This chapter is written to describe the concept of product testing in agri-food supply chains and the methods that are being developed to identify instances of product non-conformance with either regulatory requirements, market requirements or both. The emergence of a range of new technologies provides opportunity to build on existing product testing protocols and offer complementary alternative and rapid testing of food which can provide assurance that food products are consistently what they are purported to be. Microbiological contamination will not be considered in this chapter. Effective and targeted product testing also acts as a potential deterrent against food safety incidents and food fraud. The chapter also introduces the term “foodomics” and what this means in terms of smart agri-food supply chains.