Caramel pigment is a dark brown black liquid or solid with special sweetness and pleasant bitterness. Soluble in water, insoluble in common organic solvents and oils. The aqueous solution is reddish brown and transparent, without turbidity or precipitation. Stable to light and heat. It has colloidal properties and isoelectric point. Its pH value varies with the manufacturing method, and is usually 3~4.5.

As a colorant, the most important index of caramel pigment is color intensity (EBC unit). It is stipulated in China that EBC is in direct proportion to the light absorption value (W/V) of 0. 1% caramel solution measured by spectrophotometer at the wavelength of 6 10nm. The greater the absorption value (a), the darker the color. Although the color intensity of caramel pigment is important, its hue is also very important. Tone index is an important measure of hue and redness of caramel pigment. The factory is working hard to reduce the viscosity of caramel, thus expanding its application scope. Some caramel pigments have the same solid content and specific gravity as other caramel pigments, but they are used in baking industry because of their low viscosity, high fluidity, good stability and uniform coloring. Caramel for baking mainly requires good fluidity, easy mixing with flour, and does not require too high coloring rate, so the processing technology must be determined according to its use. Some data show that the color ratio of caramel increases with the extension of heating time, but high temperature is easy to polymerize macromolecules, increase viscosity and decrease fluidity.