Para Red dye is an industrial azo dye intended for printing inks and textiles that was found illegally used as a food colourant, triggering a major product recall in 2005. The contamination was discovered in chilli powder and products containing it, including Worcester sauce and hundreds of ready meals, after testing revealed the unauthorised dye. Para Red is chemically related to Sudan dyes, a family of industrial colorants banned from food over genotoxic and carcinogenic concerns, and its presence suggested deliberate adulteration to enhance the colour of inferior spices. The incident prompted the largest food recall in UK history at the time, sweeping tests of spice supply chains, and lasting changes to import controls on chilli products. It remains a landmark case in food fraud, showing how adulteration at the raw-material stage can contaminate vast numbers of finished products.