CHAPTER 3: DNA Extraction from Food Matrices¹

DNA isolation is the process of purification of DNA from a sample, using the combination of both physical and chemical methods. DNA isolation was first reported to have been performed in 1869 by the Swiss physician Friedrich Miescher during his experiments to elucidate the building blocks of life. Since the time of Miescher, DNA extraction has become a relatively routine procedure in molecular biology and forensic analyses. A number of different approaches have been developed to enable the extraction of DNA from a wide variety of matrices. Numerous commercial kits are also available for performing the extraction of DNA and other nucleic acids, and selecting an appropriate method may provide cost-savings compared with having to optimise a particular extraction procedure. This chapter provides an introduction to DNA extraction and highlights key stages in the process and possible problems that may be encountered. In addition, guidance and best practice are provided in order to assist the reader in selecting the method most appropriate to their needs and selection of approaches to use to determine the quantity and quality of the DNA extracted.