Detection of the hepatotoxic microcystins in 36 kinds of cyanobacteria Spirulina food products in China

Gel filtration chromatography, ultra-filtration, and solid-phase extraction silica gel clean-up were evaluated for their ability to remove microcystins selectively from extracts of cyanobacteria Spirulina samples after using the reversed-phase octadecylsilyl ODS cartridge for subsequent analysis by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The reversed-phase ODS cartridge/silica gel combination were effective and the optimal wash and elution conditions were: H₂O (wash), 20% methanol in water (wash), and 90% methanol in water (elution) for the reversed-phase ODS cartridge, followed by 80% methanol in water elution in the silica gel cartridge. The presence of microcystins in 36 kinds of cyanobacteria Spirulina health food samples obtained from various retail outlets in China were detected by LC-MS/MS, and 34 samples (94%) contained microcystins ranging from 2 to 163 ng g^?1 (mean?=?14?±?27 ng g^?1), which were significantly lower than microcystins present in blue green alga products previously reported. MC-RR?–?which contains two molecules of arginine (R)?–?(in 94.4% samples) was the predominant microcystin, followed by MC-LR?–?where L is leucine?–?(30.6%) and MC-YR?–?where Y is tyrose?–?(27.8%). The possible potential health risks from chronic exposure to microcystins from contaminated cyanobacteria Spirulina health food should not be ignored, even if the toxin concentrations were low. The method presented herein is proposed to detect microcystins present in commercial cyanobacteria Spirulina samples.     

童叟皆欺 明码“伤”标

<正> 道高一尺,魔高一丈,打假的招多,造假的招也不少。“假作真时真亦假”,有时,个别黑心的小贩,把真牌子往假货那一戳,真能把老实巴交的消费者气个半死。 有位吕先生在家门口的小店买苹果时,老板向他推荐一种有商标的苹果。可回家一洗,吕先生却发现受骗了,原     

高效液相色谱法检测乳品中3种甜味剂

建立了乳制品中安赛蜜、阿斯巴甜和纽甜的高效液相色谱分析方法。样品用沉淀剂沉淀过滤后,以乙腈-磷酸二氢钠溶液为流动相,C18反相色谱柱分离,紫外检测器210nm检测。结果表明:3种甜味剂可在25min之内实现完全分离。安赛蜜和阿斯巴甜在1~100mg/kg,纽甜在0.5~100mg/kg范围内呈良好的线性关系,回收率为84.3%~102.6%。该方法用于乳制品中3种甜味剂的测定,灵敏度高,定量准确,节省时间和成本。     

试纸法对肉类熟食制品中亚硝酸盐的快速检测

采用国家标准方法(GB5009，32-85)“盐酸萘乙二胺法测定肉制品中亚硝酸盐含量”，利用亚硝酸盐在酸性条件下与对氨基苯磺酸重氮化反应的化合物与盐酸萘乙二胺偶合成红紫色化合物，颜色的深浅与亚硝酸盐的含量成正比的原理，建立制备快速测定亚硝酸盐的新方法一试纸法。试纸法作为一种快速的现场检测方法，其特点是操作简单、携带方便、价格便宜、检测快捷，并具有一定的选择性、准确性和灵敏度。对指导生产及市场流通质量控制，保障食品安全具有一定的实际意义。     

Detection of genetically modified organisms in processed meat products on the Serbian food market

The addition of soybean proteins to processed meat products has significantly increased in recent years due to the interesting functional and nutritional properties of these vegetable proteins. Since the Roundup Ready (RR) soybean is the only transgenic soybean line approved for market in EU this work was aimed at monitoring its presence in meat products on the Serbian food market. The extracted DNA was analyzed using duplex polymerase chain reaction (PCR) with primer pairs aimed at the lectin gene and 35S promoter. Samples positive for the presence of GM soybean were subjected to a real-time quantification of the percentage of RR soya. The results indicated that out of fifty processed meat products examined, twelve gave positive results with 35S promoter and all contained RR soya below 0.1%.     

Detection of melamine and cyanuric acid in vegetable protein products used in food production

The multitude of food recalls in 2007 clearly demonstrated that total nitrogen-content (ΣN) determination by means of near-infrared spectroscopy (NIRS) and Kjeldahl-based measurements can be deceived, and should no longer be regarded as a complete quality assurance program for nutritive-protein evaluations. Furthermore, contemporary Canadian-employed analytical tools are precariously limited in their ability to effectively assure a product where there is no a priori knowledge of the environmental toxin(s) involved. In light of these challenges, this study explored a number of analytical techniques used to assess and furthermore assure the quality of vegetable protein products (VPPs). Using liquid chromatography with tandem mass spectrometry (LC/MS/MS) technologies, a combination of VPP-based samples was analyzed for the presence of nitrogen-bearing environmental toxicants. Of the 52 samples tested, involving an assortment of matrices, melamine and cyanuric acid were positively identified (>1 ng/mL) in 22 and 17 samples, respectively. Subsequent high pressure liquid chromatography with ultraviolet/visible (HPLC-UV) amino acid profiling further confirmed the adulteration of those materials contaminated with melamine and melamine-related compounds. Based on the evidence presented herein, LC/MS/MS in combination with HPLC-UV provides for a reliable food safety detection system as applied to VPPs. Moreover, HPLC-UV is indispensable as a stand-alone 1st level of screening to assess the integrity of a VPP or any nutritive protein-based sample.     

Detection and serological screening of conditionally-pathogenic enterobacteria isolated from food products and the environment

The spread of some coliform bacteria in foods, the faeces of children and adults and in human environment was studied, and the evaluation of their toxigenic potential and serological properties was given. More then 160 strains of enterobacteria including 70 strains of Escherichia spp were described. The frequency of detection enterotoxigenic E. coli in foods--18%--was approximately similar an amount of ETEC strains which was isolated in humans (22%). 3 strains of E. coli) 157 were found in foods and in clinical samples (1.9%). The observed results have confirmed the proposal about the increasing of ETEC E. coli food-borne transmitting and dissemination its in the environment.     

几种亟待开发的食品包装机械

随着包装食品内需扩大以及出口需求的增加,市场上有几种需求旺盛的食品包装机械亟待开发。 一、啤酒与饮料罐装成套设备 目前,全国的主要啤酒厂有近千家,饮料厂2000余家。专家认为,啤酒罐装机械成套设备应重点开发年产5万吨的中型设备和适度发展年产10万吨以上的大型设备,而高速、     

Detection of nanomaterials in food and consumer products: bridging the gap from legislation to enforcement

This paper describes the requirements and resulting challenges for the implementation of current and upcoming European Union legislation referring to the use of nanomaterials in food, cosmetics and other consumer products. The European Commission has recently adopted a recommendation for the definition of nanomaterials. There is now an urgent need for appropriate and fit-for-purpose analytical methods in order to identify nanomaterials properly according to this definition and to assess whether or not a product contains nanomaterials. Considering the lack of such methods to date, this paper elaborates on the challenges of the legislative framework and the type of methods needed, not only to facilitate implementation of labelling requirements, but also to ensure the safety of products coming to the market. Considering the many challenges in the analytical process itself, such as interaction of nanoparticles with matrix constituents, potential agglomeration and aggregation due to matrix environment, broad variety of matrices, etc., there is a need for integrated analytical approaches, not only for sample preparation (e.g. separation from matrix), but also for the actual characterisation. Furthermore, there is an urgent need for quality assurance tools such as validated methods and (certified) reference materials, including materials containing nanoparticles in a realistic matrix (food products, cosmetics, etc.).     

Detection of nanomaterials in food and consumer products: bridging the gap from legislation to enforcement

This paper describes the requirements and resulting challenges for the implementation of current and upcoming European Union legislation referring to the use of nanomaterials in food, cosmetics and other consumer products. The European Commission has recently adopted a recommendation for the definition of nanomaterials. There is now an urgent need for appropriate and fit-for-purpose analytical methods in order to identify nanomaterials properly according to this definition and to assess whether or not a product contains nanomaterials. Considering the lack of such methods to date, this paper elaborates on the challenges of the legislative framework and the type of methods needed, not only to facilitate implementation of labelling requirements, but also to ensure the safety of products coming to the market. Considering the many challenges in the analytical process itself, such as interaction of nanoparticles with matrix constituents, potential agglomeration and aggregation due to matrix environment, broad variety of matrices, etc., there is a need for integrated analytical approaches, not only for sample preparation (e.g. separation from matrix), but also for the actual characterisation. Furthermore, there is an urgent need for quality assurance tools such as validated methods and (certified) reference materials, including materials containing nanoparticles in a realistic matrix (food products, cosmetics, etc.).     

豆制品行业现状受其安全问题的思考

从计划经济时代到市场经济时代,我国豆制品行业不断发展。近几年,豆制品行业出现了一个爆发性的增长,企业的规模、产量、产值、销售额都在大幅度稳步提升。据国家质量监督检疫总局网上数据显示,截止到2010年,我国已经获得食品质量安全市场准入的豆制品企业达到3751家,与2009年初统计的1800多家家相比,增幅达50％以上。这样的增长速度在食品行业内是比较快的,对拉动国内消费也起到了极大作用。当然,在高速发展的同时,豆制品行业也面临着一些问题。     

Claiming health in food products

Health-related information is increasingly used on food products to convey their benefits. Health claims as a subcategory of these messages link the beneficial component, functions or health outcomes with specific products. For consumers, health claims seem to carry the message of increased healthiness, but not necessarily making the product more appealing. The wording of the claim seems to have little impact on claim perception, yet the health image of carrier products is important. From consumer-related factors the relevance and attitudes towards functional foods play a role, whereas socio-demographic factors have only minor impact and the impact seems to be case-dependent. Familiarity with claims and functional foods increase perceived healthiness and acceptance of these products. Apparently consumers make rather rational interpretations of claims and their benefits when forced to assess the information, but we still know relatively little about consumer understanding of the message content in claims and even less about the assessment of personal relevance of the claimed benefits. In future studies more emphasis should be put on including contextual influences and realistic conditions in assessing consumer understanding and use of health claims in purchase decisions.     

Sugar crystallization in food products

A review of the recent literature on crystallization of the commercial sugars (fructose, glucose, lactose, and sucrose) is presented. Topics include: NUCLEATION--The formation of the crystalline phase from supersaturated solutions can occur by either a spontaneous or a forced nucleation mechanism. Recent work on the mechanisms, kinetics, and impact of both heterogeneous and secondary (contact) nucleation is discussed. GROWTH--Recent studies on the mechanisms and kinetics of crystal growth will be reviewed. This discussion includes work on the growth rate dispersion exhibited by these sugars. EFFECTS OF IMPURITIES AND ADDITIVES--The presence of impurities and additives (including mixed sugar systems) affects both the nucleation and growth steps. A discussion of the recent work in this area is included. Emphasis is placed on the relationship between these crystallization phenomena and the solution structure for comparison purposes.