This book focuses on the development of functional nucleic acids and their applications of molecular detection methods in the context of food safety. The book has been expanded to 24 chapters based on the first edition including five newly-added chapters, of which involving the systematic introduction of currently-fashionable functional nucleic acid elements, the basic mechanism of diverse amplification technologies, and the novel design strategies of detection methods from the latest research findings for food safety. Offering a comprehensive overview of nucleic acids detection method in food safety for professionals and members of the public interested in this area.