气相色谱法对不同食品中甜蜜素测定的改进

对气相色谱法测定食品中甜蜜素含量的方法进行优化和改进。结果表明:以蛋白沉淀法作为半固体和固体样品预处理的回收率最好,在优化的色谱条件下,甜蜜素和内标物分离度高,测定甜蜜素含量以乙酸丁酯为内标来定量,线性范围为0.1 g/L～1.0 g/L,相关系数为0.999 6,检出限为0.01 g/kg,精密度<5%,回收率为85%～98%。     

毛细管柱气相色谱法测定乳制品中的甜蜜素

采用Rtx-1非极性毛细管柱对乳制品中的甜蜜素的检测方法进行了探讨,改进了样品处理方法,建立了应用Carrez试剂沉淀蛋白,毛细管柱分离检测乳制品中甜蜜素的方法.经方法验证,方法检出限为5.16μg,定量下限为15.48μf,在0.0～1.0μg浓度范围内线性关系良好,相关系数R2为0.9999,回收率在94.2%～1...     

毛细管气相色谱法测定冷饮中甜蜜素分析误差预测

目的探讨毛细管气相色谱法测定冷饮中甜蜜素含量的适宜条件并对方法的误差进行预测。方法样品经国标方法提取,毛细管柱OV-1程序升温条件下分离,火焰离子化检测器(FID)检测;采用精密度-偏性分析质量控制程序进行误差预测。结果方法的线性范围为10～1 000μg/ml,线性相关系数(r)为0.999 5,方法检出限为3.0μg;除冷饮样品外,其余试样批内、批间变异分析F相似文献   

气相色谱内标法测定蜜饯中的甜蜜素含量

建立气相色谱内标法测定蜜饯中甜蜜素含量的方法。蜜饯中的甜蜜素经水超声提取后,以乙酸丁酯为内标物,采用HP-5毛细管柱,程序升温:初温60℃保持6 min,以40℃/min升温至200℃保持3 min,进样口温度230℃,氢火焰离子化检测器(flame ionization detector,FID)260℃进行检测。当样品的称样量为5 g时,蜜饯类食品中的甜蜜素的检出限为0.008 g/kg,方法的标准曲线线性良好,相关系数为0. 999 0,平均回收率在88.46%～104.26%之间,相对标准偏差为3.97%。     

调味面制品中甜蜜素的测定

目的 测定调味面制品中的环己基氨基磺酸钠(甜蜜素)。方法 采用毛细管气相色谱法(氢火焰离子化检测器FID)测定食品添加剂甜蜜素在调味面制品中的残留量。结果 该法定量线性关系良好, 回归方程为: Y=0.489876X?1.12084(r =0.99976), 最低检测限为: 0.002 g/kg, 加标回收率为85.2%~105.3%。结论 该方法灵敏度高、操作方便、准确、稳定性好, 适合调味面制品中甜蜜素的测定。     

毛细管柱气相色谱法测定食品中微量甜蜜素

研究了测定食品中微量甜蜜素的毛细管柱气相色谱ECD分析方法。结果显示，该法的线性范围是0．01～10．0μg／mL，最低检出限为0.05μg／g，回收率为93.0％～104．0％。     

气相色谱法测定槟榔中甜蜜素含量的不确定度评定

目的评定气相色谱法测定食用槟榔中环己基氨基磺酸钠(又名甜蜜素)的不确定度评定方法。方法根据气相色谱法定量测定食用槟榔中甜蜜素含量的测定原理,较全面的考虑整个测定过程的不确定度来源,建立结果不确定度评定的数学模型,并探讨其测定结果不确定度。结果在95%的置信区间下,当槟榔中甜蜜素含量为6.19 g/kg时,其扩展不确定度为0.18 g/kg, k=2。结论槟榔中甜蜜素的检测不确定度主要来源为标准曲线的拟合。     

用毛细管气相色谱分析黄酒中的甜蜜素

建立了毛细管气相色谱分析黄酒中的甜蜜素的方法。先使样品通过沸水浴蒸发干后,在硫酸介质中与亚硝酸钠反应,生成环己醇亚硝酸酯,最后用毛细管柱分离,GC-FID检测甜蜜素含量。结果表明,本方法线性范围为0.1～2.0 mg/mL,最低检出限为2 mg/kg,加标回收率为95.4%～113.7%,相对标准偏差为2.34%～4.84%。该方法操作简便、快速、精密度好、准确度高,比较适合用于黄酒中甜蜜素含量的测定。     

顶空-气相色谱法快速测定饮用酒类中甜蜜素含量

该实验建立了顶空-气相色谱（HS-GC）快速检测饮用酒类中甜蜜素的方法。样品经加热去除大部分乙醇和挥发性物质,样品提取液经衍生后,用顶空-气相色谱仪分析,以甜蜜素衍生产物环己烯为目标物,外标法定量。结果表明,当甜蜜素在饮用酒类中对应含量为1～100 mg/kg时线性关系良好（R2=0.998 9）,检出限和定量限分别为0.1 mg/kg和0.3 mg/kg,加标回收率为94.3%～107.1%,相对标准偏差（RSD）为2.5%～7.1%(n=6),精密度试验结果RSD为3.1%～4.9%。该方法简单、高效、环境友好、可靠、准确,可用于各种饮用酒类中甜蜜素的快速定量检测。     

气相色谱法测定蜜饯中甜蜜素含量的不确定度评定

目的评定气相色谱法测定蜜饯中甜蜜素含量的不确定度。方法通过建立不确定度数学模型,根据GB 5009.97-2016《食品中环己基氨基磺酸钠的测定》气相色谱法测定蜜饯中甜蜜素含量,分析该方法测量不确定度的主要来源,幵评定了各标准不确定度的分量。结果在蜜饯中的甜蜜素含量测定中,当样品的甜蜜素含量为8.91 g/kg,其扩展不确定度为0.631 g/kg (k=2),结果表示为(8.9±0.6) g/kg。结论本研究掌握了引入不确定度的因素,通过降低可控不确定度来提高测量的准确度,该质量控制手段可用于合理的体现测定结果的可靠程度。     

Review of techniques to manufacture micro-hydrogel particles for the food industry and their applications

Microgels are ‘soft’ microscopic cross-linked polymeric particles that are being increasingly exploited in a variety of industries for rheology control, encapsulation and targeted delivery. They are valued because of the ability to tune their functionality to address specific applications in oil recovery, coatings, drug delivery, cosmetics, personal care and foods. Food microgels are typically biopolymer hydrogels in the form of microspheres, nanospheres (also called nanogels), spheroids and fibres. The utilisation of engineered microgels in foods has so far been limited, despite their great potential to address several needs in the food industry, including: satiety control, encapsulation of phytonutrients and prebiotics, texture control for healthier food formulations (e.g. reduced fat products), and targeting delivery to specific areas in the digestive tract. We review the scientific and patent literature on the utilisation and manufacturing methods for producing microgels with an emphasis on micro-hydrogels for food applications.     

12—A CRITIQUE OF SOME HYPOTHESES RELATING TO THE HETEROGENEITY OF THE HIGH-SULPHUR PROTEINS OF WOOL

Joubert and Burns prepared a large number of fractions from the high-sulphur proteins of wool and estimated their molecular weights and amino-acid compositions. Their data have been re-examined in order to look for statistically significant interrelations between amino acids and between the proportion of various amino acids and molecular weight. Statistical analysis of the data is also used to examine the credibility of some hypotheses concerning the mechanism of keratin biosynthesis and to provide further evidence for the existence of families of proteins within the high-sulphur fractions of wool.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the latest scientific     

China textile machinery: taking off in progress

正Among the 1600 exhibitors who take apart in the ITMA ASIA+CITME2014 2/3 are Chinese manufactures.If the numerous figures failed to attract your attention,the increase of quality should draw your focus.To adopt the demand of developing textile machine market,domestic textile machinery enterprises now follow the slogan of"technology drives development"to enhance product competitiveness.Our domestic sellers will showcase product ranging from spinning,weaving,dyeing and printing,     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of     

The Latest Data about Development of Chinese Printing Industry in 2013

In the 2014 China（Shanghai）International Printing Week,Director Wang Yanbin released the latest data about development of Chinese printing industry in 2013.According to statistics,in 2013,the total output value of Chinese printing industry exceeded 1trillion Yuan for the first time,reaching 1.03985 trillion Yuan.There were 105,000 printing enterprises in China,employees were 3.415 million.The total asset was 1.06247 trillion Yuan;     

The State Council Issued "Directory of Government Approved Investment Projects(2013 Edition)"

正On December 2nd,2013,the State Council issued the notification of"Directory of Government Approved Investment Projects(2013 Edition)"(hereafter referred to as"notification").It is pointed out in the"notification"that in order to further deepen reforms in investment systems and administrative examination and approval systems,simplify administrative procedures and delegate powers to lower levels,earnestly     

Top Ten News of China's Paper Industry 2013

On December 24th, 2013, the meeting on the selection of top 10 news of China＇s paper industry 2013 sponsored by 〈China Paper Newsletters〉 was held in Beijing. The yearly selection of the top l0 news, which began in 2000, has become a brand activity widely recognized in the industry thanks to the support from the authorities at all levels and public participation.     

National Development and Reform Commission Issued Announcement for Selection of Major Preliminary Research Projects for the "13~(th) Five-Year Plan"

In Apri Commi major p Plan＂ （h 2014, the National Development and Reform ssion issued an announcement for selection of reliminary research projects for the ＂13th Five-Year ereafter referred to as ＂The Announcement＂）     

Contamination of animal feed and food from animal origin with mineral oil hydrocarbons

Oils and fats used for the production of animal feed can become contaminated with mineral oil material originating from gas oils (C₁₈-C₃₅) or synthetic oils (poly alpha olefins, C₂₅ to beyond C₄₅). An important cause is assumed to be the discharge of waste oils, such as motor oil and hydraulic oils. Mineral oil material was analysed by on-line LC-GC-FID directly in the fat or in a raw extract from animal feed or foodstuffs. In Switzerland in summer/autumn 1999 concentrations in oils and fats for feed production were often found to be between 100 and 1000mg/kg. In the feeds, the average concentration was around 100mg/kg with values ranging up to a maximum of 1000mg/kg; few samples were free of contamination. In animal body fat, the average concentration determined in summer 1999 was 25mg/kg, with a maximum of 150mg/kg, although in samples from December 1999, contamination was substantially lower. In the fat phase of eggs, the average concentration was 30mg/kg, with a maximum of 80mg/kg. Paraffin oil is used for feed production, which may account for part of the contamination problem (e.g. eggs).