食品中脂肪酸的分析方法研究进展

脂肪酸是食品质量控制中的重要指标，快速对其测定对于食品品质鉴定具有重要意义。分析脂肪酸的传统方法如色谱法及色谱质谱联用法的定量准确性较高，但前处理繁琐、费时，消耗大量有机试剂且对样品具有破坏性。近年来，我国对食品安全极为重视，高通量、无损、快速的检测方法在食品检测领域快速发展，因此，有必要对其进行总结综述。快检法如近红外光谱、核磁共振光谱及拉曼光谱与化学计量学、高光谱成像结合被广泛用于脂肪酸快速定量检测及可视化研究。直接质谱分析技术由于具有几乎无需样品前处理的特点，检测脂肪酸时在灵敏度、选择性、高通量及分析速率等方面具备很大优势。该研究介绍了脂肪酸的传统检测方法，并着重综述了光谱分析和直接质谱分析技术在食品脂肪酸检测中的应用进展，进而为食品安全检测、真伪鉴别等提供新思路。     

非靶向筛查技术在农产品质量安全中的最新研究进展

食品安全源头在农产品,农产品质量安全是保障食品安全的重要前提和基础。随着人民生活水平的日益提高,食品安全问题十分突出,存在的污染物种类也十分复杂,因此,为了从源头守护老百姓舌尖上的安全,急需开发简便、快速且高通量检测方法用于农产品中各类风险因子的快速监测。目前,随着质谱精密度和分辨率的不断提高及数据库的扩大和完善,高通量非靶向筛查技术逐渐成为农产品质量安全领域定性筛查和分析的有效技术手段。本文对两种主要的非靶向筛查技术基于飞行时间质谱和静电场轨道肼高分辨质谱进行概述,并简述了两种筛查技术近五年来在农药残留、兽药残留、真菌毒素以及多类污染物筛查和检测中的应用。为了非靶向筛查技术更好的应用于目前的常规检测,未来还需继续努力扩大和完善各类污染物高分辨质谱数据库以及提升农产品中未知物的筛查能力。     

气相色谱-离子迁移谱法检测农产食品中挥发性有机化合物的研究进展

气相色谱-离子迁移谱(gas chromatography -ion mobility spectrometry, GC-IMS)技术结合了气相色谱的高分离能力和离子迁移谱的高灵敏度, 有效地解决了气相色谱低鉴别能力和离子迁移谱对混合物进行检测时存在的交叉灵敏度问题,得到保留时间、漂移时间和信号强度的三维谱图,使定性分析更加准确,并且不需要复杂的样品前处理, 可以直接对样品的挥发性有机化合物(volatile organic compounds, VOCs)进行分析, 极大简化了分析过程,实现快速检测,满足现场分析的需要。作为一项新兴的无损检测技术, GC-IMS技术目前主要应用于食品质量鉴定、掺假溯源分析、食品特征风味分析、新产品开发等方面。本文介绍了GC-IMS技术的基本原理, 重点综述了GC-IMS技术在粮食、果蔬、肉蛋制品等多类食品研究中应用的研究现状, 以期为农产食品的品质分析、风味研究、新食品开发等提供一定的理论指导。     

Nondestructive optical methods of food quality evaluation

Quality control is an important aspect of food production and processing from the point of view of providing foods of acceptable nutritional value, and for providing safety of products. Several characteristics such as size, shape, density, maturity, moisture content, oil content, flavor, firmness, tenderness, color, defects, blemishes, etc., are routinely used in the quality control of agricultural and biological food products. Until recently, most analytical techniques used in quality control required isolation of the food component of interest. The original properties of the product are, therefore, destroyed during sample preparation and analysis. Oftentimes, such analyses are expensive, time consuming, and require sophisticated instrumentation, and hence are not suited for "on-line" quality control of food products. Recent progress in the development of instrumentation utilizing the optical properties of food products has provided several nondestructive techniques for quality evaluation. Most optical methods of nondestructive nature make use of the characteristic absorption spectra of components of interest. Such methods are highly sensitive, rapid, and reproducible, and have been successively used in routine "on-line" quality control of a large number of samples. In this article, theoretical considerations in the development of nondestructive analytical techniques based on the optical properties of several agricultural and biological products are briefly reviewed. A major emphasis is placed on quality control methods that are particularly useful in maturity and/or ripeness evaluation of food products, the detection of external and internal defects, and the subsequent development of automatic sorting machines for on-line measurement of quality.     

Use of ultrasound for characterizing dairy products

It has been known for a long time that acoustic measurements offer some unique features for characterizing liquid food products in their intact state, without any preparation or destruction of the product sample. Acoustic characterization can yield information about fat content, droplet size distribution, and kinetics of product variation with time. Furthermore, acoustic methods are very attractive for on-line process control. This paper addresses several questions: Why does ultrasound attenuate when propagating through a heterogeneous system? What properties of dairy products can be extracted from such ultrasound measurements? Which measurement is better for product characterization: attenuation or sound speed? What measurement precision is required to adequately characterize product properties? What frequency range is of most value for determining these product properties?It is possible to provide answers to many of these questions using experimental data, thereby avoiding, for the moment, any complex mathematical analysis. We present several applications of acoustic spectroscopy for characterizing dairy products, including characterization of the fat content in a wide variety of dairy products; calculation of the fat droplet size distribution in milk without dilution; and calculation of water droplet size in butter, without dilution or melting.     

广式酱油中微生物蛋白组学分析样本的制备

广式酱油发酵周期长、微生物种群多样、代谢物复杂,缺乏微生物蛋白组学分析的样本制备方法。该研究通过比较改良的TCA浓缩法和超滤法两种蛋白纯化方法,利用SDS-PAGE凝胶电泳和LTQ Orbitrap Velos Pro ETD质谱检测酱油微生物宏蛋白组样本制备效果。实验结果表明：TCA浓缩法制备的蛋白样品,其SDS-PAGE凝胶图谱有26个清晰条带,比超滤法多13个;两种法所制备的蛋白经胰蛋白酶酶切后的质谱图可分别鉴定到的2 495和1 682个肽段,说明TCA浓缩法制备的蛋白样品酶切更充分;不同发酵时期（0、60、120 d）的酱油经TCA浓缩法制备的蛋白样品,烷基化、酶切后,通过LTQ Orbitrap Velos Pro ETD质谱检测和Proteome Discoverer 2.5软件分析,可分别鉴定到1 035、1 104、1 046种蛋白质。通过TCA浓缩法制备蛋白组分析样本,操作简便,实验速度快,蛋白质鉴定率高,适用于广式酱油微生物的蛋白质组学的检测分析,为利用蛋白组学分析广式酱油的微生物发酵分子机制打下了一定的基础。     

分光光度法和电感耦合等离子体发射光谱法测定面制品中的铝

目的比较分光光度法和电感耦合等离子体发射光谱法测定面制品中的铝含量。方法以GB5009.182-2017《食品安全国家标准食品中铝的测定》第一法-分光光度法和GB 5009.268-2016《食品安全国家标准食品中多元素的测定》第二法-电感耦合等离子体发射光谱法(inductively coupled plasma optical emission spectrometer,ICP-OES)为参照,用2种不同方法对市场上随机抽取的油炸面制品中的铝含量进行检测,同时对2种方法的检出限、精密度和准确度进行比较,通过加标回收率和质控样品来验证2种方法的准确性和可靠性。结果分光光度法的平均加标回收率为95.3%,质控样品偏离真值9.1%;ICP-OES法的平均加标回收率为100.2%,质控样品偏离真值1.6%。结论 ICP-OES法的回收率高于分光光度法,且检出限低,灵敏度高,操作过程简单,能更准确快速的对铝含量进行测定。     

Non-targeted screening of pesticides for food analysis using liquid chromatography high-resolution mass spectrometry-a review

ABSTRACT

Targeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) is a robust and reliable tool in quantitative analysis of pesticide residues in food samples. However, these methods have been only targeted to a predefined set of pesticides. Many other unexpected pesticides and/or their (bio)transformation products present in food matrices that may be harmful to consumers need to be discovered for food safety monitoring purpose. Therefore, non-targeted screening approaches using liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) have gained much attention in food monitoring recently. However, the development and implementation of non-targeted screening of potential pesticides and their (bio)transformation products in food samples are particularly challenging due to the inherent sample complexity and large quantity of MS data. To provide guidance on how to use non-targeted screening approaches for pesticide screening, three different aspects, namely, sample preparation, data acquisition and data processing, encompassed in the workflow of non-targeted screening approaches have been discussed, and current strategies, advances and challenges regarding these three aspects are reviewed. In addition, the recent application of non-targeted screening analysis of pesticide residues and their (bio)transformation products in food samples has been overviewed in this paper.     

Electronic Nose as a Tool for Monitoring the Authenticity of Food. A Review

Counterfeiting of food is recently one of the risks relevant for producers, distributors, retailers, consumers, and national governments from economic (price), health (allergens), and religious reasons. Flavour of several food products is one of the key attributes of their quality and authenticity. In the case of some foods, the aroma of a product is specific enough to discriminate an original product from its fraud or adulterated counterpart. Electronic nose (e-nose) is a rapid and powerful technique, which requires no special sample preparation to determine the aroma of a product. In the present review, the applications of different e-noses and chemometrics for determination of food authenticity including adulteration and confirmation of origin are discussed. E-noses of various configurations are a very promising tool for testing the authenticity of food products.     

快速筛选技术的评价验证

快速筛选技术是指包括样品制备在内, 能够在较短时间内出具检测结果的行为, 也称之为快速检测技术。随着我国食品安全问题广受关注, 快速筛选技术便成为研究的重点。快速检测目前主要应用于食品中农、兽药残留, 微生物致病菌, 营养成分, 不明污染物等针对食品安全的现场快速检测及常规检测。本文介绍了分子光谱法、免疫分析方法、酶抑制法和生物传感器等几种快速筛选技术的研究进展以及在食品安全检测等领域的应用。随着快速筛选技术的不断发展使得快速检测方法及其相关仪器产品种类越来越多且原理复杂, 快速检测方法的质量控制和方法验证显得尤为重要。本文重点阐述了快速筛选技术与方法的评价验证, 其主要技术参数包括: 敏感度、阴性和阳性界限值的准确性、选择性和特异性、检出限、定量限、重复性和再现性等, 并对其发展前景进行了展望。     

敞开式离子化质谱在食品安全快速筛查中的应用

敞开式离子化质谱(ambient mass spectrometry,AMS)是一种能在大气压环境中对样品进行解吸并离子化,从而获得样品表面信息的新型质谱技术。由于其具有快速、原位、实时分析等优势,近年来被广泛应用于食品安全快速筛查领域。本文从霉菌毒素类物质的检测,食品中非法添加物的快速筛查,食品本身有毒有害物质的鉴定,食品质量监控,食品组成成分分析和监测食品中的化学反应六个方面,综述了以实时直接分析(direct analysis in real time,DART)离子化技术为主的AMS技术在食品安全分析领域的应用。     

近红外光谱分析在食品检测中的最新进展

近红外光谱分析技术是一种需较少预处理的快速无损伤技术，这项技术已广泛应用于食品化学组成和物化性质分析中。简述了近红外光谱技术在食品组成成分、食品品质、食品生产和食品安全等四个方面应用的最新进展。     

HS-SPME/GC-MS Method to Characterise the Flavour of Italian Pasta: Potential Application to Assess the Quality of the Products

Food flavour, consisting of a large number of volatile compounds, has great influence on consumer acceptability and, when safety and nutritional value are guaranteed, sensory parameters become the discriminating factor in the product quality assessment which determines the differentiation on the market. The present work combines head space-solid phase micro-extraction and gas chromatography mass spectrometry techniques to analyse the volatile fraction of Italian durum wheat pasta. The aim was the optimization of an analytical method suitable to show possible differences in pasta flavour richness and identify compounds that could be used as food quality markers. Twenty-three odorants were identified and confirmed by comparing their mass spectra with those of 27 standard substances. The optimum conditions for extraction temperature and time, respectively, resulted from 70 °C and 90 min; the best recoveries were achieved with 10.5 g of sample. The developed method was applied for the relative quantitative analysis of different priced pasta to verify the technique capability to highlight possible quality differences.     

粮食中重金属检测技术研究进展

近年来接连发生的粮食重金属污染事件引发社会广泛关注。本文从样品前处理、分析检测技术等方面综述了粮食中重金属元素的分析方法。首先对当前我国粮食中重金属污染现状进行了分析,综述了重金属元素前处理的方法,包括消解法、固相萃取法、液液萃取法;并分常规检测技术和快速检测技术着重总结了各种重金属元素分析检测技术的原理、优缺点及在粮食安全中的应用。其中常规检测技术包括原子光谱法、电感耦合等离子质谱法、紫外分光光度计法,快速检测技术有电化学分析法、生物传感器法以及免疫检测技术,为保障人民群众粮食安全,积极发展粮食中重金属元素检测技术,前处理消解技术和色谱联用技术以及快速检测技术将是今后的重要发展方向。     

Rapid screening for pesticides using automated online sample preparation with a high-resolution benchtop Orbitrap mass spectrometer

For pesticide analysis in food products a common approach is to develop a fast multi-residue method that is capable of identifying and quantifying a large number of analytes in various matrices. This study demonstrates rapid screening and accurate mass confirmation of 116 pesticides in oranges and hazelnuts using an automated online sample preparation method with turbulent-flow chromatography technology coupled to a high-resolution benchtop Orbitrap? mass spectrometer. The limits of quantification (LOQs) for the majority of analytes are well below the maximum residue limit (MRL) set by the European Union and the Japanese government. The recoveries were in the range of 70-120% for over 75% of analytes in both matrices. The present methodology is suitable for routine pesticides analysis in food safety laboratories.     

多壁碳纳米管-聚醚砜复合膜净化法快速测定食品中15种农药残留

采用相转化法,把吸附材料多壁碳纳米管填充到聚醚砜中,制备多壁碳纳米管-聚醚砜复合膜。由扫描电镜观察可知,复合膜呈指状孔结构。设计简便、易于操作的复合膜过滤前处理装置,将该复合膜和装置用于食品中农药多残留快速检测的前处理中,采用超高效液相色谱-串联质谱进行测定,建立食品中15种农药的快速检测方法。结果显示:采用复合膜对样品进行快速前处理,净化效果良好,但由于复合膜中多壁碳纳米管的特殊平面环状结构,使得复合膜可能对平面型农药具有一定的吸附作用,15种农药中,2种平面型农药回收率不好,13种非平面型农药的回收率平均值在71%~118%之间,相对标准偏差在0.73%~12.87%之间(n=6)。该方法使得整个样品前处理时间从4~7 h缩短到30 min内,并具有操作简单高效、灵敏度高、环境友好、易于普及的优点,适合于食品中非平面型农药残留的快速分析测定。     

水产品产地溯源与真伪鉴别技术研究进展

随着水产品需求的迅速增长, 消费者越来越注重水产品的质量安全, 对水产品原产地的关注也日益增加。近年来, 一些不法商家为了追求高额利润, 采用虚假宣传的方式, 将普通水产品的产地标注为高档次产品的产地, 严重损害了消费者的合法权益。因此, 水产品产地溯源与真伪鉴别技术得到了广泛关注。目前, 水产品溯源与真伪鉴别技术涵盖了基于DNA条形码、核酸检测技术、质谱技术及光谱技术等多种技术手段, 这些方法通过检测水产品的核酸、元素组成、有机物质的含量等信息, 结合数学统计分析方法实现对鱼类、贝类、藻类等水产品的追溯, 以确定其产地和生长环境等信息。本文总结了元素分析法、代谢组学法、核酸检测法等水产品溯源技术, 阐述了水产品溯源技术的原理及其应用研究进展, 并对各方法应加强关注和改善的问题进行展望, 以期进一步推进水产品溯源与真伪鉴别技术在水产品质量安全领域的应用。     

微芯片技术在农产品及食品真菌毒素快速检测中的应用

真菌毒素污染的农产品及食品会对人类及牲畜的健康产生严重威胁。目前,真菌毒素的检测主要采用液相色谱-质谱联用法(liquid chromatography-mass spectrometry,LC-MS)、气相色谱-质谱联用法(gas chromatography-mass spectrometry,GC-MS)等传统检测方法。然而,这些检测方法的样品前处理过程比较繁琐、费时,并且在分析过程中还会消耗大量的有毒试剂。微芯片技术所需样品的消耗量少并且分析时间短,可实现样品的集成化、微型化以及高通量检测。微芯片技术在真菌毒素检测中的应用,弥补了上述传统检测方法的不足。本文主要综述了微芯片技术在农产品及食品真菌毒素快速检测中的应用研究进展。首先对农产品及食品中常见的真菌毒素及其毒性进行了简单介绍;接着重点对微芯片技术在真菌毒素检测中的应用进行了详细论述;最后对微芯片应用于真菌毒素检测的发展前景和挑战进行了展望。     

Applications of Computer Vision for Assessing Quality of Agri-food Products: A Review of Recent Research Advances

With consumer concerns increasing over food quality and safety, the food industry has begun to pay much more attention to the development of rapid and reliable food-evaluation systems over the years. As a result, there is a great need for manufacturers and retailers to operate effective real-time assessments for food quality and safety during food production and processing. Computer vision, comprising a nondestructive assessment approach, has the aptitude to estimate the characteristics of food products with its advantages of fast speed, ease of use, and minimal sample preparation. Specifically, computer vision systems are feasible for classifying food products into specific grades, detecting defects, and estimating properties such as color, shape, size, surface defects, and contamination. Therefore, in order to track the latest research developments of this technology in the agri-food industry, this review aims to present the fundamentals and instrumentation of computer vision systems with details of applications in quality assessment of agri-food products from 2007 to 2013 and also discuss its future trends in combination with spectroscopy.     

金黄色葡萄球菌肠毒素检测方法及前处理技术研究进展

金黄色葡萄球菌是常见的食源性致病菌之一,肠毒素是导致金黄色葡萄球菌食物中毒的最主要原因。现有肠毒素检测方法包括免疫学方法、分子生物学方法、生物传感器方法和质谱法等。各方法均存在优劣,酶联免疫学作为现有国家、行业标准推荐方法,虽然灵敏度高,但存在交叉反应,且价格昂贵。而质谱分析技术法具有高通量、专属性强等优点,已成为近年肠毒素检测技术研究热点。由于食品基质含有脂质,糖类等多种复杂成分,对肠毒素的分离与检测具有较强的干扰,因此选择恰当的样品前处理方法是实现肠毒素的准确检测的关键。本文分别从肠毒素性质、肠毒素检测方法及原理、样品前处理方法等方面对现有研究进展进行阐述。通过对现有技术方法的比较分析,基于高效液相分离技术结合质谱检测技术开发肠毒素检测方法,不仅能够从食品中实现多种肠毒素的高效分离富集,还具有灵敏度高、专属性强等优点,是未来肠毒素检测方法的主要研究方向。