Detection of pig derivatives in food products for halal authentication by polymerase chain reaction-restriction fragment length polymorphism

A method for detection of the presence of pig derivatives in three types of food products - sausages and casings, bread and biscuits -using polymerase chain reaction-restriction fragment length polymorphism (PCR-PFLP) analysis of a conserved region in the mitochondrial (mt) cytochrome b (cyt b) gene was developed. Genomic DNA of sausages and casings, bread and biscuits were extracted. The genomic DNA from the food products were found to be of good quality for the sausages and produced clear PCR products on the amplification of the mt cyt b gene of approximately 360 base pairs (bp). However, no genomic DNA was detected from the casing samples and poor quality of genomic DNA was extracted from bread and biscuits. No amplification of mt cyt b gene was produced from bread and biscuit samples. To differentiate between samples, the amplified PCR products were digested with restriction enzyme (RE) BsaJI, resulting in species-specific RFLP. The cyt b PCR-RFLP species identification assay gave excellent results for detection of pork adulteration in food products and is a potentially reliable technique to avoid species adulteration or fraudulent species substitution for halal authentication. (c) 2007 Society of Chemical Industry.