Validation of a Forensic Method to be used in Food Fraud Investigation

Abstract

Food fraud is the act in which food is purposefully mislabeled, adulterated, or contaminated, often to make up a percentage of a missing substance when the product is being made. It is often done purposefully to mislead consumers into thinking some ingredient is or is not present in the food, which can be hazardous to the consumer. This project aimed to validate a forensic domestic animal species reference ladder and multiplex PCR kit that can be used in animal investigations, with a focus on food fraud. A multiplex PCR protocol targeting mitochondrial DNA (mtDNA) markers and a species reference ladder can quickly identify DNA from chicken, cow, sheep, turkey, goat, horse, dog, and cat. To validate the kit, it was tested on five different brands of dog food, specifically four brands of kibble alongside a canned wet stew dog food. DNA extraction was performed using the QIAamp MinElute Column kit or the Qiagen EZ1 investigator kit, then DNA quantification, multiplex PCR, gel electrophoresis, and capillary electrophoresis to build species mtDNA profiles for each food’s contents. Results from one dog food kibble yielded some speculation as DNA for sheep and goat contents not listed in the ingredients were detected using both the gel and capillary electrophoresis.