Fluorescent light

Visible light produced by fluorescence, notably from a discharge tube whose inner phosphor coating is excited by ultraviolet from mercury vapour. This light can speed oxidative spoilage of foods like oils, nuts and milk in storage, so light-barrier packaging is used. Retail display lighting accelerates photo-oxidation: riboflavin-sensitised reactions in milk produce the ‘sunlight’ off-flavour within hours, and unsaturated oils develop rancidity. Mitigation combines UV-filtering tubes or LEDs, opaque or amber packaging, and antioxidant systems — lighting specifications now feature in shelf-life protocols.