What are they used for?

Preservatives and antioxidants (E200–321)

These help manufacturers to keep food safe for longer.  Preservatives slow down the growth of harmful bacteria, while antioxidants prevent fat and oils from turning rancid and prevent discolouration.  Some antioxidants are used in processed foods to prevent colour and flavour additives from fading.

Emulsifiers, stabilisers and thickeners (E322–495)

Emulsifiers and stabilisers keep mixtures like oil and water from separating and make a creamier texture in foods including margarines and spreads, ice cream and peanut butter. These additives can also help manufacturers bulk out food with cheap ingredients such as water, air and processed starches.

Processing aids (E500–585)

These are substances used in food processing and include anti-caking agents that help foods to flow freely, gelling agents, firming agents, acids and release agents that prevent food from sticking to machinery and baking containers.

Flavour enhancers (E620–640)

These are used to enhance or modify the flavour of food. Monosodium glutamate (E621) is the best known. 

Glazing agents (E900–914)

These give a shiny appearance or polish to food, or provide a protective coat.

Flour treatments, improvers and bleaching agents (E920–928)

These are used in processed bread production.

Packing gases (E941–948)

These include inert gases such as nitrogen, used in ‘modified atmosphere’ packaging to keep food looking fresher for longer.

Sweeteners (E950–967)

These are substances other than sugar that produce a sweet taste, such as the artificial sweeteners saccharin and aspartame (NutraSweet), as well as 'bulk' sweeteners such as sorbitol and isomalt.

Flavours (no E numbers)

Flavourings make up about a fifth of all the additives we consume by weight and yet, unlike other additives, flavourings don't have to be tested for safety. Some flavourings may be 'natural', but many more are chemicals made in the laboratory. Flavourings can be used to disguise lack of real ingredients e.g. lemonade need contain no lemon, beef and tomato instant noodles no real beef or tomato.