Sunset Yellow FCF is a synthetic yellow azo dye with a pH dependent maximum absorption between 480 and 500 nm,p.463.Although there are reports it can induce an allergic reaction, this is not confirmed by scientific research. Sunset Yellow is useful in fermented foods which must be heat treated. It may be found in orange sodas, marzipan, Swiss rolls, apricot jam, citrus marmalade, lemon curd, sweets, beverage mix and packet soups, margarine, custard powders, packaged lemon gelatin desserts, energy drinks such as Lucozade, breadcrumbs, snack chips such as Doritos, packaged instant noodles, cheese sauce mixes and powdered marinades, bottled yellow and green food colouring, ice creams, pharmaceutical pills and prescription medicines, over-the-counter medicines cake decorations and icings, squashes, and other products with artificial yellow, orange or red colours.