Food grade sodium metabisulfite has an anti browning effect in food.

Browning reaction is the most common discoloration phenomenon in food processing, which can be divided into two categories based on its mechanism: enzymatic browning and non enzymatic browning.

Non enzymatic browning: Non enzymatic browning can be divided into the following three types

1. When reducing sugar and amino acid are heated together, they will form brown “melanoid”, which is called carbonyl ammonia reaction, also known as “Maillard reaction”. Non reducing sugars will not produce Maillard reaction without hydrolysis.

2. Sugar heated above its melting point in the absence of amino compounds will also produce dark brown pigment substances, which is called caramelization effect.

3. During storage, citrus juice darkens in color, emits carbon dioxide, and the content of ascorbic acid decreases. This is due to the browning caused by the active oxidation of ascorbic acid.

Sodium Metabisulfite Anti Browning

Enzymatic browning: Enzymatic browning is a reaction process that occurs in plant-based foods such as fruits and vegetables, where phenolic enzymes catalyze the formation of quinones and their polymers. After enzymatic browning occurs in fruits and vegetables, the color of the product darkens. To protect the original color of fruits and vegetables, a short-term blanching process that inactivates enzymes is often carried out under weak alkaline conditions, and then the intention of color protection is achieved. In addition to blanching, enzymatic browning can also be avoided and suppressed by controlling acidity, adding antioxidants (such as sodium isoascorbate), sulfite substances (such as sulfur dioxide, sodium metabisulfite) to inhibit enzyme activity, and blocking oxygen.