SciFinder is useful for finding articles in food chemistry; Compendex for food engineering including food safety, packaging and industrial processes; Agricola for agriculture and agri-food literature, including policy issues; and Toxline for food contaminants, safety measures, and toxicological analysis. Scopus and Web of Science are large multidisciplinary databases.
Web of Science does not provide controlled vocabulary, but uses author-supplied keywords. SciFinder uses phrase-searching. Both allow you to refine results by language, type of article, author, institution, etc.
SciFinder's focus is the chemical literature. Web of Science or Scopus are recommended for policy, regulatory and labelling issues, but for Canadian content, try CPI.Q or Canadian Public Policy Online.