Authentication Nursel Söylemez Milli · Halal authentication · porcine detection · food fraud · 2 min read
Halal food refers to products that are permissible for consumption according to Islamic dietary law. Halal requirements cover the source of raw materials, slaughter methods and the absence of prohibited substances such as pork, its derivatives and alcohol, as well as the prevention of cross-contamination during processing. The global halal food market has grown considerably, and the increasing complexity of supply chains has raised the risk of intentional and unintentional non-compliance. Reliable analytical technologies are therefore needed to support certification bodies, regulatory authorities and industry.
DNA-based methods are the most widely used approaches for detecting porcine material. Polymerase chain reaction (PCR) targeting species-specific mitochondrial genes, such as cytochrome b, is commonly applied because mitochondrial DNA is present in many copies and is relatively stable during processing. Real-time PCR enables sensitive and quantitative detection, while droplet digital PCR allows absolute quantification without standard curves and offers high precision at low concentrations. Isothermal amplification techniques such as loop-mediated isothermal amplification are being developed for rapid on-site testing. However, DNA degradation in highly processed products and the difficulty of relating DNA content to actual meat content remain limitations.
Protein-based methods offer complementary information. Enzyme-linked immunosorbent assays are used for rapid screening, although heat treatment can alter target proteins. Mass spectrometry-based proteomics, using liquid chromatography–tandem mass spectrometry or MALDI-TOF mass spectrometry, allows species-specific marker peptides to be identified. Peptide markers derived from heat-stable proteins can be detected even in processed products, and these methods are particularly valuable for detecting porcine gelatin and collagen.
Spectroscopic techniques, including Fourier transform infrared, near-infrared and Raman spectroscopy, combined with chemometrics, provide rapid and non-destructive screening. Analysis of fatty acid profiles by gas chromatography and differential scanning calorimetry has also been used to differentiate lard from other fats.
In recent years, sensor-based systems have emerged as promising rapid screening tools. Electronic noses using gas sensor arrays capture the volatile profile of meat samples, and machine learning models can be trained to discriminate pure products from those adulterated with pork. Low-cost, temperature-modulated metal oxide sensors offer the potential for portable devices suitable for use at inspection points and retail settings.
Halal authentication also includes the detection of ethanol and other non-permissible additives in foods and beverages, for which chromatographic and sensor-based methods are applied. Verification of slaughter practices, such as stunning and bleeding conditions, is more difficult to assess analytically and still relies largely on documentation and inspection.
An effective halal control strategy is expected to combine rapid screening methods with confirmatory laboratory techniques, supported by traceability systems and harmonized international standards. Further work on method validation, reference materials and inter-laboratory comparisons is needed to increase confidence in halal authentication results.