Strawberry leaves green pigment
Physical and chemical properties
The main components are chlorophyll compounds.
Soluble in ethyl acetate, dark green;
Soluble in ethanol, acetone, pasty cream, and dark green;
Dissolved in milk, it is dark green;
Soluble in peanut oil, green;
Slightly soluble in acetic acid, it is dark green;
Insoluble in water and sodium carbonate solution.
When pH=1~9, it is bright green; when pH=1-14, it is light green; when pH is above 8, white precipitation is produced.
Excellent thermal stability under acidic conditions and very good light fastness.
Green colorant can be used for coloring food
The extraction method of green pigment in strawberry leaves
- Distilled water
- Copper acetate (zinc acetate)
- Ethyl acetate
- Ultrafiltration device
- Macroporous resin column
- Vacuum concentration device
Raw material → pretreatment → leaching (Solid-Liquid Extraction) → ultrafiltration → extraction → elution → concentration → pigment solution
Ingredients: Fresh strawberry leaves
Pretreatment: Wash and dry the leaves of strawberries, mash them
Extraction: Add the mixed solution of copper acetate and 75% ethanol or the mixed solution of zinc acetate and 75% ethanol to the crushed leaves for extraction. The amount of leaching solvent is appropriate to immerse the raw materials, soak at room temperature for 3omin, and filter to obtain the leaching solution
Ultrafiltration: The filtered extract is subjected to ultrafiltration to remove impurities such as small molecular sugars, organic acids, and pectin.
Extraction: The leaching solution after ultrafiltration to remove impurities is extracted with a macroporous resin column (AR8 cross-linked polystyrene resin is loaded into a glass tube)
Elution: First wash off impurities with water, then use ethyl acetate to elute the green pigment
Concentration: The eluent is concentrated under reduced pressure to obtain a concentrated pigment solution