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HPLC测定啤酒和麦汁中的糖类化合物 总被引:1,自引:0,他引:1
HPLC测定啤酒和麦汁中的糖类化合物魏玲(北京双合盛五星啤酒集团公司啤酒研究检测中心)糖类的分析测定在啤酒生产过程中具有重要意义。糖类测定方法很多,一般的化学分析方法,如比色法、滴定法、旋光法、比重法等只能测定总糖和还原糖。近十多年来随高效液相色谱法... 相似文献
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建立了体积排阻色谱法检测牛奶、乳粉、乳清粉中α-乳白蛋白含量的分析方法。使样品中的α-乳白蛋白经过盐酸胍变性以及2-巯基乙醇还原后,形成展开的α-乳白蛋白的单体结构,调节p H至6.5~7.5,串联使用两根体积排阻色谱柱MAb Pac SEC-1 300A(7.8mm×300 mm),盐酸胍为流动相,等梯度洗脱,用光电二极管阵列检测器在280 nm进行检测。本方法可以同时适用于牛奶、乳粉以及乳清粉中α-乳白蛋白的分离分析。α-乳白蛋白的线性范围为10~500 mg/L,线性相关系数均大于0.99。α-乳白蛋白的检出浓度为3.00μg/m L (S/N=3),定量浓度为10.0 g/m L(S/N=10)。牛奶、乳粉-乳白蛋白含量的分析方法。样1品中的α-乳白蛋白经过盐酸胍变性以及2-巯基乙醇还原后,形成展开的α-乳白蛋白的单体结构,调节p H至6.5~7.5,串联使用两根体积排阻色谱柱MAb Pac SEC-1 300A(7.8 mm×300 mm),盐酸胍为流动相,等梯度洗脱,用光电二极管阵列检测器在280 nm进行检测。本方法可以同时适用于牛奶、乳粉以及乳清粉中α-乳白蛋白的分离分... 相似文献
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高效体积排阻色谱测定油脂中氧化甘油三酯聚合物 总被引:8,自引:1,他引:8
为了分析甘油三酯氧化产物——氧化甘油三酯及其聚合物的组分分布,研究了高效体积排阻色谱检测高相对分子质量聚合物的方法,建立了采用正相硅胶制备色谱预分离油脂中极性组分,极性组分以高效体积排阻色谱-示差折光检测器测定,标准相对分子质量聚苯乙烯定性,峰面积归一化法定量的检测方法.油脂中极性组分的典型色谱峰构成是:氧化甘油三酯寡聚合体、氧化甘油三酯二聚体、氧化甘油三酯单体、甘油二酯、游离脂肪酸等.以氧化甘油三酯聚合物鉴别地沟油等深度氧化劣变食用油具有良好的应用前景. 相似文献
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啤酒发酵过程中风味物质的形成和变化 总被引:1,自引:0,他引:1
本文通过对实验的四种不同品种的啤酒在发酵过程中的GC检测追踪,来反映各种风味物质在发酵过程中的形成和变化,以及不同品种风味物质含量形成的差异。 相似文献
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气相色谱法测定啤酒中的联二酮 总被引:5,自引:0,他引:5
本文介绍了采用GC-ECD分别测定啤酒中双乙酰和2,3-戊二酮的方法,文中讨论了样品制备及GC的测定条件。采用本法测定双乙酰的变异系数为2.4~5.3%,2,3-戊二酮为2.8~4.5%,添加联二酮标样的回收率良好。分别采用气相色谱法和比色法测定了25种不同啤酒样品中的联二酮含量,结果表明GC法明显优于比色法,GC法更适合作为质量控制分析用。 相似文献
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介绍了毛细管气相色谱法分析啤酒中风味物质的方法。进样器为HS40XL;主机为 ASXL;色谱柱为 PE-5(60m×0.53mm×1.5μm);载气为高纯氮;检测器为 FID。比较了外标法和内标法两种定量方法,是用 F 检验法对两种方法进行了对比,两种定量方法差异不大。为了方便检测,我们采用外标法定量。 相似文献
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采用反吹技术改进了气相色谱检测啤酒中乙醛、高级醇、高级酯等10种主要风味物质的方法。用配备毛细管色谱柱、氢火焰离子化检测器及微板流控装置的气相色谱仪,对啤酒直接进样,建立了一种快速分析的气相色谱分析方法。结果表明,采用内标法定量,啤酒中10种主要的风味物质具有良好的线性关系(R2>0.999)。对同一啤酒五次进样,测得的相对标准偏差为0.13%~2.77%。对啤酒加标回收,回收率达到96%~104%。采用反吹技术可以省去复杂的样品前处理,有效降低样品基质的影响,缩短样品的分析时间,提高效率,减少材料消耗。该方法以期能快速检测生产过程中啤酒的风味物质含量,有针对性控制啤酒的生产工艺,提高啤酒的质量。 相似文献
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反相流动注射法是一种快速、简便、精确,自动化操作的方法。在碱性(pH12的Na2B4O7-NaOH缓冲溶液)条件下,单宁能还原磷钨酸生成蓝色化合物在700nm有最大吸收峰。在最优的试验条件下,单宁浓度为0~10.0mg/L范围内峰高与浓度成线性关系,其线性相关系数为0.9996,方法检出限DL=16.8μg/L,精密度RSD=0.66%(n=12)。应用于实际啤酒样品中单宁的检测,加标回收率在99.25%-100.07%之间,具有较好的重现性和准确性;与标准分析方法比较,测定结果令人满意。 相似文献
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Fish and fish products (14 samples), Indian foods and meals (10 samples), spices (30 samples) and beers (10 samples) were analysed for their phytoestrogen content, and a number of significant non-soya sources of dietary phytoestrogens were identified. No isoflavones were detected in unprocessed, farmed or ocean fish, but some samples of processed fish products contained soya isoflavones, which are assumed to come from coatings or protein addition. Additionally, some processed fish products contained, genistein glycocongugates not derived from soya. Genistein was detected in Indian meals such that, for example, a single portion of a vindalooo curry contained 11 mg genistein. The origin was most likely from the spices used, since the analysis of curry powders, chilli powder, crushed red chillies, garam masala and tandoori powder revealed that some contained genistein at more than 100 mg kg-1. Cumin was the most likely source material, although not all individual samples of cumin tested contained high levels of genistein. Prenylnaringenin phytoestrogens were determined in UK hop-based beers at mean concentrations of 0.21 mg-1 6-prenylnaringenin and 0.06 mg-1 8-prenylnaringenin. The beers also contained traces of daidzein, genistein and biochanin A. The significance of 'hidden soya' in processed foods and these non-soya sources of phytoestrogens is that UK dietary intake of phytoestrogens must be assumed to be higher than estimated previously and that some sources of phytoestrogens remain poorly characterized. 相似文献
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韩曦莹 《食品安全质量检测学报》2020,11(10):3301-3305
目的建立气相色谱法测定陈皮中丙溴磷残留量的分析方法。方法样品经乙腈提取,经过滤,QuECHERS净化,浓缩后,用丙酮定容,采用气相色谱法测定、外标法定量。结果丙溴磷在0.005~1.000μg/mL范围内线性良好,相关系数r~2达到0.999;方法检出限为0.008 mg/kg;平均回收率为89.9%~110.8%,相对标准偏差(relative standard deviation,RSD)为2.2%~3.3%(n=6)。结论本方法操作简便、灵敏度高、准确度好,适用于陈皮中丙溴磷残留量测定。 相似文献
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Kunbo Wang Fang Liu Zhonghua Liu Jianan Huang Zhongxi Xu Yinhua Li Jinhua Chen Yushun Gong Xinghe Yang 《International Journal of Food Science & Technology》2011,46(7):1406-1412
As tea is one of the most popular beverages consumed worldwide, it is important for customers and business investigators to develop an easy and reliable method to discriminate between different types of teas from each other. A total of eighty‐seven types of various white, green, oolong, black and Puer teas were collected from the major tea estates in China, and their catechin contents and volatile compounds were compared by high performance liquid chromatograph and gas chromatograph mass spectrometer. It was found green tea contained the highest concentrations of total catechins, (?)‐epicatechin gallate (ECG) and (?)‐epigallocatechin gallate (EGCG), while oolong teas contained the highest concentrations of (?)‐epigallocatechin (EGC) among these five types of teas. The aroma composition and their quantities in different types of teas varied quite widely. The concentration of ECG, EGCG, pentanal, hexanal, methyl jasmonate, indole, (E,E)‐2,4‐hexadienal and 1,2,3‐trimethoxybenzene was shown to be different and could be used to discriminate white, green, oolong, black and Puer teas. The result showed that different types of teas could be partially classified by cluster analysis using index of individual catechins and volatile components. 相似文献
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目的建立气相色谱-质谱法(gas chromatography-mass spectrometry,GC-MS)测定啤酒和腊肠中N,N-二甲基亚硝胺的方法。方法试样经二氯甲烷超声提取、离心,SILICA/PSA玻璃柱净化后气相色谱/质谱仪直接测定,D6-N,N-二甲基亚硝胺内标法定量。结果加标回收率范围为66.9%~103.4%,相对标准偏差(RSD)在2.5%~7.7%。将该方法用于实际样品分析,30份啤酒中均未检出N,N-二甲基亚硝胺,8份腊肠样品中检出2份阳性样品,含量均低于肉制品中N,N-二甲基亚硝胺限量值3.0μg/kg。结论此方法简便快速,灵敏度较高,可以用于啤酒和腊肠中N,N-二甲基亚硝胺的准确定量。 相似文献
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Pawel Pohl 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(6):693-703
Major, minor and trace metals are important in beer fermentation since they supply the appropriate environment for yeast growth and influence yeast metabolism. A real concern is the content of copper (Cu) and iron (Fe), which are involved in beer conditioning and ageing through reactions resulting in formation of reactive oxygen species. The reactive oxygen species readily oxidize organic compounds present in beer, changing the quality of foaming and the flavour stability of beer. In view of brewing technology and beer processing, knowledge regarding functions of metals and their speciation in brewing liquors and beer is of special significance. Metals in beer also have a certain nutritional importance, but their actual effect related to beer consumption depends on the type of species they form with low and high molecular mass organic ligands which naturally occur in beer. This review covers the determination and fractionation of metals in beer using atomic spectrometry methods. Special attention is drawn to the role of metals in beer and brewing, possible metal associations, methods of beer preparation before analysis on the total metal content, and approaches to metal partitioning in beer. 相似文献