Element signature analysis: its validation as a tool for geographic authentication of the origin of dried beef and poultry meat

Element concentrations of 56 poultry meat and 53 dried beef samples were determined and statistically analyzed using analysis of variance and linear discriminant analysis (LDA) to identify the single or combination of elements with the highest potential to determine the geographic origin. In order to validate the applicability of this technique, the results were additionally combined with data from an earlier assessment including 25 poultry meat and 23 dried beef samples. Validation was performed by estimating the origin of the first samples based on the data of the second, larger, dataset. Elements significantly discriminating among countries were As, Na, Rb, Se, Sr, and Tl for poultry meat and As, B, Ba, Ca, Cd, Cu, Dy, Er, Fe, Li, Mn, Pd, Rb, Se, Sr, Te, Tl, U, and V for dried beef out of about 50 elements each. The LDA gave mean correct classification rates of 77 and 79% for poultry meat and dried beef, respectively. Validation allowed identifying some, but not all, origins. For a higher discriminative power, this method should be combined with other ways of authentication.     

Tracing the geographic origin of poultry meat and dried beef with oxygen and strontium isotope ratios

Two promising isotope ratios, the δ¹⁸O of the water fraction, as extracted by azeotropic distillation, and the ⁸⁷Sr/⁸⁶Sr of the ash fraction were tested for their applicability to determine the geographic origin. In two sampling phases, in total 78 fresh poultry breast meat and 72 dried beef samples, independent from each other and originating from different countries, were analysed. The δ¹⁸O was measured with isotope ratio mass spectrometry and the isotope abundance ratio of ⁸⁷Sr/⁸⁶Sr with a multicollector inductively coupled plasma mass spectrometer. With δ¹⁸O it was possible to distinguish (p < 0.001) poultry and dried beef samples according to their country of origin. The beef data suggests that the procedure of processing is of only low additional influence on δ¹⁸O and, if so, it seems to reduce the initial between-country differences. The ⁸⁷Sr/⁸⁶Sr ratio did not give sufficient indications for differentiation by geographic origin in either poultry meat or dried beef in the smaller, first phase, data set and was therefore not further tested.     

Seasonal variation in the C,N and S stable isotope composition of retail organic and conventional Irish beef

The objective of this study was to investigate seasonal variation in the C, N and S stable isotope composition of retail organic and conventional Irish beef. A total of 242 beef samples (127 organic, 115 conventional) was collected in a one-year survey and analysed by isotope ratio mass spectrometry. The δ¹³C time series in conventional beef was significantly non-random, with a pronounced seasonal positive shift of >2‰ between December and June, whilst δ¹³C in organic beef was less variable and significantly more negative. In conventional beef, δ¹⁵N was remarkably invariant (remaining close to 7‰) throughout the year, while organic beef was more variable and also significantly lower in δ¹⁵N. The S isotope composition (δ³⁴S) exhibited a complex seasonal pattern in both types of beef. These results show that seasonal patterns can occur in the isotopic composition of beef, probably reflecting seasonality in animal feeding practices modulated by tissue turnover rates. Such seasonal variation needs to be considered in the isotopic authentication of beef and other animal-derived products.     

Reliability of stable isotope values from meat juice for the determination of the meat origin

For the determination of the origin of foods, analysis of the oxygen and hydrogen isotope composition of the food water often is of great importance, because of the differences in the isotope signature of water between different regions. However, it was reported previously that the changes in δ¹⁸O during storage of meat are of such magnitude that existing variations between regions and countries are obscured. We have investigated the δ²H and δ¹⁸O changes in meat juice after slaughtering during storage under real cold storage conditions. Our results disagree with a previous publication as we did not observe heavy isotope enrichment of meat juice during industrial cold storages. Additionally we investigated possible changes in δ¹⁸O of the meat juice during the roasting process.     

Verifying the geographical origin of beef: The application of multi-element isotope and trace element analysis

Beef samples originating from the major cattle producing regions of the world (Europe, USA, South America, Australia and New Zealand) have been analysed using IRMS and ICP-MS. C and N isotope composition of the beef defatted dry mass and H and O isotope composition of the corresponding lipid fractions were determined. It was observed that intensive maize and/or C₄ pasture feeding, during cattle production, gave rise to significant differences in the ¹³C content of beef produced in Brazil and the USA versus British beef fed predominantly on C₃ pasture and fodder. The mean δ²H‰ and δ¹⁸O‰ values of beef lipid correlated well with the latitude of production regions and the relationship between the H and O isotopic contents were found to parallel the Meteoric Water Line. These findings support the hypothesis that the systematic global variations in the ²H and ¹⁸O content of precipitation are transferred through drinking water and feed into beef lipid. Multi-element concentrations determined in the beef were combined with the stable isotope data and submitted to multivariate analysis. Six key variables (δ¹³C‰ (defatted dry mass), Sr, Fe, δ²H‰ (lipid), Rb and Se) were identified by canonical discriminant analysis as providing the maximum discrimination between beef samples on the basis of the broad geographical areas (Europe, South America and Australasia). It was concluded that the methodology in its current state can be used to provide reliable origin information, but this is dependent upon the countries under investigation.     

Pre-selection of potential molecular markers for the geographic origin of dried beef by HR-MAS NMR spectroscopy

The complexity of meat composition and the requirement of high analytical rates to prevent frauds and, in general, to assess food quality are stimuli to find analytical methods able to detect appropriate indicators of a given quality. We present here an evaluation of 1D ¹H HR-MAS NMR spectroscopy for the selection of potential molecular markers of one specific quality, geographic origin. Dried beef samples of certified origin were tested, and preliminary results on a limited sample set confirmed the good aptitude of this method for rapid food analysis, demonstrated earlier on dairy products. Fat content as well as specific metabolites, probably linked to feeding system, are shown to be good candidates for markers of origin. These results are in agreement with recent studies on the relative impact of genetic and dietary conditions on the metabolic profile of animal specimens. ¹H HR-MAS is thus an interesting tool for pre-screening potential markers, that can complement standard chemical and biochemical analysis.     

Implementation of hazard analysis critical control point in the meat and poultry industry

Abstract

Meat and poultry industries today are facing new challenges, with more complex ingredients, processes, and packaging. Consequently, controls are becoming more important as more complex processes are developed. Widespread adoption of Hazard Analysis Critical Control Point (HACCP) by the meat and poultry industry should enhance consumer confidence in its products and reduce the currently existing barriers in international trade. The purpose of this review is to present several comprehensive flow diagrams of meat and poultry products and apply HACCP principles in order to ensure food safety.     

A fast and accurate method for controlling the correct labeling of products containing buffalo meat using High Resolution Melting (HRM) analysis

The substitution of high priced meat with low cost ones and the fraudulent labeling of meat products make the identification and traceability of meat species and their processed products in the food chain important. A polymerase chain reaction followed by a High Resolution Melting (HRM) analysis was developed for species specific detection of buffalo; it was applied in six commercial meat products. A pair of specific 12S and universal 18S rRNA primers were employed and yielded DNA fragments of 220 bp and 77 bp, respectively. All tested products were found to contain buffalo meat and presented melting curves with at least two visible inflection points derived from the amplicons of the 12S specific and 18S universal primers. The presence of buffalo meat in meat products and the adulteration of buffalo products with unknown species were established down to a level of 0.1%. HRM was proven to be a fast and accurate technique for authentication testing of meat products.     

Geographical origin traceability of foxtail millet based on the combination of multi-element and chemical composition analysis

The potential approach of classifying foxtail millet according to geographical origin was investigated using mineral element and chemical composition analysis of samples from various provinces in China. Total 16 mineral elements and five chemical compositions of foxtail millets were analyzed. There were significant differences in 12 elements of millets from different regions. Notable differences were also observed for chemical composition, with Hebei samples showing higher protein content, Henan samples showing higher fat and ash contents and Shandong samples showed higher dietary fiber and amylose contents. Based on the combination of both methods, discriminant analysis provided optimal discrimination among the various geographical origins with a 95.2% classification rate. Our study provides an effective tool to trace the foxtail millet geographic origin through a combination of multi-element and chemical composition analysis.     

The use of inductively coupled plasma mass spectrometry (ICP-MS) for the determination of toxic and essential elements in different types of food samples

This paper describes a simple method for the determination of sixteen elements in food samples by using inductively coupled plasma spectrometry (ICP-MS). Prior to analysis, 100–250 mg of powdered food samples were accurately weighed into a Teflon digestion vessel. Then, 4 ml of 20% v/v concentrated nitric acid and 2 ml of hydrogen peroxide were added. Decomposition of samples was carried out in a microwave digestion system. In order to verify the accuracy and precision of the proposed method, five Standard Reference Materials from the National Institute of Standards and Technology (NIST) (Whole Egg Powder RM 8415, Rice Flour SRM 1568a, Typical Diet SRM 1548a, Wheat Flour SRM 1567a and Bovine Muscle Powder RM 8414) were analyzed. Additional validation data are provided based on the analysis of 18 different types of food samples by the proposed method and using comparative methods with AAS as the detector.     

Application of mid-infrared spectroscopy with multivariate analysis and soft independent modeling of class analogies (SIMCA) for the detection of adulterants in minced beef

Chemometric MID-FTIR methods were developed to detect and quantify the adulteration of mince meat with horse meat, fat beef trimmings, and textured soy protein. Also, a SIMCA (Soft Independent Modeling Class Analogy) method was developed to discriminate between adulterated and unadulterated samples. Pure mince meat and adulterants (horse meat, fat beef trimmings and textured soy protein) were characterized based upon their protein, fat, water and ash content. In order to build the calibration models for each adulterant, mixtures of mince meat and adulterant were prepared in the range 2–90% (w/w). Chemometric analyses were obtained for each adulterant using multivariate analysis. A Partial Least Square (PLS) algorithm was tested to model each system (mince meat + adulterant) and the chemical composition of the mixture. The results showed that the infrared spectra of the samples were sensitive to their chemical composition. Good correlations between absorbance in the MID-FTIR and the percentage of adulteration were obtained in the region 1800–900 cm^− 1. Values of R² greater than 0.99, standard errors of calibration (SEC) in the range to 0.0001–1.278 and standard errors of prediction (SEP estimated) between 0.001 and 1.391 for the adulterant and chemical parameters were obtained. The SIMCA model showed 100% classification of adulterated meat samples from unadulterated ones. Chemometric MID-FTIR models represent an attractive option for meat quality screening without sample pretreatments which can identify the adulterant and quantify the percentage of adulteration and the chemical composition of the sample.     

Potential of a custom-designed fluorescence imager combined with multivariate statistics for the study of chemical and mechanical characteristics of beef meat

The potential of fluorescence imaging to discriminate different bovine muscles in relation with animal age, muscle type, chemical and mechanical properties was examined. Twenty-four muscles of three types (Gluteus medius, Longissimus dorsi, and Semitendinosus) and two animal age groups (10-13-years old and 12-24-months old) were obtained from the carcasses of Limousin breed cows. One hundred and forty-four images were collected at three illuminating conditions (exc 320 nm, exc 380 nm, and white light) using a custom-designed imager. The image cubes were processed using “regionprops” algorithm developed earlier in order to extract image shape features (number of shapes, area, major-axis-length, eccentricity, and solidity). Extracted image shape features were processed using custom-designed programs. The results of the PLSDA performed on image shape features showed 100% good discrimination for the three types of muscles. Muscle samples were also subjected to chemical analysis (dry matter, fat, pyridinoline, total, insoluble and soluble collagen) and mechanical tests (shear stress and breaking energy). PLSR models indicated relations between extracted image shape features and mechanical properties, i.e., R² = 0.69 and RMSEV = 0.514 were observed for breaking energy for adult-animal muscles. Regarding chemical composition, image shape features allowed to predict total collagen of L. dorsi with R² = 0.61 and RMSEV = 0.756. This study has demonstrated a promising potential of the custom-designed fluorescence imager combined with multivariate statistical tools in the study of beef meat.     

Development and application of a method for the analysis of two trichothecenes: deoxynivalenol and T-2 toxin in meat in China by HPLC-MS/MS

A reliable and sensitive method was developed and successfully applied for the determination of deoxynivalenol and T-2 toxin simultaneously in pig dorsal muscle, pig back fat and chicken muscle by high performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) analysis. Limit of detection of deoxynivalenol and T-2 was 0.02 μg/kg and 0.007 μg/kg, and limit of quantification of deoxynivalenol and T-2 was 0.07 μg/kg and 0.02 μg/kg, respectively. Sixty-six meat samples were analyzed and deoxynivalenol was detected in the samples of pig back fat, with concentrations lower than 0.5 μg/kg, and T-2 toxin was detected in the samples of pig dorsal muscle, pig back fat and chicken muscle, with concentrations lower than 0.5 μg/kg. The results of sample analysis show that only trace residues of deoxynivalenol and T-2 toxin were detected in the samples analyzed.     

Utilisation of mid-infrared spectroscopy for determination of the geographic origin of Gruyère PDO and L’Etivaz PDO Swiss cheeses

The potential of mid-infrared spectroscopy (MIR), using an attenuated total reflectance (ATR) cell, was evaluated for the authentication of 25 Gruyère PDO and L’Etivaz PDO cheeses produced at different altitudes in Switzerland. In order to test the ability of MIR to authenticate the investigated cheeses, chemometric tools, such as principal component analysis (PCA) and factorial discriminant analysis (FDA), were applied to the three spectral regions of the MIR (e.g. 3000–2800 cm⁻¹, 1700–1500 cm⁻¹, and 1500–900 cm⁻¹). By applying the FDA to the first 10 principal components (PCs) of the PCA applied to each spectral regions, the best rate of correct classification was obtained in the 3000–2800 cm⁻¹ and 1500–900 cm⁻¹ spectral regions, since 90.5% and 90.9% were achieved, respectively. It can be concluded that these two spectral regions could be considered as valuable tools for the determination of the geographical origin of the investigated cheeses.     

Synthesis and application of a new functionalized resin for use in an on-line,solid phase extraction system for the determination of trace elements in waters and reference cereal materials by flame atomic absorption spectrometry

The synthesis and characterization of the resin Amberlite XAD-4 functionalized with 2,6-pyridinedicarboxaldehyde and its application in an on-line system for the preconcentration of cadmium, cobalt, copper, lead and manganese prior to determination using flame atomic absorption spectrometry (FAAS) is proposed. Metal ions retained on the modified resin were eluted using 1.0 mol L⁻¹ HNO₃ solution and aspirated directly to the nebulizer–burner system of a FAAS instrument using a flow injection system. Detection limits (3σ) were determined to be 0.13 μg L⁻¹ for Cd, 0.29 μg L⁻¹ for Cu, 0.23 μg L⁻¹ for Mn, 0.58 μg L⁻¹ for Co and 2.19 μg L⁻¹ for Pb using a 10 mL of water sample loading volume. The limits of detection would be 100 times higher with units of μg kg⁻¹ for the solid samples in which their dilution ratios as (volume/weight) were 100. Enrichment factors ranged from 23.6 to 28.9 (for Co and Mn, respectively). The proposed method was successfully applied to determination of the analytes in natural water samples and certified reference materials.     

Determination of the geographical origin of wine using joint analysis of elemental and isotopic composition. II—Differentiation of the principal production zones in france for the 1990 vintage

Stable isotope analysis of grape juices and fermented products involving 2H-NMR spectroscopy and isotope ratio mass spectroscopy was carried out in combination with elemental determinations performed by atomic absorption spectroscopy using flame and thermal ionisation. One hundred and sixty five grape samples were carefully collected in well-defined vineyards of France situated in Alsace, Burgundy, Beaujolais and the Loire Valley. Moreover, the samples from Burgundy were picked from four typical Appellations (Cǒtes de Nuits, Cǒtes de Beaune, Cǒtes Chalonnaises and Mǎconnais) in order to ‘zoom’ the approach to smaller production areas. An exhaustive statistical evaluation of the 165 ± 16 data set was carried out by analysis of variance and principal component analysis. To conclude this study, the classification of the samples in typical Appellations was carried out by discriminant analysis with a nearly 100% degree of achievement.     

药食同源植物LC-MS技术分析的研究进展

药食同源植物因其不良反应小、药用价值高、天然、安全的特点而得到广泛应用,药食同源植物化学成分的深入研究可以明确其营养价值和药用价值。近十年来,液质联用（LC-MS,liquid chromatography-mass spectrometry）技术的快速发展极大地推动了药食同源植物化学成分的研究,在药食同源植物功的功效成分分析和质量控制中得到广泛应用并逐渐成为主流技术。本文从LC-MS技术的发展和药食同源植物研究中LC-MS技术应用方法两个方面,阐述了近十年来LC-MS技术分析药食同源植物化学成分的研究进展,以期为深入研究药食同源植物提供参考。