(E524) Sodium Hydroxide 50%: Food Additive

E524 (Sodium Hydroxide) is an approved food additive used as an acidity regulator and pH-control agent in food production and processing.

E524 is the EU designation for sodium hydroxide, commonly known as caustic soda or lye. It is a strongly alkaline inorganic compound with the chemical formula NaOH. In the food industry, E524 is used as an acidity regulator to control and adjust the pH level of various food products to achieve the desired stability, flavor, and texture.

Origin and Production

Sodium hydroxide is produced industrially via the chloralkali process, in which a sodium chloride (salt) solution is electrolytically decomposed. The resulting sodium hydroxide is purified to different grades suitable for various applications, including food-grade production. For use in food manufacturing, only high-purity food-grade sodium hydroxide is permitted.

Function and Use in Food Products

E524 serves several important technological functions in food production:

• pH Regulation: Sodium hydroxide neutralizes acids in food products, raising the pH to improve product stability, safety, and taste.
• Pretzel and Lye Bread Production: Baked goods such as pretzels and lye rolls are dipped in a sodium hydroxide solution before baking, which creates their characteristic deep-brown, shiny crust and distinctive savory flavor.
• Olive Processing: E524 is used to reduce the natural bitterness of olives by breaking down the bitter glycoside oleuropein, making them palatable for consumption.
• Cocoa Processing (Dutch Process): Cocoa powder is treated with sodium hydroxide to alkalize it, which mellows the flavor, deepens the color, and improves its solubility in liquids.
• Noodle Production: In certain Asian noodle specialties such as ramen, sodium hydroxide treatment gives the noodles their characteristic firm texture and yellowish color.

Safety and Health Assessment

The use of E524 in food is evaluated and considered safe by the European Food Safety Authority (EFSA). In the finished food product, sodium hydroxide is no longer present in its original form, as it reacts with naturally occurring acids during processing and is neutralized. Only harmless sodium salts remain in the final product.

In concentrated form, sodium hydroxide is a highly caustic substance capable of causing severe burns to the skin, eyes, and mucous membranes. However, in food manufacturing it is used in controlled quantities and concentrations, ensuring that the finished product is completely safe for consumption.