Tartrazine is a synthetic lemon yellow azo dye used as a food colouring agent. It is commonly added to a variety of food and beverage products to give them a yellow color. It is also used in cosmetics, medications, and other non-food products.
- Food sweetener refers to substances added to food to provide sweetness without significantly increasing the calorie content, such as sugar substitutes. Tartrazine is not used as a sweetener.
- Food fortifier is a substance added to food to enhance its nutritional value, such as vitamins or minerals. Tartrazine does not serve this purpose.
- Food preservative is used to prevent spoilage and extend the shelf life of food, which is not the role of tartrazine.
Thus, the correct answer is option (1): Tartrazine is a food colouring agent.