Food authentication by PCR-based methods

Food authenticity is presently a subject of great concern to food authorities, as the incorrect labelling of foodstuffs can represent a commercial fraud. The implication of misleading labelling can be much more important concerning the presence of potentially allergenic foods. The need to support food labelling has provided the development of analytical techniques for the analysis of food ingredients. In the last years, several methods based on polymerase chain reaction (PCR) have been proposed as useful means for identifying species of origin in foods, as well as food allergens and genetically modified organisms (GMO), due to their high specificity and sensitivity, as well as rapid processing time and low cost. This work intends to provide an updated and extensive overview on the PCR-based methods for food authentication, including also methods for allergens and GMO the detection in foods.     

食品组学技术在食品真伪鉴别和溯源方面应用进展

食品真伪鉴别和溯源技术是保障食品安全的重要手段。食品鉴别和溯源技术是对食品的真伪、产地和来源等相关信息进行分析及追溯,在食品质量与安全领域中占据强有力的地位。随着食品掺假频发、掺假手段多样,传统检测方法已不能满足食品的质量与安全管理要求,因此亟须发展新型快速准确的食品鉴别和溯源技术。食品组学是近年新兴的采用基因组学、转录组学、蛋白质组学及代谢组学等组学技术系统研究食品的营养与安全的一类技术,因其强大的物质鉴定功能,可以为食品鉴别和溯源提供科学依据和技术支撑。本文对食品组学技术在食品真伪鉴别和溯源方面的应用进展进行了综述,并对未来食品组学技术的发展趋势进行了展望,以期为食品质量与安全控制提供技术参考,保障人民身体健康和生活质量。     

Analytical methods combined with multivariate analysis for authentication of animal and vegetable food products with high fat content

BackgroundFood fraud is described as a violation of food law, which is intentionally committed to get an economic or financial gain through the consumer's swindle resulting in multi-million business and posing a public health threat. The main fraudulent practices are mislabelling of composition, certificates of origin, health claims, and artificial increases in weight or volume caused by replacement, dilution, addition or removal of some ingredients. Hardly 68% of the food fraud violations are produced in animal and vegetable products with high fat content (27% meat, 13% fish, 11% oils, 10% dairy products, 4% nuts and seeds and 3% animal by-products) becoming a crucial issue for food processing industries.Scope and approachThe present review focuses on the main authentication techniques and methods employed to clarify the authenticity of both animal and vegetable fat food products emphasizing the importance of the use of robust and reliable analytical techniques combined with multivariate analyses.Key findings and conclusionsTargeted approaches, such as chromatography and DNA-based methods, combined with multivariate analysis have shown high accuracy, sensitivity and selectivity, allowing the simultaneous evaluation of multiple analytes. In addition, non-target methods, such as those based on spectroscopic techniques, have been used to establish the geographic origin of food products with quick response, low cost, non-destructive character and also offering the possibility to be miniaturized.     

Invited review: Authentication of milk by direct and indirect analysis of triacylglycerol molecular species

Milk, milk-based products, and milk derivatives represent an important group of food commodities, with high nutritional value and widely consumed by large segment of consumers, including pregnant women, newborns, children, and the elderly. Food authentication is a rapidly growing field because of increasing consumer awareness regarding food quality and safety. This review attempts to critically summarize the status of direct and indirect analysis of the molecular species of triacylglycerols (TAG) used to assess the authenticity of milk. Identification and quantification of TAG molecular species in milk fat can be accurately performed even though analytical approaches focused on fraud evaluation should be developed. Recent analytical breakthroughs and novel techniques are discussed, along with their applications in milk authentication.     

食品真实性关键技术在监管科学领域的研究建议

食品真实性是食品安全的一个重要研究领域,也是食品安全战略发展的重要方面。本文提出了在综合监管科学范畴的监管模式下,通过监督管理科学化、技术化和规范化并结合真实性识别技术的研究,对潜在风险进行有效的技术鉴别;通过供应链脆弱性评估和多种技术甄别手段的研究,建立典型高值动植物食品的同位素、基因、多态性识别及整体检测等技术和食品供应链特性的脆弱性平台体系,从而解决食品真实性中多样性差异、循因手段匮缺、行为确定难等问题,为食品安全监管提供有效的科技支撑。随着各项鉴别技术的发展和真伪鉴别监管平台的建立,食品欺诈和真实性问题必将得到有效的解决。     

Advances in high-resolution mass spectrometry based on metabolomics studies for food – a review

Food authenticity becomes a necessity for global food policies, since food placed in the market without fail has to be authentic. It has always been a challenge, since in the past minor components, called also markers, have been mainly monitored by chromatographic methods in order to authenticate the food. Nevertheless, nowadays, advanced analytical methods have allowed food fingerprints to be achieved. At the same time they have been also combined with chemometrics, which uses statistical methods in order to verify food and to provide maximum information by analysing chemical data. These sophisticated methods based on different separation techniques or stand alone have been recently coupled to high-resolution mass spectrometry (HRMS) in order to verify the authenticity of food. The new generation of HRMS detectors have experienced significant advances in resolving power, sensitivity, robustness, extended dynamic range, easier mass calibration and tandem mass capabilities, making HRMS more attractive and useful to the food metabolomics community, therefore becoming a reliable tool for food authenticity. The purpose of this review is to summarise and describe the most recent metabolomics approaches in the area of food metabolomics, and to discuss the strengths and drawbacks of the HRMS analytical platforms combined with chemometrics.     

Authentication of meat and meat products

In recent years, interest in meat authenticity has increased. Many consumers are concerned about the meat they eat and accurate labelling is important to inform consumer choice. Authentication methods can be categorised into the areas where fraud is most likely to occur: meat origin, meat substitution, meat processing treatment and non-meat ingredient addition. Within each area the possibilities for fraud can be subcategorised as follows: meat origin—sex, meat cuts, breed, feed intake, slaughter age, wild versus farmed meat, organic versus conventional meat, and geographic origin; meat substitution—meat species, fat, and protein; meat processing treatment—irradiation, fresh versus thawed meat and meat preparation; non-meat ingredient addition—additives and water. Analytical methods used in authentication are as diverse as the authentication problems, and include a diverse range of equipment and techniques. This review is intended to provide an overview of the possible analytical methods available for meat and meat products authentication. In areas where no authentication methods have been published, possible strategies are suggested.     

液相色谱-高分辨质谱技术在食品掺假鉴别研究中的应用

食品欺诈是指蓄意对食品进行虚假描述,造成该食品的宣称与其真实属性不符的行为。食品掺假是食品欺诈最为常见的表现形式。在众多食品欺诈事件中,所占比例较大的是冒充、稀释、非法添加和非标注成分这4 类掺假行为。随着食品加工方式的多样化、贸易的全球化和供应链的复杂化,食品掺假愈发隐蔽,难以用常规靶向分析手段实现掺假鉴别,因此,非靶向分析技术逐渐成为食品掺假鉴别研究的热点。综上,本文重点综述了基于液相色谱串联高分辨质谱的组学分析技术在食品掺假鉴别研究领域的应用。     

Nontargeted Analytical Methods as a Powerful Tool for the Authentication of Spices and Herbs: A Review

Food fraud in herbs and spices is an important topic, which has led to new technologies being studied as potential tools for fraud identification. Nontargeted technologies have proven to be a useful tool for the authentication of herbs and spices. The present review focuses on the use of near‐infrared, hyperspectral imaging, Fourier‐transform infrared, Raman, nuclear magnetic resonance, and electron spin resonance spectroscopy for the authentication of spices, which includes the determination of origin and irradiated spices and the identification of adulterants. The methods developed based on vibrational spectroscopy combined with chemometric techniques seem to be promising tools for determining the presence of adulterants and contaminants in herbs and spices. On the other hand, nuclear magnetic resonance seems to be the most efficient technology to determine the origin of herbs and spices although, for some cases, studies with near‐infrared spectroscopy can be a viable substitute. Electron spin resonance spectroscopy is the technique par excellence used for the authentication of irradiated herbs and spices, so its use should be expanded to many more spices’ varieties. Portable devices are preferred by those involved in the food industry, due to its manageability and low cost. Data fusion and big data are shown as promising tools for spice fraud control. In conclusion, spectroscopic techniques show a great efficiency to authenticate spices, although their evaluation must be expanded to other spice varieties, to new strategies of data analysis (as data fusion and big data), and to the use of portable devices.     

Review on metabolomics for food authentication

European and global food policies require that food put on the market is authentic, which means that the label declaration matches the composition and provenance of the food item. During the last decades conventional approaches such as the determination of certain major and minor components by wet chemistry of chromatographic methods have been used for food authentication. Although many of the traditional methods are still used because they are part of product standards, new approaches that could complement existing methodologies, such as metabolomics are emerging in food authentication applications. Metabolomics aims to study multiple metabolites in a cell, a tissue or an organism. The main advantage of metabolomic applications in food authentication makes use of its untargeted nature, which can enable the detection of emerging frauds. The purpose of this review is to summarise and describe the recent metabolomic applications in the area of food authentication and to discuss its current limitations and future potential.     

稳定同位素技术在蜂蜜真实性溯源中的研究进展

蜂蜜作为一种纯天然的食品,因丰富的营养价值以及良好的保健功效而深受消费者喜爱。然而,随着近年来蜂蜜消费量的不断增多,蜂蜜掺假、以次充好等现象日益严重。因此,蜂蜜的真实性溯源研究也变得更为迫切。稳定同位素技术是食品真实性溯源的有效的技术之一,在蜂蜜的真实性溯源研究方面也有较多成果。本文综述了稳定同位素技术在蜂蜜掺假、产地鉴别、品种识别方面的研究进展并分析该技术的优点与不足,为进一步推进蜂蜜的真实性溯源研究提供参考。     

代谢组学在食品科学中的应用进展

代谢组学分析主要集中于对小分子代谢物综合分析,是对代谢靶标分析、代谢轮廓分析以及代谢指纹分析的进一步深化和融合。传统的食品分析主要分析蛋白质、脂肪、碳水化合物等,通过代谢组学技术,可在一种食品中检测到成百上千种不同的化学成分,从而为食品的鉴别、安全、加工、营养研究等提供更强大的数据支撑。文章综述了代谢组学的分析技术、样品制备、数据分析方法,并介绍了代谢组学技术在食品营养、食品质量鉴别和食品风味研究方面的应用,旨在为食品代谢组学研究及应用提供参考。     

代谢指纹分析及其在食品科学中的应用

代谢指纹分析是代谢组学的重要研究手段之一,它具有快速、高通量、全局分析的特点。文中在总结国内外近几年来有关代谢指纹分析研究开发与应用文献的基础上,对其概念与分类、分析流程及其在营养代谢性标记物研究、物质代谢规律研究、膳食调查与评价、食品原料差异性鉴别、食品质量评价与追溯等方面的应用,并对该技术在食品科学中应用进行了综述。     

基于代谢组学技术的玛咖产地鉴别

采用代谢组学的方法,基于超高效液相色谱-四极杆串联飞行时间质谱对不同产地的玛咖进行产地鉴别和各产地代谢物差异分析。通过正交偏最小二乘判别分析成功区分玛咖的5 个产地,并对各个产地玛咖的代谢物进行靶标和非靶标代谢组学分析,其中靶标代谢组学分析共鉴定出28 种代谢物,包括玛咖酰胺、玛咖烯、芥子油苷、生物碱、甾醇、多酚和黄酮,非靶标代谢组学分析鉴定出玛咖的产地标志物。结果表明代谢组学方法可以用于玛咖产地鉴别以及全组分的鉴定。     

Pattern recognition analysis on nutritional profile and chemical composition of edible bird’s nest for its origin and authentication

Authenticity of food is of great importance to ensure food safety and quality, and to protect consumer rights. A rapid and accurate method for authentication of edible bird’s nest (EBN) was proposed by using nutritional profile and chemical composition, and pattern recognition analysis. The authentication of EBN includes identification and classification of EBN by production origin (houses or caves), species origin (Aerodramus fuciphagus or Aerodramus maximus) and geographical origin (Peninsular Malaysia or East Malaysia) based on their active compositional content. Three pattern recognition methods, principal component analysis (PCA), hierarchical cluster analysis (HCA) and linear discriminant analysis (LDA), were employed to develop classification models for authentication of EBN origins. Compared to PCA and HCA, LDA is more accurate and efficient in distinguishing EBN by different production, species, and geographical origins, having classification ability of 100% and prediction ability of 92% as validated by cross-validation method. The key chemical markers for production origin differentiation are total phenolic content, zinc, valine, and calcium, while for species origin discrimination are sialic acid, serine, phenylalanine and valine, and for geographical origin differentiation are arsenic and mercury. The findings suggest that nutritional and chemical profiles combined with pattern recognition analysis are promising strategy for rapid authentication of EBN and its products.     

色谱-质谱联用的食品组学技术在食品科学研究中的应用

食品组学是近年来新兴的利用基因组学、转录组学、蛋白质组学及代谢组学等系统生物学的分析思路和方法研究食品科学的一类技术,被广泛用于食品营养、食品安全及食品溯源等研究中。色谱与质谱的联用将色谱对复杂生物体系的高分离能力与质谱的高灵敏度、高分辨率、高选择性等优点相结合,具有分析速度快、定性定量结果准确、样品用量少等特点,是目前食品组学研究中一种强有力的检测技术。本文综述了基于色谱-质谱联用的食品组学技术的分析流程及该技术在食品营养品质、食品加工及贮藏、食品溯源及真伪鉴别、食品中农药残留、食品过敏原五个方面的应用,并提出了该技术的发展趋势及展望,旨在为食品科学与质量安全研究提供理论参考。     

Potential DNA markers as a rapid tracing tool for animal adulterants in vegetarian food

DNA-based methods are rapid, cost-effective and broadly applicable approaches for food authentication. Recently, the requirements for food safety and food integrity have increased with improved quality of life. Methodologies regarding food authentication based on DNA analysis are more commonly being used. With the increasing number of vegetarians, searching for markers for blind identification across kingdom species, such as an ingredient of animal origin in vegetarian food, would be valuable and attractive. Using bioinformatic analysis of an existing data source composed of 481 ultraconserved sequences, we selected 6 new candidate DNA segments that exist in most vertebrates but that do not exist in plants. Then, primers were designed for all of the candidate DNA markers, and DNA samples isolated from cow, pig, chicken, duck, soy bean, rice, pepper, wheat, sunflower and colza were amplified using each primer pair. None of the plant DNA samples generated a PCR product, while the DNA samples of animal origin were amplified successfully using 5 of the candidate segment primers; the 6th segment primer failed to amplify the DNA and was discarded. Moreover, a simulation experiment containing a plant product contaminated by an animal component indicated that the candidate DNA markers can be used for the rapid detection of animal adulterants in vegetarian products with a promising 5% detection limit. The identified candidate DNA markers for the blind identification of animal adulteration in vegetarian food may be highly desirable in the vegetarian food market, and these markers may facilitate the study of molecular technology for food authentication.     

Recent applications of multivariate data analysis methods in the authentication of rice and the most analyzed parameters: A review

Rice is one of the most important staple foods around the world. Authentication of rice is one of the most addressed concerns in the present literature, which includes recognition of its geographical origin and variety, certification of organic rice and many other issues. Good results have been achieved by multivariate data analysis and data mining techniques when combined with specific parameters for ascertaining authenticity and many other useful characteristics of rice, such as quality, yield and others. This paper brings a review of the recent research projects on discrimination and authentication of rice using multivariate data analysis and data mining techniques. We found that data obtained from image processing, molecular and atomic spectroscopy, elemental fingerprinting, genetic markers, molecular content and others are promising sources of information regarding geographical origin, variety and other aspects of rice, being widely used combined with multivariate data analysis techniques. Principal component analysis and linear discriminant analysis are the preferred methods, but several other data classification techniques such as support vector machines, artificial neural networks and others are also frequently present in some studies and show high performance for discrimination of rice.     

基于气相色谱-质谱联用技术的代谢组学在农产品产地溯源中的应用

随着人们生活水平的提高,人们对于食品安全也提出了更高的要求。农产品产地溯源不仅能保证农产品的真实性、维护农产品市场的稳定,还是确保食品质量安全、保护消费者权益的必要手段。建立高效的食品溯源体系是保证食品质量安全的关键。气相色谱-质谱(gas chromatography-mass spectrometry,GC-MS)联用技术是代谢组学研究的重要技术之一,因其效率高、灵敏度高、稳定性强等优点,近年来被广泛应用于农产品产地溯源研究中。本文通过近5年来的主要文献分析,对GC-MS的代谢组学研究进展及其在谷物、肉制品、油类、果蔬类农产品产地溯源中的应用进行了全面的综述,并对今后农产品产地溯源的研究进行了展望。以期为我国农产品溯源体制的建立提供借鉴,推动GC-MS代谢组学技术在食品溯源中的应用。     

Melamine detection in milk using vibrational spectroscopy and chemometrics analysis: A review

Major advances in the field of chemometrics combined with the use of vibrational spectroscopy have proven essential for the identification and quantification of food contaminants. These techniques, which have guided the work of regulatory agencies overlooking the food industry, can be readily applied to monitor food processing, quality control, and quality assurance. These processes can ensure product authenticity with respect to variety, geographical origin, and presence or absence of contaminants. Food analysis by vibrational spectroscopy provides overall chemical composition of the tested food sample; therefore, it is widely considered to be a highly reliable and empirical fingerprints of that samples. In 2008, melamine adulteration of milk powder in China resulted in devastatingly adverse effects for both consumers and the overall Chinese economy at large. As a result, regulatory agencies have markedly increased their interest in using fast, reliable, and accurate methods for identifying food contaminants. In this article, we provide a detailed overview of the uses of vibrational spectroscopy methods and chemometrics for the detection and quantification of melamine in dairy products.