A novel real-time polymerase chain reaction method for the qualitative detection of pistachio in food

In order to provide an appropriate method for the detection of pistachio (Pistacia vera) in food products, a novel real-time PCR was developed. The pistachio-specific primers and the TaqMan fluorogenic probe were designed to target the internal transcribed spacer between 18S ribosomal RNA and 5.8S ribosomal RNA genes. Using dilutions of the pistachio DNA, the intrinsic detection limit of the method was determined to be 0.012 pg. At specificity testing, the method was positive for 11 pistachio varieties and negative for 26 plant and animal species used in food industry. A detection limit of 0.0004% (w/w) was determined for pistachio nuts in model pastry. Practical applicability of the elaborated method was tested by the analysis of 44 food samples, out of which 7 food products were identified as containing undeclared pistachio. The developed real-time PCR may be utilized for sensitive and selective detection of pistachio in food products.