Red 2G

Red 2G

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Structure of Red 2G

Red 2G is a synthetic azo dye that was commonly used in the food industry to impart a red color to various products. It is known chemically as sodium 2-(2,5-dimethoxyphenylazo)-1-naphthol-4-sulfonate. The dye is part of the azo compound family, which is characterized by the presence of the functional group R-N=N-R', where R and R' can be either aryl or alkyl groups.

Chemical Properties

Red 2G is a water-soluble dye, which makes it suitable for use in a variety of aqueous food products. The chemical structure of Red 2G includes a naphthol group and a sulfonate group, which contribute to its solubility and color properties. The presence of the azo group is responsible for the vivid red color, as it allows for the absorption of light in the visible spectrum.

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3D space-filling model of Red 2G sodium

The molecular formula of Red 2G is C16H11N2NaO5S, and it has a molar mass of 372.32 g/mol. The dye is typically available as a sodium salt, which enhances its solubility in water.

Uses in Industry

Historically, Red 2G was used in the food industry to color products such as sausages, burgers, and other processed meats. Its ability to produce a stable and intense red hue made it a popular choice for manufacturers looking to enhance the visual appeal of their products.

Health and Safety Concerns

Concerns about the safety of Red 2G have led to its ban in many countries. The primary health concern associated with Red 2G is its potential to be metabolized into aniline, a compound that has been linked to carcinogenic effects in humans. As a result, regulatory bodies such as the European Food Safety Authority (EFSA) have prohibited its use in food products.

Synthesis

The synthesis of Red 2G involves the diazotization of 2,5-dimethoxyaniline followed by coupling with 1-naphthol-4-sulfonic acid. This process is typical of azo dye synthesis, where an aromatic amine is converted into a diazonium salt and then coupled with a phenolic compound.

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Synthesis of Acid Red 1, a related compound

Environmental Impact

The production and disposal of azo dyes like Red 2G can have significant environmental impacts. The dyes can contribute to water pollution if not properly managed, as they are often resistant to biodegradation. Efforts to develop more environmentally friendly dyes and improve waste treatment processes are ongoing in the industry.

Related Pages

• Azo compound
• Food coloring
• Carcinogen
• European Food Safety Authority