The extraction method of Natural Pigment

As a kind of additive for food coloring, pigment has been widely used in the food, cosmetic, pharmaceutical and other industries. Natural edible pigment can be used not only as food coloring, some varieties due to the retention of a variety of natural active substances in plants, such as vitamin, amino acid, nucleotide, small molecule active skin, aromatic substances and some essential elements and so on. Therefore, it also has the both nutrition and health functions.
At present, the main extraction methods commonly used are as following:
1. Solvent extraction method: The commonly used solvent extraction methods are dipping, seepage flow, reflux and continuous reflux and so on. This method is often used for extraction of water soluble, alcohol soluble anthocyanin and flavonoid soluble pigments. According to the difference of pigment properties, select the different extraction solvents, and then through filter, vacuum concentrating, vacuum drying to obtain coarse pigment.
2. Press method: Using the extraction method to crushing the fresh leaves, fruit and peel of plants squeezed out with plant pigment composition in the slurry. This method is suitable for extraction of water soluble pigment, but the impurities in extraction of pigment is higher, need to be further refined.
3. Crushing method: After drying, pulverizing the plant samples, can made pigment products, such as cocoa pigment.
4. The enzyme reaction method: The enzyme reaction is through the enzyme reaction to produce the required color, such as the gardenia yellow pigment by enzyme treatment can produce gardenia blue pigment and red pigment.
5. Supercritical fluid extraction: Supercritical fluid extraction is a new extraction separation technology. Through the use of fluid in a region neat the critical point of the target substance in raw material has unique solubility and mass transfer rate and other characteristics, through the regulation of pressure and temperature, extraction and separation selectivity for the target substance. This technology is suitable for the extraction and separation of heat sensitive, non-volatile, fat soluble pigment, such as Paprika Oleoresin, Carotene, Annatto, Lutein and Lycopene and so on.
6. The ultrasonic extraction method: Sonic extraction method is using ultrasound to generate strong vibration, high acceleration, strong cavitation effect, mixing and other special effects to destroy the plant cells. The solvent penetration to extract cells, so as to be chemical constituents of extract dissolved in the liquid, and then purified to obtain the required components through chemical separation. The ultrasonic extraction method has been used in the extraction of Natural Edible Pigment, such as Chlorophyll, Curcumin, Gardenia Yellow pigment and so on.
7. Microwave extraction method: Microwave extraction method is the microwave activation combined with traditional solvent extraction to form a new extraction technology. The basic principle of it is to use the difference of microwave absorption ability in the microwave field, the extraction system in some regions or some components are selective heating, so that the target components leaching from the raw material of dissolution.