Sodium Bicarbonate

About This Product

Sodium bicarbonate, also known as sodium hydrogen carbonate or baking soda, is authorised as food additive E500(ii) in the EU and UK. Its CAS number is 144-55-8, its formula NaHCO3 and its molar mass 84.01 g/mol. Food grade is a white, odourless crystalline powder or granule with a slightly saline, alkaline taste, soluble in water to give a mildly alkaline solution.

Its main use is chemical leavening. When sodium bicarbonate meets an acid in a moist dough or batter it releases carbon dioxide, and heat alone also releases part of the gas. By weight about 52 % of sodium bicarbonate can be liberated as CO2 when fully reacted with acid. It is the base of baking powders and of self-raising flour, and is used in cakes, muffins, scones, soda bread, biscuits, crackers, pancakes and batters. Typical addition rates are around 0.5 % to 2 % of flour weight, depending on the product and on the acid it is paired with. It is also used in effervescent drinks and tablets, in honeycomb and other aerated confectionery, to adjust pH in cocoa, vegetable and beverage processing, and as a sodium and bicarbonate source in mineral waters and nutrition products.

Correct balancing with the leavening acid matters. The neutralising value of an acid is the weight of sodium bicarbonate neutralised by 100 parts of the acid; sodium acid pyrophosphate is typically around 72 and monocalcium phosphate around 80. Excess bicarbonate leaves a soapy, alkaline taste and yellowish crumb; too little leaves the product dense and sour. The acid also sets the timing of gas release, from fast in-mixer reaction to delayed release in the oven. Particle size affects reaction speed and distribution: fine powder reacts evenly in batters, while granular grades suit dry mixes and effervescent products.

Buyers typically agree the assay, loss on drying, pH of a 1 % solution, ammonium salts, insoluble matter, chloride, arsenic and lead, and the particle-size distribution. Some grades contain a small amount of flow agent, which must be declared, so state whether you need a pure grade. The grade should conform to the E500(ii) purity criteria in Regulation (EU) No 231/2012 and its GB equivalent, or FCC or JECFA for other markets.

Sodium carbonates are authorised in many food categories at quantum satis, but check Annex II of Regulation (EC) No 1333/2008 and the UK retained equivalent for your product, especially foods for infants. Declare it by function, for example raising agent: sodium bicarbonate, or raising agent: E500. It is about 27 % sodium, which counts towards the salt declaration; potassium bicarbonate, E501(ii), is an alternative for reduced-sodium recipes.

Sodium bicarbonate starts to decompose above about 50 °C and cakes with moisture, so store it sealed, cool and dry, away from acids. When you enquire, give the application, the particle size or grade, whether a flow agent is acceptable, the purity standard, pack size, annual volume and destination, and the documents you need.