Detection and discrimination of seven highly consumed meat species simultaneously in food products using heptaplex PCR-RFLP assay

Anticounterfeiting and Fraud Mitigation Solutions for High-value Food Products

Globalization and the increasing complexity of supply chains have allowed food fraud to expand to a great extent. Some of the most serious effects of these deceitful activities are damage to a brand's reputation and trust, economic losses, and public health risks. The usual victims of food fraud are dairy, meat, fish, and seafood products, as well as fats/oils and alcoholic drinks. The purpose of this review paper is to present an updated analysis of the currently available anticounterfeit technologies and their application to the four most fraud-affected food supply chains. An assessment that was conducted to determine when the adoption of a combination of technologies could enhance food safety and brand protection is also provided. The obtained results indicate that electronic and data-driven technologies (RFID devices and digital traceability systems) are still in their infancy in the food sectors that are subjected the most to fraudulent activities. Research is necessary to develop innovative digital and physical technologies to "outsmart" such fraudsters and to prevent their illicit actions in the food sector.

Rapid and Simultaneous Authentication of Six Laver Species Using Capillary Electrophoresis-Based Multiplex PCR

Lavers are typically consumed in dried or seasoned forms. However, commercially processed lavers can lead to seafood fraud because it is impossible to authenticate the original species based on morphological characteristics alone. In this study, we developed a capillary electrophoresis-based multiplex polymerase chain reaction (PCR) to authenticate six different laver species. The species-specific primer sets to target the chloroplast rbcL or rbcS genes were newly designed. We successfully established both singleplex and multiplex conditions, which resulted in specific amplicons for each species (N. dentata, 274 bp; N. yezoensis, 211 bp; N. seriata, 195 bp; N. tenera, 169 bp; N. haitanensis, 127 bp; P. suborbiculata, 117 bp). Moreover, the assays were sensitive enough to detect DNA ranging from 10 to 0.1 pg of DNA. The optimized capillary electrophoresis-based multiplex PCR was successfully applied to 40 commercial laver products. In addition to detecting the laver species as stated on the commercial label, the assay discovered cases where less expensive species were mixed in. With its advantageous properties, such as short amplicon size, high specificity, and superior sensitivity, this assay could be used for the authentication of the six laver species.

Identification of animal species of origin in meat based on glycopeptide analysis by UPLC-QTOF-MS

Adulteration of meat and meat products causes a concerning threat for consumers. It is necessary to develop novel robust and sensitive methods which can authenticate the origin of meat species to compensate for the drawbacks of existing methods. In the present study, the sarcoplasmic proteins of six meat species, namely, pork, beef, mutton, chicken, duck and turkey, were analyzed by one-dimensional gel electrophoresis. It was found that enolase could be used as a potential biomarker protein to distinguish between livestock and poultry meats. The glycosylation sites and glycans of enolase were analyzed by UPLC-QTOF-MS and a total of 41 glycopeptides were identified, indicating that the enolase N-glycopeptide profiles of different meats were species-specific. The identification models of livestock meat, poultry and mixed animal were established based on the glycopeptide contents, and the explanation degree of the three models was higher than 90%. The model prediction performance and feasibility results showed that the average prediction accuracy of the three models was 75.43%, with the animal-derived meat identification model showing superiority in identifying more closely related species. The obtained results indicated that the developed strategy was promising for application in animal-derived meat species monitoring and the quality supervision of animal-derived food.

Advances in the authentication of collagen products based on DNA technology

Collagenous products are making their way into consumer markets such as foods, nutraceuticals, cosmetics and pharmaceuticals increasingly. Collagen in a large family of proteins is ubiquitous in metazoan. The most effective way to identify biological samples including collagen is DNA technology indisputably. However, the DNA content of collagen mostly derived from connective tissue is relatively less, and commercial collagen products are usually subjected to some harsh treatments in the production process, which makes DNA damage more serious, thus tracing their origin becomes a huge challenge. At present, DNA enrichment mainly relies on silica based centrifugal columns after extraction by classical phenol chloroform method. For improving the amplification of DNA fragments, small amplicons are designed based on more stable mitochondrial genes, such as cytochrome b gene (cytb). In addition to conventional PCR for DNA amplification, some new PCR techniques have also been developed, such as DNA barcoding techniques, PCR-Southern hybridization and fluorescent PCR. These PCR techniques have their pros and cons, and are mainly used in the identification of gelatin at present. The development of a complete set of DNA authentication is of great significance for the control of collagen products quality and will contribute to sustainable development of collagen industry.

A Novel Universal Primer Multiplex Real-Time PCR (UP-M-rtPCR) Approach for Specific Identification and Quantitation of Cat, Dog, Fox, and Mink Fractions Using Nuclear DNA Sequences

Adulteration of meat with carnivorous animals (such as cats, dogs, foxes, and minks) can cause ethical problems and lead to disease transmission; however, DNA quantitative methods for four carnivorous species in one tube reaction are still rare. In this study, a carnivore-specific nuclear DNA sequence that is conserved in carnivorous animals but has base differences within the sequence was used to design universal primers for its conserved region and corresponding species-specific probes for the hypervariable region. A novel universal primer multiplex real-time PCR (UP-M-rtPCR) approach was developed for the specific identification and quantitation of cat, dog, fox, and mink fractions in a single reaction, with a 0.05 ng absolute limit of detection (LOD) and 0.05% relative LOD. This approach simplifies the PCR system and improves the efficiency of simultaneous identification of multiple animal-derived ingredients in meat. UP-M-rtPCR showed good accuracy (0.48-7.04% relative deviation) and precision (1.42-13.78% relative standard deviation) for quantitative analysis of cat, dog, fox, and mink DNA as well as excellent applicability for the evaluation of meat samples.

Rapid and sensitive detection of box turtles using an electrochemical DNA biosensor based on a gold/graphene nanocomposite

The Southeast Asian box turtle, Cuora amboinensis, is an ecologically important endangered species which needs an onsite monitoring device to protect it from extinction. An electrochemical DNA biosensor was developed to detect the C. amboinensis mitochondrial cytochrome b gene based on an in silico designed probe using bioinformatics tools, and it was also validated in wet-lab experiments. As a detection platform, a screen-printed carbon electrode (SPCE) enhanced with a nanocomposite containing gold nanoparticles and graphene was used. The morphology of the nanoparticles was analysed by field-emission scanning electron microscopy and structural characteristics were analysed by using energy-dispersive X-ray, UV-vis, and Fourier-transform infrared spectroscopy. The electrochemical characteristics of the modified electrodes were studied by cyclic voltammetry, differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy. The thiol-modified synthetic DNA probe was immobilised on modified SPCEs to facilitate hybridisation with the reverse complementary DNA. The turtle DNA was distinguished based on hybridisation-induced electrochemical change in the presence of methylene blue compared to their mismatches, noncomplementary, and nontarget species DNA measured by DPV. The developed biosensor exhibited a selective response towards reverse complementary DNAs and was able to discriminate turtles from other species. The modified electrode displayed good linearity for reverse complementary DNAs in the range of 1 × 10-11-5 × 10-6 M with a limit of detection of 0.85 × 10-12 M. This indicates that the proposed biosensor has the potential to be applied for the detection of real turtle species.

Heat-Treated Meat Origin Tracing and Authenticity through a Practical Multiplex Polymerase Chain Reaction Approach

Meat adulteration have become a global issue, which has increasingly raised concerns due to not only economic losses and religious issues, but also public safety and its negative effects on human health. Using optimal primers for seven target species, a multiplex PCR method was developed for the molecular authentication of camel, cattle, dog, pig, chicken, sheep and duck in one tube reaction. Species-specific amplification from the premixed total DNA of seven species was corroborated by DNA sequencing. The limit of detection (LOD) is as low as 0.025 ng DNA for the simultaneous identification of seven species in both raw and heat-processed meat or target meat: as little as 0.1% (w/w) of the total meat weight. This method is strongly reproducible even while exposed to intensively heat-processed meat and meat mixtures, which renders it able to trace meat origins in real-world foodstuffs based on the authenticity assessment of commercial meat samples. Therefore, this method is a powerful tool for the inspection of meat adulterants and has broad application prospects.

Detection and characterization of meat adulteration in various types of meat products by using a high-efficiency multiplex polymerase chain reaction technique

Identification of meat authenticity is a matter of increasing concerns due to religious, economical, legal, and public health reasons. However, little is known about the inspection of eight meat species in one tube reaction due to technological challenge of multiplex polymerase chain reaction (PCR) techniques. Here, a developed multiplex PCR method can simultaneously authenticate eight meat species including ostrich (753 bp), cat (564 bp), goose (391 bp), duck (347 bp), chicken (268 bp), horse (227 bp), dog (190 bp), and sheep (131 bp). The detectable deoxyribonucleic acid (DNA) contents for each target species was as low as 0.01 ng in both raw and heat-treated meat or target meat down to 0.1% (w/w) of total meat weight reflecting high stability of the assay in heat processing condition, indicating that this method is adequate for tracing meat origin in real-world meat products, which has been further validated by authenticity assays of commercial meat products. Overall, this method is a powerful tool for accurate evaluation of meat origin with a good application foreground.

Collagen Extraction from Animal Skin

Simple Summary

Collagen is useful in many applications including cosmetics, medicine, yarn production and packaging. Collagen can be recovered from skins of animals raised for meat. Here, we review methods for the extraction and purification of collagen from animal skins.

Abstract

Collagen is the most abundant structural protein in animals. It is the major component of skin. It finds uses in cosmetics, medicine, yarn production and packaging. This paper reviews the extraction of collagen from hides of most consumed animals for meat with the focus on literature published since 2000. The different pretreatment and extraction techniques that have been investigated for producing collagen from animal skins are reviewed. Pretreatment by enzymatic, acid or alkaline methods have been used. Extraction by chemical hydrolysis, salt solubilization, enzymatic hydrolysis, ultrasound assisted extraction and other methods are described. Post-extraction purification methods are also explained. This compilation will be useful for anyone wishing to use collagen as a resource and wanting to further improve the extraction and purification methods.

Molecular Authentication of Twelve Meat Species Through a Promising Two-Tube Hexaplex Polymerase Chain Reaction Technique

Frequent meat frauds have aroused significant social attention. The aim of this study is to construct a two-tube hexaplex polymerase chain reaction (PCR) method offering accurate molecular authentication of twelve meat species in actual adulteration event. Deoxyribonucleic acid (DNA) sequencing demonstrates that designed primers can specifically amplify target species from genomic DNA mixture of six species in each tube reaction, which showed 100% accuracy of horse (148 bp), pigeon (218 bp), camel (283 bp), rabbit (370 bp), ostrich (536 bp), and beef (610 bp) as well as turkey (124 bp), dog (149 bp), chicken (196 bp), duck (277 bp), cat (380 bp), and goose (468 bp). A species-specific primer pair produced the target band in the presence of target genomic DNA but not non-target species. Through multiplex PCR assays with serial concentration of the DNA mixture of six species in each PCR reaction, the detection limit (LOD) of the two-tube hexaplex PCR assay reached up to 0.05–0.1 ng. Using genomic DNA isolated from both boiled and microwave-cooked meat as templates, PCR amplification generated expected PCR products. These findings demonstrate that the proposed method is specific, sensitive and reproducible, and is adequate for food inspection. Most importantly, this method was successfully applied to detect meat frauds in commercial meat products. Therefore, this method is of great importance with a good application foreground.

A Machine Learning Method for the Quantitative Detection of Adulterated Meat Using a MOS-Based E-Nose

Meat adulteration is a global problem which undermines market fairness and harms people with allergies or certain religious beliefs. In this study, a novel framework in which a one-dimensional convolutional neural network (1DCNN) serves as a backbone and a random forest regressor (RFR) serves as a regressor, named 1DCNN-RFR, is proposed for the quantitative detection of beef adulterated with pork using electronic nose (E-nose) data. The 1DCNN backbone extracted a sufficient number of features from a multichannel input matrix converted from the raw E-nose data. The RFR improved the regression performance due to its strong prediction ability. The effectiveness of the 1DCNN-RFR framework was verified by comparing it with four other models (support vector regression model (SVR), RFR, backpropagation neural network (BPNN), and 1DCNN). The proposed 1DCNN-RFR framework performed best in the quantitative detection of beef adulterated with pork. This study indicated that the proposed 1DCNN-RFR framework could be used as an effective tool for the quantitative detection of meat adulteration.

Single nucleotide polymorphism-based methodology for authentication of bovine, caprine, ovine, camel, and donkey meat cuts

To guarantee food safetyand sustainability, it is necessary to verify meat authenticity. This study focused on the development of single nucleotide polymorphism-based polymerase chain reaction-restriction fragment length polymorphism (SNP-based PCR-RFLP) and forensically informative nucleotide sequence (FINS) methodologies based on PCR amplification of the mitochondrial 12S rRNA gene for discrimination of six red meat species, that is, cattle, buffalo, goat, sheep, camel, and donkey. FINS allowed the unambiguous identification of all species analyzed. In addition, six SNPs, where a restriction site for TasI could be localized using a preliminary in silico analysis, gave a unique RFLP pattern for each species. The results revealed a low level of species substitution (8%) in the tested meat samples. In particular, one buffalo and goat samples have been substituted with cow and sheep, respectively. Finally, the developed techniques herein showed high potentials to be routinely used as reliable and fast tools to avoid meat species substitutions. PRACTICAL APPLICATION: This research deals with genetic techniques to trace meats. This kind of research helps the concerned agencies to build capacity to safeguard consumer sentiments as well as providing better market access and better food price and quality for the consumer.