Potassium nitrate

Potassium nitrate is a chemical salt that occurs naturally in mineral deposits and is also found in plants. It is typically manufactured industrially through chemical synthesis, often involving the reaction of potassium hydroxide with nitric acid.

Potassium nitrate is primarily used as a preservative in cured meats, such as bacon and salami. It helps to inhibit the growth of bacteria, particularly Clostridium botulinum, and contributes to the characteristic pink colour and cured flavour of these products.

Potassium nitrate is an authorised food additive in the UK and EU, listed under E number E252. It has been evaluated by EFSA, which has established an acceptable daily intake (ADI) for nitrates and nitrites. While concerns exist regarding the potential formation of nitrosamines from nitrites in cured meats, the evidence linking moderate consumption of cured meats containing nitrates/nitrites to cancer in humans is mixed and subject to ongoing research. The UK government's dietary advice does not set specific limits for nitrate or nitrite intake from food additives.