E173 is a natural metal food additive approved by the European Union (EU). It is sometimes used as a colouring agent in food and drink products.
The common name for E173 is aluminium, i.e. the chemical element aluminium.
E173 is a silver / grey metal that tends to be used as a metallic surface coating. Aluminium is also used in many other food-related applications, such as for food-wrap foils, and even in part of water purification processes (incl. e.g. to assist in removing contaminants and other harmful micro-organisms from a raw water source.). To produce E173 commercially, bauxite is extracted and purified and electrolysis to take place in molten cryolite.
Although aluminium can form part of a healthy diet, large amounts or accumulations have been linked to skeletal deformations, Alzheimer's Disease (see also Alzheimers in the news), and osteoporosis (see also osteoporosis in the news). It is not yet clear whether or not aluminium accumulation in the brain is a cause or the result of Alzheimer's. Aluminium is generally considered harmful if inhaled or ingested on its own.
Examples of food and drink products that sometimes include E173:
- sugar-coated flour confectionery
- cake decorations