI detection on composite samples. Relative Se and specificity (Sp) in composite samples have previously been described for some major pathogens, but because the causative organism for IMI is initially unknown, it is beneficial to investigate the reliability of composite samples for detection of all types of mastitis-causing bacteria. The Canadian Bovine Mastitis Research Network has a large data collection platform—the National Cohort of Dairy Farms—containing a vast amount of data on mastitis in Canada. These data have been used to further investigate the Se and Sp of composite samples in detecting IMI caused by specific mastitis pathogens. Milk samplings of selected cows before dry-off, after calving, and during lactation (n = 48,835 samples) were employed to this end. Composite samples showed moderately high Se for Staphylococcus aureus (77.1%, 95% CI = 73.3-80.5) and Streptococcus dysgalactiae (73.4%, 95% CI = 60.9-83.7), with moderate Se for Streptococcus uberis (62.1%, 95% CI = 49.3-73.8) and coagulase-negative staphylococci (59.8%, 95% CI = 58.4-61.2). Sensitivities always increased as the number of affected quarters increased. Composite samples also showed high Sp (>97%) for most organisms. Factors such as lactation number and stage of lactation were evaluated for their influence on the Se and Sp of composite sampling, but were only found to be significant for coagulase-negative staphylococci. Predictive values using the herd prevalences found across Canada were calculated and can be useful in field scenarios when composite sampling is employed to assist mastitis management. When used to detect newly occurring IMI in pairs of samples taken before dry-off, post-calving, and also prior to and subsequent to the dry period, composite samples were shown to have lower Se but similar Sp for all pathogens investigated. Composite samples can be used to detect IMI and new IMI in dairy cows, but the Se and Sp of the procedure should be taken into account. 相似文献
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纺织品色样审单要求有物理指标、品种规格、色泽要求和特殊要求。确认色样时,应先用灰卡对色,然后进行小样对色,再进行大样的确认。在生产中,对出现的“跳灯”、同色异谱现象,提出了相应的解决措施。 相似文献
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根据筒子纱活性染料染色大小样的差别及特点,分析了造成染色一次性符样率低的相关因素,拟定了大生产与小样仿色操作要点及规则,设计了三条适合不同染料染色的工艺曲线,并运用于大生产。 相似文献
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提高散棉染色大小样重现性的实践 总被引:1,自引:0,他引:1
介绍了影响棉花散纤维染色大小样重现性的各种因素及提高散棉染色一次命中率的有效途径和相应措施,指出应从材料、设备、工艺等方面着手,加强对大小样试验规律的摸索,提高染色员工的技能,实现散棉染色的大小样重现性。 相似文献
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Aflatoxins can cause damage to the health of humans and animals. Several institutions around the world have established regulations to limit the levels of aflatoxins in food, and numerous analytical methods have been extensively developed for aflatoxin determination. This review covers the currently used analytical methods for the determination of aflatoxins in different food matrices, which includes sampling and sample preparation, sample pretreatment methods including extraction methods and purification methods of aflatoxin extracts, separation and determination methods. Validation for analysis of aflatoxins and safety considerations and precautions when doing the experiments are also discussed. 相似文献