Why additives are used
Food additives are substances added in small amounts to food to keep it fresh longer, make it look and taste better, or improve its texture. They are classified by function. Governments set safety limits for each additive, and many carry an identifying code (an E-number) on the label. Used correctly in small, approved amounts they are considered safe.
Main types
- Preservatives slow the growth of bacteria and fungi, so food lasts longer. Examples: sodium benzoate, sodium nitrite, and everyday salt or sugar.
- Antioxidants stop food (especially oils) from being oxidised and turning rancid. Example: ascorbic acid (vitamin C).
- Flavourings and flavour enhancers improve taste; monosodium glutamate (MSG) is a common flavour enhancer.
- Colourings (dyes) make food attractive; they can be natural (such as carotene) or synthetic.
- Stabilisers and thickeners keep the texture smooth and stop ingredients separating.
- Sweeteners add sweetness; artificial ones such as aspartame and saccharin add almost no energy, useful for people avoiding sugar.
- Emulsifiers allow oil and water to mix evenly, as in mayonnaise and ice cream.
| Additive | Function |
|---|---|
| Sodium benzoate | Preservative |
| Ascorbic acid | Antioxidant |
| MSG | Flavour enhancer |
| Aspartame | Sweetener |
Key idea
Match the function: preservative → longer shelf life; antioxidant → prevents rancidity; enhancer → stronger taste; sweetener → sweetness with little energy.
Worked example
A bottle of cooking oil lists vitamin C on its label. What is its role? Vitamin C (ascorbic acid) is an antioxidant; it prevents the oil from oxidising and becoming rancid, keeping it fresh longer.
Remember
- Additives are used in small, controlled amounts.
- Excess or banned additives (such as too much nitrite) can harm health.
- Always link an additive to its function.